Methods of producing functionalized powder particles

Abstract

To provide a filter configured to lyse a cell.SOLUTION: The filter comprises: a chamber containing a plurality of surface-etched powder particles, where each of the surface-etched powder particles independently comprises a crystalline, polycrystalline, semi-crystalline or amorphous semiconductor or insulator powder particle, where the etching is such that each of the surface-etched powder particles independently forms a structure selected from the group consisting of pores, pits, craters, nanowires, cones, pinnacles, hoodoos, coral, cords, walls, fins, ridges, crags, pyramids, and inverted pyramids; an inlet fluidically coupled to the chamber; and an outlet fluidically coupled to the chamber. When a composition comprising the cell is passed through the filter from the inlet to the outlet, one or more of the surface-etched powder particles contact the cell, thereby lysing the cell.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] Cross-reference This application claims the benefit of U.S. Provisional Patent Application No. 62 / 728,570, filed Sep. 7, 2018, which is incorporated herein by reference in its entirety.

Background Art

[0002] Silicon is the second most abundant element in the earth's crust and is commercially used in structures, steel refining, and the electronics industry. Pure silicon is an intrinsic semiconductor, but has too low a conductivity to be used in electronics without doping it with small concentrations of other elements to increase its conductivity. Specifically, single crystal allotropes of silicon are used to produce silicon wafers used in the semiconductor industry. Recent research has focused on the formation of nanowires on silicon wafers for application in photovoltaic devices and batteries. Methods for synthesizing silicon nanowires include laser beam ablation, ion beam etching, chemical vapor deposition, and vapor-liquid-solid growth, and current research has focused on the controlled formation of nanowires along specific directions.

Summary of the Invention

[0003] Conventional methods for fabricating nanowires often require expensive high-temperature and high-vacuum environments, which limits the size, scalability, and production throughput of the processed substrates. Further, conventional methods for fabricating nanowires typically require high-purity single-crystalline silicon wafers, which are costly to produce and have limited envisioned uses due to their flat, fixed shape. There is still a great need for methods of producing structures containing nanostructures such as nanowires on (e.g., crystalline, polycrystalline, semi-crystalline, amorphous) semiconductor powders, particles, or grains. The present disclosure addresses such needs and provides related advantages.

[0004] In certain aspects, the present disclosure provides a method of forming structures on (e.g., powder) particles (e.g., microparticles), the method comprising: (a) providing one or more (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) semiconductor or insulator powder particles; (b) optionally removing surface contaminants from one or more of the powder particles; (c) optionally removing oxides from one or more of the powder particles; (d) forming a first type of structure on one or more of the powder particles, thereby forming one or more homofunctional powder particles; and (e) optionally forming a second type of structure on one or more of the homofunctional powder particles, thereby forming one or more heterofunctional powder particles. In some embodiments, the first type and / or second type of structure is selected from the group consisting of, for example, optionally, pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, grooves, fins, ridges, cliffs, pyramids and inverted pyramids. In some embodiments, the powder particles (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) comprise powder particles comprising Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds composed of three or more elements. The powder particles may comprise one or more crystal grains, or the powder particles may consist of a single crystal grain.

[0005] When performing any of the subject methods, the method may include (b) a step of removing surface contaminants from one or more powder particles. In some embodiments, the method includes (c) a step of removing oxides from one or more powder particles. In some embodiments, the method is a step of forming a structure (e.g., of the second type) on one or more homofunctional powder particles, thereby forming one or more heterofunctional powder particles. The step of forming (d) may include a step of forming a structure (e.g., of the first type) on the surface of the powder particles or within the pores. The step of forming (e) may include a step of forming a structure (e.g., of the second type) on the surface of the powder particles or within the pores. At least one of the steps of forming (d) and (e) may include lithography. In some embodiments, each of the steps of forming (d) and (e) independently includes a process selected from the group consisting of metal-assisted chemical etching and chemical etching. At least one of the steps of forming (d) and (e) may include metal-assisted chemical etching, where metal-assisted chemical etching includes depositing metal ions on the surface of the powder particles and exposing the metal ions to an etching solution to etch the powder particles. The metal ions may be selected from noble metals and rare metals, for example, without limitation. In some embodiments, the etching solution is a plasma, a gas, or a solution. The etching solution may be a solution containing an etching solution and an oxidizing agent. The first type of structure may be a submillistructure such as a micro-structure or a nano-structure. In some embodiments, the second type of structure is a submillistructure such as a micro-structure or a nano-structure. The methods described herein may further include subjecting one or more functional powder particles to a process selected from the group consisting of film coating, plating, chemical functionalization, doping, nanoparticle decoration, lithography, and combinations thereof.The first type of structure and the second type of structure may be selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like portions, ridge-like portions, cliffs, pyramids, and inverse pyramids.

[0006] In some embodiments, the present disclosure provides a surface comprising one or more functional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles optionally include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like portions, ridge-like portions, cliffs, pyramids and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 microns. The (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) powder particles can be powder particles selected from the group consisting of elements of Group IVA, compounds of Groups IV-VI, compounds of Groups II-IVB, compounds of Groups I-VII, compounds of Groups II-VI, compounds of Groups III-V, compounds of Groups IV-IV, transition metal oxides, and compounds composed of three or more elements (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous elements or compounds). In some embodiments, the powder particles include one or more crystal grains such as single crystal grains. The diameter of the powder particles may be from 0.1 μm to 1,000 μm. In some embodiments, the powder particles include two or more structures selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like portions, ridge-like portions, cliffs, pyramids and inverse pyramids. The one or more structures may be submillistructures such as microstructures or nanostructures. In some embodiments, the average diameter of the smallest 30% of the powder particles is 200% smaller than the average diameter of the largest 10% of the powder particles. The surface described herein may further include a film that separates the powder particles from the atmosphere. The surface may be anti-reflective, reflective, absorptive, adsorptive, adhesive, refractive, abrasive, conductive, insulating, highly chemically reactive, chemically inert, luminescent, antibacterial, cytolytic, non-wetting, hydrophobic, hydrophilic, antifouling, anti-adhesive, anti-slip, antistatic, or a combination thereof.In some embodiments, the powder particles include one or more structures selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like portions, ridge-like portions, cliffs, pyramids, and inverse pyramids. In some aspects, the present disclosure provides a method of transferring or replicating a surface structure of a product, the method comprising using powder particles that are functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous semiconductors, or insulators) in one or more of the surfaces evaluated herein, such as molds or fungi.

[0007] In some embodiments, the present disclosure provides hetero-functional (e.g., crystalline, polycrystalline, or semi-crystalline semiconductor or insulator) powder particles, where the powder particles include two or more types of submillistructures. In some embodiments, the present disclosure provides functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator) powder particles, where the powder particles include submillistructures and further include a film coating, plating, chemical functionalization, dopant, nanoparticle decoration, or surface termination. In some embodiments, the present disclosure provides homo-functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator) powder particles, where the powder particles include a structure selected from the group consisting of pores, craters, cones, spires, pillars, corals, cords, walls, grooves, fins, ridges, cliffs, pyramids, and inverse pyramids. In some embodiments, the present disclosure provides homo-functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator) powder particles, where the powder particles include a structure selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, grooves, fins, ridges, cliffs, pyramids, and inverse pyramids, and where the powder particles are not elemental silicon particles. The diameter of the powder particles described herein may be from 0.01 μm to 10,000 μm. In some embodiments, the diameter of the particles is from 0.1 μm to 1,000 μm. The particles may be (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) powder particles of an element or compound selected from the group consisting of Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements. In some embodiments, the particles include one or more crystal grains. The particles may consist of a single crystal grain. The two or more types of submillistructures may be selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, grooves, fins, ridges, cliffs, pyramids, and inverse pyramids.In some embodiments, the two or more types of structures are selected from microstructures and nanostructures.

[0008] The particles described herein may reflect up to 10% of the total electromagnetic radiation having a wavelength between 10 nm and 1 mm (e.g., specularly and / or diffusely). In some embodiments, the particles may reflect up to 10% of the total electromagnetic radiation having a wavelength between 10 nm and 400 nm (e.g., specularly and / or diffusely). In some embodiments, the particles may reflect up to 10% of the total electromagnetic radiation having a wavelength between 300 nm and 1,000 nm (e.g., specularly and / or diffusely). In some embodiments, the particles may reflect up to 10% of the total electromagnetic radiation having a wavelength between 700 nm and 1 mm (e.g., specularly and / or diffusely). The particles may include two or more overlapping structures. The particles may have a regular or irregular shape. The particles described herein may further include a film coating, plating, chemical functionalization, dopant, nanoparticle decoration, or surface termination. In some embodiments, the particles exhibit antibacterial properties.

[0009] In some aspects, the present disclosure provides a method of rupturing a cell membrane, the method including contacting the cell with powder particles described herein (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator), wherein the powder particles physically or chemically interact with the cell, thereby rupturing the cell.

[0010] In some aspects, the present disclosure provides a method of modifying the properties of a product, the method including the step of incorporating one or more functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) (e.g., semiconductor or insulator) powder particles into the product, where the powder particles include one or more submillistructures, and the diameter of the powder particles is from 0.01 μm to 10,000 μm. The (e.g., crystalline, polycrystalline, semi-crystalline, amorphous) powder particles may be powder particles of an element or compound selected from the group consisting of Group IVA, Group IV-VI, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds composed of three or more elements. The powder particles may contain one or more crystallites. For example, the powder particles may consist of a single crystallite. The diameter of the powder particles may be from 0.1 to 1,000 μm. The powder particles may contain two or more structures selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like parts, ridge-like parts, cliffs, pyramids and inverted pyramids. In some embodiments, the one or more submillistructures are selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like parts, ridge-like parts, cliffs, pyramids and inverted pyramids. The one or more structures may be selected from microstructures and nanostructures. In some examples, the product is selected from the group consisting of medical devices, cooking utensils, fixtures, countertops, vehicles, ships and aircraft. The product may be selected from the group consisting of office consumables, office equipment, electronic devices, containers, kitchen utensils, cooking utensils, household items, fabrics, hardware, consumer products, vehicles and ships, filters, pumps, aquatic devices, surfaces, furniture, fixtures, devices, building materials, armaments, tools, solar cells, currency, medical appliances, medical devices, paper products, manufacturing devices, food processing devices and optical devices. In some embodiments, the product includes rubber, plastic, metal, glass, or ceramic.The modifying step may include one or more of the steps of reducing the absorbance of visible light of the product, enhancing the absorbance of visible light, reducing the reflectivity of light, enhancing antibacterial properties, enhancing mud-proof properties, enhancing hydrophobicity, enhancing hydrophilicity, enhancing electrical conductivity, enhancing electrical resistivity, enhancing photoluminescence, increasing surface energy, decreasing surface energy, increasing the friction coefficient, and decreasing the friction coefficient. The incorporating step may include the step of coating the product with powder particles or the step of embedding powder particles into the product. The method described herein may further include the step of exposing the product to a process selected from the group consisting of film coating, plating, chemical functionalization, doping, nanoparticle decoration, lithography, and combinations thereof.

[0011] In certain embodiments herein, a method of lysing a cell (or a population thereof) (e.g., physically and / or non-chemically) is provided, the method including the step of contacting the cell (or population thereof) with functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) powder particles, where the powder particles include one or more submillistructures (e.g., as described in any suitable embodiment herein), and the diameter of the powder particles is from 0.01 to 10,000 microns. In certain embodiments, the functional particles are formed on the surface of the product. In other certain embodiments, the functional particles are not loosely embedded in another material or surface in a powder-like form or the like. In some embodiments, all or part of the cells are physically lysed, where at least 30% of the cells are lysed (e.g., at least 50% of the cells are lysed). Any suitable particles provided herein are optionally utilized.

[0012] In certain embodiments herein, a low-reflection surface (e.g., of a product) is provided, the surface comprising one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous (e.g., semiconductor or insulator) powder particles (e.g., a surface comprising one or more of the particles configured on its surface and / or one or more of the particles embedded in its surface), where the powder particles optionally include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 microns. In certain embodiments, the reflectivity (e.g., of reflected light and / or scattered light) is less than about 25% (e.g., less than about 15%, less than about 10%, etc.) than other equivalent surfaces, and one or more of the powder particles are missing at a particular wavelength (e.g., one or more of the wavelengths of light described in the examples and drawings disclosed herein such as IR, visible wavelengths, and / or UV wavelengths). In further particular embodiments, the reflectivity of the surface (e.g., of reflected light and / or scattered light) is less than 5% (e.g., less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, less than 0.2%, etc.) at a particular wavelength (e.g., such as IR, visible wavelengths, and / or UV wavelengths). In certain embodiments, the surface is a material (e.g., bulk) in which the powder particles are incorporated in and / or into its material, and the material is silicon or silicon monoxide. In some embodiments, the powder particles are any of the particles of one of the preceding claims. Any suitable particles provided herein are optionally utilized.

[0013] In other embodiments herein, a method of modifying the light reflectivity of a product is provided, the method comprising incorporating one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles into the product (e.g., the surface and / or its bulk material), where the powder particles include one or more submillistructures, and the diameter of the powder particles is from 0.01 to 10,000 microns. In some embodiments, the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements. In certain embodiments, the one or more submillistructures are selected from pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverse pyramids. In some embodiments, the reflectivity (e.g., of reflected light and / or scattered light) is less than about 25% (e.g., less than about 15%, less than about 10%, etc.) than other equivalent surfaces and is lacking in one or more powder particles (e.g., at specific wavelengths such as IR, visible wavelengths, and / or UV wavelengths). In certain embodiments, the surface reflectivity (e.g., of reflected light and / or scattered light) is less than 5% (e.g., less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, less than 0.2%, etc.) (e.g., at specific wavelengths such as IR, visible wavelengths, and / or UV wavelengths). Any suitable particles provided herein may be optionally utilized.

[0014] In some embodiments herein, a color - fade - resistant dye (or a product containing such a dye incorporated into the product or its surface) is provided, the dye comprising functional crystalline, polycrystalline, semi - crystalline, amorphous (e.g., semiconductor or insulator) powder particles, where the powder particles include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 microns. In certain embodiments, the powder particles are any of the particles of one of the preceding claims. Any suitable particles provided herein are optionally utilized.

[0015] In certain embodiments, a method for forming a color - fade - resistant product herein is provided, the method comprising incorporating into the product (e.g., its surface or the bulk of the material) functional crystalline, polycrystalline, semi - crystalline, amorphous (e.g., semiconductor or insulator) powder particles that resist color fade from one or more light exposures, where the powder particles include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 microns. Any suitable particles provided herein are optionally utilized.

[0016] In some embodiments, provided herein are functional crystalline, polycrystalline, semi-crystalline, or amorphous (e.g., semiconductor or insulator) particles, the particles comprising one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fin-like portions, ridge-like portions, cliffs, pyramids and inverted pyramids, and the diameter of the powder particles being from 0.01 to 10,000 microns, and wherein at least a portion of the particle crystal lattice is altered relative to other equivalent particles not functionalized with one or more structures. In some embodiments, at least a portion of the particle crystal lattice is expanded and / or contracted with isotopes. In certain embodiments, at least a portion of the particle crystal lattice is anisotropically expanded and / or contracted. In some embodiments, the particle crystal lattice is anisotropically expanded and / or contracted by at least 0.1% along <111> and / or <311> crystallographic directions relative to other equivalent particles not functionalized with one or more structures. In certain embodiments, the band structure is altered for at least a portion of the particle relative to other equivalent particles not functionalized with one or more structures. Any suitable particles provided herein are optionally utilized.

[0017] In some embodiments herein, a method is provided for modifying the band structure of at least a portion of a particle, the process comprising providing (e.g., by the process of any one of the claims) on the surface of the particle one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverted pyramids, where the diameter of the powder particles is from 0.01 to 10,000 microns, and where at least a portion of the particle crystal lattice is expanded and / or contracted isotopically and / or anisotropically relative to other equivalent particles not functionalized with one or more structures. In certain embodiments, the particle crystal lattice is expanded and / or contracted anisotropically by at least 0.1% along the <111> and / or <311> crystallographic directions relative to other equivalent particles not functionalized with one or more structures. Any suitable particles provided herein are optionally utilized.

[0018] In some embodiments herein, a kit (e.g., for lysis of one or more cells within its chamber) is provided, the kit including a container and one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles, where the powder particles include (e.g., optionally) one or more structures selected from pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and where the diameter of the powder particles is from 0.01 to 10,000 microns, the container including a chamber, and the one or more functional particles being configured within the chamber. In certain embodiments, a container (e.g., for lysis of one or more cells within its chamber) is provided herein, the container including a chamber, the chamber including an inner surface or other functional surface, the container including one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles (embedded) within or on its inner surface, where the powder particles include (e.g., optionally) one or more structures selected from pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 μm. In some embodiments, the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements. In certain embodiments, the particles further include a film coating, chemical functionalization, dopant, nanoparticle decoration, or surface termination. In some embodiments, the functional particles are configured within the surface of the container. In certain embodiments, the functional particles are not loosely embedded in powder form or the like within another material or surface. In some embodiments, the functional particles mechanically bond, chemically bond, interact, or react with elements, compounds, molecules, and particles.In certain embodiments, the functional particles extract contaminants from a liquid or gas, a step of catalyzing or enhancing a chemical reaction, a step of lysing cells, a step of removing microorganisms from a liquid or gas, or any combination thereof.

[0019] In some embodiments, a bulk composite (e.g., of a product) is provided herein, the composite including powder particles of one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductors or insulators (e.g., a bulk including one or more of the particles configured below its surface), where the powder particles optionally include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverse pyramids, and the diameter of the powder particles is from 0.01 to 10,000 μm. In certain embodiments, the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds including three or more elements. In some embodiments, the powder particles include one or more crystallites. In certain embodiments, the powder particles consist of a single crystallite. In some embodiments, the diameter of the powder particles is from 0.1 to 1,000 μm. In certain embodiments, the powder particles include two or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, fins, ridges, cliffs, pyramids, and inverse pyramids. In some embodiments, one or more of the particle structures are submillistructures. In certain embodiments, one or more of the particle structures are selected from microstructures and nanostructures. In certain embodiments, the average diameter of the smallest 30% of the powder particles is 200% smaller than the average diameter of the largest 10% of the powder particles. In some embodiments, its surface is anti-reflective, reflective, adsorptive, conductive, insulating, anti-static, luminescent, antibacterial, non-wetting, hydrophobic, hydrophilic, anti-fouling, anti-adhesion, anti-slip, or any combination thereof.In certain embodiments, the bulk is antistatic, light-absorbing, light-reflective, antibacterial, conductive, insulating, electrically resistive, luminescent, or any combination thereof. In some embodiments, at least a portion of the bulk material is exposed and removed of a portion of at least one or more functional particles (e.g., or the functional particles in the bulk are otherwise exposed on or at the surface of the bulk material).

[0020] In certain embodiments, any submillistructure provided herein has dimensions less than 500 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 50 μm, etc., and for example, has dimensions of at least 1 nm, at least 2 nm, at least 5 nm, at least 25 nm, at least 50 nm, at least 100 nm, etc.

[0021] Incorporation by reference All publications, patents, and patent applications mentioned herein are hereby incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

Brief Description of the Drawings

[0022] The novel features of the invention are set forth with particularity in the appended claims. To better understand the features and advantages of the invention, reference should be made to the following detailed description, which illustrates exemplary embodiments in which the principles of the invention are utilized, and to the accompanying drawings.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

Figure 27

Figure 28

Figure 29

Figure 30

Figure 31

Figure 32

Figure 33

Figure 34

Figure 35

Figure 36

Figure 37

Figure 38

Mode for Carrying Out the Invention

[0023] Method for functionalizing particles In some embodiments, the present disclosure provides a method for forming a structure on powder particles. Figure 14 provides a schematic of an exemplary method for forming a structure on powder particles. In some embodiments, the method includes: (a) providing one or more (e.g., crystalline, polycrystalline, semi-crystalline, amorphous) (e.g., semiconductor or insulator) powder particles; (b) optionally removing surface contaminants from one or more of the powder particles; (c) optionally removing oxides from one or more of the powder particles; (d) forming a structure (e.g., a first type) on one or more of the powder particles, thereby forming one or more homo-functional powder particles; and (e) optionally forming a structure (e.g., a second type) on one or more of the homo-functional powder particles, thereby forming one or more hetero-functional powder particles, wherein the first and second type structures are selected from the group consisting of, for example, optionally pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, grooves, fin-like portions, ridge-like portions, cliffs, pyramids and inverse pyramids.

[0024] In some aspects, the present disclosure provides a method of forming a structure on powder particles, the method comprising providing one or more (e.g., crystalline, polycrystalline, semi-crystalline, amorphous) (e.g., semiconductor or insulator) powder particles, and forming a first type of structure on the one or more powder particles, thereby forming one or more homofunctional powder particles. The (e.g., first type of) structure may be selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, grooves, fins, ridges, cliffs, pyramids and inverse pyramids.

[0025] In some aspects, the present disclosure provides a method of forming a structure on powder particles, the method comprising: (a) providing one or more (e.g., crystalline, polycrystalline, semi-crystalline, amorphous) (e.g., semiconductor or insulator) powder particles; (b) removing surface contaminants from the one or more powder particles; (c) (optionally, for example) removing oxides from the one or more powder particles; (d) forming a (e.g., first type of) structure on the one or more powder particles, thereby forming one or more homofunctional powder particles; and (e) forming a (e.g., second type of) structure on the one or more homofunctional powder particles, thereby forming one or more heterofunctional powder particles, wherein the first type and / or second type of structure is (optionally, for example) selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids.

[0026] The powder processing method described herein is substantially different from typical methods used to functionalize wafers or other substrates. The increased surface area of the powder compared to other substrates can change reaction characteristics including the reaction rate of the functionalization reaction and the chemical and particle dynamics. In some examples, the chemical reactions used to create nanostructures on the surface of powder particles can increase the solution temperature due to exothermic reactions and rapid kinetics, which can change the reaction rate. In contrast, the same reaction on a wafer may result in negligible fluctuations in solution temperature due to the low surface area of the wafer. Exposed crystallographic faces or junctions can affect the functionalization process and the resulting morphology. In some examples, compared to wafers, the particle formation factors provide a greater number and diverse selection of exposed crystallographic faces or junctions. Stirring, or agitation, of the reaction solution can have different effects on the chemical reactions of powders and wafers, resulting in different functionalizations. In some examples, the powder moves in the solution, which can change the movement of catalytic nanoparticles within the powder particles and / or the dissolution of materials from the powder. Various morphologies may be formed due to differences in catalytic dynamics as a result of differences in movement between the powder particles and the wafer.

[0027] The methods described herein may be performed at room temperature and atmospheric pressure. In some embodiments, the pressure and temperature may be adjusted to change the structures and morphologies present on the surface of the powder particles. The reactions described herein may be performed in open or closed reaction vessels.

[0028] Powder particles The powder particles of the present disclosure may be crystalline, polycrystalline, semi-crystalline, or amorphous. Preferably, the powder particles are crystalline or amorphous. The particles are solid or may contain pores and may have regular or irregular shapes. The powder particles may be crystalline particles of an element or a mixture. Preferably, the particles are selected from the group consisting of elements of Group IVA, compounds of Groups IV-VI, compounds of Groups II-IVB, compounds of Groups I-VII, compounds of Groups II-VI, compounds of Groups III-V, compounds of Groups IV-IV, transition metal oxides, and compounds containing three or more elements. The powder particles may be composed of semiconductor or insulator elements or compounds, such as Si, Ge, Sn, CuCl, CaO, MgO, GaAs, GaN, BN, BP, AlN, InN, InP, SiO, and SiC.

[0029] The powder particles of the present disclosure may contain one or more crystallites. Optionally, the particles consist of a single crystallite. The powder particles may consist of two, three, or four or more crystallites held in intimate physical contact. The powder particles may have an irregular shape but have an average effective diameter based on the longest and shortest aspects of the particle. The average effective diameter of the particles may be from 0.1 μm to 10,000 μm, or from 0.01 μm to 10,000 μm such as from 0.1 μm to 1,000 μm. The average effective diameter of the particles may be at least about 0.01 μm, 0.1 μm, 1 μm, 10 μm, 100 μm, 1,000 μm, 10,000 μm or more. The average effective diameter of the particles may be about 10,000 μm, 1,000 μm, 100 μm, 10 μm, 1 μm, 0.1 μm, 0.01 μm or less. Optionally, the average effective diameter of the powder particles may be from 0.1 μm to 100 μm, from 0.1 μm to 10 μm, from 1 μm to 10,000 μm, from 1 μm to 1,000 μm, from 1 μm to 100 μm, from 10 μm to 10,000 μm, from 10 μm to 1,000 μm, or from 100 μm to 10,000 μm. The average effective diameter and the size distribution of the powder particles may be selected based on the desired properties and uses of the modified particles.

[0030] A group of powder particles may have a characteristic size distribution. The size distribution may be monomodal, bimodal, trimodal, or multimodal. The size distribution may be determined based on a characteristic size of the powder particles, such as an average diameter. The size distribution of the powder may be determined by sieving the powder particles. The size distribution of the powder particles may be defined such that about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 95% of the particles are within 50% of the average size of the particles. The size distribution of the particles may be defined such that at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 95% or more of the particles are within 50% of the average size of the particles. The size distribution of the particles may be defined such that about 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% or 10% or less of the particles are within 50% of the average size of the particles. The size distribution of a particular particle may be associated with a particular physical property of the functional powder material.

[0031] Pre-etching preparation Before forming a structure on the powder particles, it may be advantageous to remove surface contaminants from one or more powder particles. Surface contaminants may include any organic or inorganic gas, liquid or solid other than the desired material placed on the surface of the powder particles. The powder particles can be placed in a series of liquid baths or solutions having one or more solvents. Optionally, one or more powder particles are placed in a solvent bath, such as an acetone bath, for at least 10 minutes. The powder particles may further be placed in a second solvent bath, such as a methanol or ethanol bath, for at least 10 minutes. The step of removing surface contaminants from the powder particles may include ultrasonic treatment. In some embodiments, surface cleaning may be performed by immersing the powder in an acid bath or an acid bath enhanced with an oxidizing agent, which may be performed at room temperature or at an elevated temperature. Each of the chemical baths may include further continuous treatment. For example, a chemical bath with acetone or a chemical bath with ethanol may include agitation for at least 10 minutes followed by ultrasonic treatment for at least 10 minutes. In some embodiments, the powder particles may be placed in a solvent solution in which both agitation and ultrasonic treatment are simultaneously performed for at least 10 minutes to keep the powder in suspension. In some embodiments, surface contaminants may also be removed from one or more powder particles via long-term heating at a temperature of 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C or higher. The heating may occur in one or more various gas environments. In some embodiments, one or more powder particles may be heated in a vacuum at a pressure of 100 mbar or less. The powder particles are air, N 2 , CO 2 , He, H 2 , Ar or a mixture thereof.

[0032] The method of the present disclosure may also include the step of removing oxides from one or more powder particles. The one or more powder particles may be washed with an acidic solution or a basic solution. For example, the powder particles may be washed in a liquid bath containing a mixture of HF (>1M) and deionized H 2 O (DI-H 2 O) for at least 5 minutes. In some embodiments, the liquid bath may be buffered by adding NH 4 F to the HF solution. In some embodiments, the liquid bath may be illuminated to promote the dissolution of oxides and other surface atoms. The wavelength and intensity of the light may be varied depending on the chemical properties of the powder particles. The powder particles may be rinsed with a rinsing agent (e.g., DI-H 2 O) after the chemical bath. The immersed powder particles may be dried and flushed with a gas. The gas for flushing may contain N 2 , He, H 2 or another gas depending on the desired surface chemistry. The powder particles may be thermally annealed following the liquid bath preparation to reconstruct surface atoms and evaporate residual surface moisture. In some embodiments, the thermal annealing may be used instead of the above chemical bath method. The powder particles may be immersed in an ion-rich solution after the liquid bath treatment or thermal annealing. The ionic species are selected to change the surface chemistry depending on the desired use of the particles. In some embodiments, a complete rinse with a rinsing agent (e.g., DI-H 2 O) may be performed after the ion-rich solution liquid bath.

[0033] Etching method The methods described herein typically include a step of forming a first type of structure on one or more powder particles, thereby forming one or more homofunctional powder particles. In some embodiments, the method may further include a step of forming a second type of structure on one or more homofunctional powder particles, thereby forming one or more heterofunctional powder particles. The forming step may include forming the structure on the surface of the powder particles or within the pores. The forming method may be selected based on the desired bulk structure and powder surface morphology. Specific structural modifications may include single or multi-process etching by plasma, gas or solution methods. For example, the method of making functional powder particles may include a sequence of repeated metal-assisted chemical etching (MACE) followed by chemical etching (CE). Optionally, MACE may be performed several times consecutively without CE. Optionally, CE may be performed after which MACE is performed. The order of the various etching methods may be varied to create different forms of the surface structure. The powder particles may be rinsed with a rinsing agent (e.g., DI-H 2 O), flushed with a gas such as N 2 , He or H 2 after any etching method to remove any surface contaminants, and / or thermally annealed. Optionally, the particles may be rinsed with a solvent such as methanol, ethanol or acetone.

[0034] Metal-assisted chemical etching (MACE) typically involves two main steps: 1) depositing metal nanoparticles on the powder surface, and 2) etching in an acidic or basic bath. The two steps may optionally be carried out simultaneously in a single vessel. Optionally, the deposition and etching processes may be carried out separately. When separating, the deposition of metal nanoparticles may be carried out one or several times before etching. Etching may be carried out one or several times. Optionally, the solution may be stirred or agitated through the use of a magnetic stir bar, overhead stirrer, circulation pump, impeller, or other mixing or stirring device.

[0035] The deposition of metal nanoparticles on powder particles for the MACE process may occur in a solution containing an acid or base, DI-H 2 2O and metal ions such as (e.g., noble or rare metals) ions. For example, HF may be used at a concentration of at least 0.1 M. For example, one or more species of metal ions, including Ag, can be used. Noble metal salts such as AgNO 3 3 can be used to introduce metal ions into the bath. In some embodiments, but not limited to, Fe(NO 3 ) 3 3, Cu(NO 3 ) 2 2, H 2 2PtCl 6 6, K 2 2PtCl 6 6, HAuCl 4 4 or other metal salts containing RhCl 3 3 may be used instead of AgNO 3 3, or AgNO 3It may be used in coordination. Metal ions can be introduced into the bath solution by other methods including electrolysis. The temperature of the solution, duration, stirring and agitation speed, pH, chemical composition, amount, metal ion concentration, and concentration of base or acid can be adjusted to control the size and surface coverage of nanoparticle deposition. When two or more species of metal ions are deposited on the surface of the powder particles, they can be deposited simultaneously or in separate steps at the same or different surface concentrations. In some embodiments, the solution may be illuminated to vary the deposition behavior of the metal nanoparticles. The wavelength and intensity of the light may be varied depending on the physical and chemical properties of one or more of the powder particles. To vary the surface coverage of the metal nanoparticles, the powder particles may be thermally annealed after MACE.

[0036] Alternatively, MACE can be carried out in a solution containing an acid or base, oxidizing species and DI-H 2 O. In some embodiments, DI-H 2 O may be partially or completely replaced by another solvent such as methanol, ethanol, isopropyl alcohol or acetone. For example, HF can be preferably selected as the acid at a concentration exceeding 4M, and H 2 O 2 can be selected as the oxidizing agent. In some embodiments, HF may be replaced by another acid, such as H 3 PO 4 , HCl, or a base, such as NH 4 F. The oxidizing species are H 2 O 2 , O 2 gas, ozone, H 2 SO 4 , H 2 S 2 O 8 , NaClO, NaClO 4 , KMnO 4 and Fe(NO 3 ) 3may be selected from. Optionally, the reagent may be added to the solution over a period of time. The concentration of acid or base, oxidizing agent concentration, dissolution duration, stirring and agitation speed, pH, chemical composition, amount, rate of chemical addition, and temperature may be varied to control the structure and morphology of the etching performed on the powder particle surface. In some embodiments, the solution may be illuminated to vary the dissolution of the particles. The wavelength and intensity of the light may be varied depending on the physical and chemical properties of one or more powder particles, and the desired surface structures and morphologies. Excess metal nanoparticles may be removed from the powder particle surface. For example, HNO 3 and DI-H 2 O solution can be used to remove metal from the particle surface. In some embodiments, the metal may be removed from the particle surface using an acidic solution, such as sulfuric acid, perchloric acid, aqua regia. In some embodiments, the removal of metal nanoparticles can be achieved using electrochemical methods, suitable chemical methods, or a combination of both methods. In some embodiments, the recovered metal nanoparticles may be recovered and reused for further use.

[0037] When implementing a method of any subject matter, chemical etching (CE) of one or more powder particles may interfere with metal-assisted chemical etching and may be performed before or after it. CE typically includes any method for selectively removing surface material using means that are inherently chemical and not mechanical. The CE process may be performed one or more times in the method of the subject matter. The CE method may include an acid solution or a base solution having the treated powder particles. For example, the CE tank may contain KOH and DI-H 2 O. In some embodiments, KOH is NH 4 F, HF, NaOH, LiOH, RbOH, CsOH, NH 4 OH, Sr(OH) 2 、Ca(OH) 2 、Ba(OH) 2It may be substituted with acid species or base species such as tetramethylammonium hydroxide or HBr. Chemical concentration, solution temperature, duration, stirring and agitation speed, pH, chemical composition, amount, and rate of chemical addition may be varied according to the desired surface structure and morphology. In some embodiments, the solution may be illuminated to enhance the surface dissolution of the powder particles. The wavelength and intensity of the light may be varied according to the physical and chemical properties of one or more powder particles.

[0038] Additional processing After the formation of one or more structures on the powder particles, the resulting homo- or hetero-powder particles can be subjected to one or more additional processes. Any combination of the optional additional processes described below can be carried out in any order and repeated any number of times. In some examples, any additional process is carried out before incorporating the functional powder particles into the product. Alternatively, any additional treatment can be carried out after incorporating the functional powder particles into the product.

[0039] The additional processing methods include methods of film coating or plating one or more powder particles. Film coating or plating can include any process that results in the deposition of a thin film of material that covers the entire surface or a portion of the surface of the powder particles, which can be identical, semi-identical, non-identical, or patterned. For example, vapor deposition can be used to deposit a thin film. In some embodiments, chemical bath, electrochemical methods, spin coating, dip coating, spraying, open roll coating, or lithography methods can be used.

[0040] The additional treatment includes a method of chemically functionalizing the surface of one or more powder particles. Chemical functionalization can include any process that creates a reactive or non-reactive field on the surface of one or more powder particles. For example, the surface of the powder particles can be bonded to an active antibacterial chemical such as chlorhexidine digluconate or (3-aminopropyl)triethoxysilane. Alternatively, the surface of the particles can be functionalized through reaction with, for example, a silane compound, including but not limited to functionalizing compounds such as octadecyltrichlorosilane or 1H,1H,2H,2H-perfluorodecyltriethoxysilane, to produce a highly hydrophobic surface that can also improve the binding of the particles to a substrate. In some embodiments, the surface can be functionalized with a dispersant or a peptide. In some embodiments, the surface of the particles can be functionalized to assist the particles in binding or adhering to a product or a medium. For example, diethoxydiphenylsilane, allyltrichlorosilane, triethoxy-p-tolylsilane, allyltriethoxysilane, vinyltrimethoxysilane, or other derivatized silanes can be used to bind the particles in a polymer medium through covalent or non-covalent interactions. The powder particle surface can be functionalized with more than one chemical species depending on the desired material properties for the selected application. Chemical functionalization can include methods for changing properties such as surface energy, surface area, surface roughness, density profile, reflectivity, optical constants, charge, band gap, shear modulus, plasticity, specific weight, coefficient of friction, acoustic properties, thermal properties, optical properties, electrical properties, chemical properties, non-covalent interactions, photoluminescence, light absorption, hydrophobicity, and hydrophilicity.

[0041] Other additional processes may include a method of doping one or more powder particles via neutron irradiation. Exposure of the powder particles to neutron radiation can change their electronic properties, band structure, or their band gap. Sub-millimeter structures created via methods such as MACE may be sensitive to the doping of semiconductor particles. In some examples, nanostructure formation prior to neutron irradiation allows for specific structures and morphologies enhanced with desirable electronic properties.

[0042] As shown in FIGS. 12, 13, and 15, another additional process may include the decoration of one or more powder particles with nanoparticles. The nanoparticles can be deposited or dispersed on the surface of the functional powder particles by any method of nanoparticle synthesis. For example, the nanoparticles can be deposited in a chemical bath. In some embodiments, the nanoparticles can be deposited by vapor deposition. Nanoparticle decoration can be used to change and enhance the physical or chemical properties of the powder particles. The nanoparticles can be used to enhance the antibacterial properties of the powder particles. For example, Ag, Cu, or ZnO nanoparticles can be added to one or more powder particles for their antibacterial activity. Nanoparticles such as Ag, Au, and Cu can enhance the electrical and optical properties of the powder particles. The nanoparticles can decorate the powder particle surface to enhance UV light absorption. For example, Al 2 O 3 or ZnO can enhance the UV light absorption characteristics of the powder particles. The nanoparticles can also be utilized to protect the nanostructures from UV photodegradation. For example, CeO 2 nanoparticles can be used as a UV protectant.

[0043] structure The present disclosure provides powder particles comprising a structure, a method of forming these structures, and a composition comprising the powder particles. Any structure disclosed herein may refer to a submillimeter structure, such as a micro-structure or a nano-structure. Specific examples of suitable types of structures in the method and composition include, but are not limited to, pores, depressions, craters, nanowires, cones, spires, rock pillars, corals, cords, walls, fin-like parts, ridge-like parts, cliffs, pyramids, and inverted pyramids. Examples of nanostructures that can decorate functional powder particles are shown in FIG. 1.

[0044] Depressions, craters, and pores refer to indentations on the powder particles. Depressions and craters may have a depth-to-diameter ratio of less than 2. The term pore is used to refer to any indentation having a depth-to-diameter ratio of 2 or more. Pores, although not essential, may have two open ends. Depressions, craters, and pores may have openings of geometric or organic shapes. Exemplary images of depressions and pores on the particle surface are shown in FIGS. 2, 3, and 19.

[0045] The terms nanowire, spire, and pillar are used interchangeably and refer to an elongated structure extending outward from the powder particle. A nanowire or pillar may have a height-to-diameter ratio of 2, 3, 4, 5, 6, 7, 8, 9, 10, or more. A nanowire or pillar, although not essential, may have a circular cross-section. A nanowire or pillar may have a similar average cross-sectional area, or a variable cross-sectional area. Examples of nanowires and nanopillars on the surface of the powder particles are shown in FIG. 4. The term cone refers to a pillar structure whose cross-sectional area continuously decreases from the base to the tip.

[0046] The term pyramid refers to any structure extending outward from a powder particle whose cross-sectional area decreases from the base to the tip and has three or more sides. The pyramid structure, although not essential, may have acute or flat sides. The pyramid structure, although not essential, may have a truncated tip, or a flat tip. Examples of pyramid structures on the surface of the powder particles are shown in FIGS. 21 and 22.

[0047] The reverse pyramid refers to any concave pyramid structure that extends from the base to the tip, has a decreasing cross-sectional area, and has three or more sides. The reverse pyramid structure may, but is not required to, have flat sides, sharp corners, or a truncated or flat tip. An example of a reverse pyramid structure on the surface of a powder particle is shown in FIG. 20.

[0048] The term ridge or cliff refers to a protruding structure that intersects along its length and has a cross-sectional width at FWHM (full width at half maximum) that is submicron and smaller than its length. The ridge or cliff may consist of sections that are curved or straight along its length. The ridge or cliff may, but is not required to, form an enclosed, recessed area. Examples of ridges and cliffs on the surface of a powder particle are shown in FIG. 23.

[0049] The term wall refers to a protruding structure whose length is greater than its height or cross-sectional width and consists of a similar width-to-height ratio along its length. The wall may, but is not required to, have a constant cross-sectional width from the base to the top. An example of a wall on the surface of a powder particle is shown in FIG. 24(b).

[0050] The term fin refers to a protruding structure whose length is greater than its height or cross-sectional width and consists of a height that varies along its length. The fin may, but is not required to, have a decreasing cross-sectional area from the base to the top. An example of a fin on the surface of a powder particle is shown in FIG. 24(a).

[0051] The term cord refers to an elongated convex structure whose height does not exceed the width of the base. The cord may, but is not required to, have a semi-circular cross-sectional shape. The cord may, but is not required to, be parallel to other cords. An example of a cord on the surface of a powder particle is shown in FIG. 35.

[0052] The term "rock pillar" refers to a protruding pillar-like structure with a variable cross-sectional area or a variable cross-sectional shape that is interconnected or interconnected laterally. Figures 5, 33(c), and 33(d) depict several laterally interconnected nanopillars that can be classified as rock pillars.

[0053] The term "coral" refers to any elongated structure with an irregular morphology or a non-geometric shape. For example, an elongated structure whose direction changes along its length and whose cross-sectional area or cross-sectional shape is variable may be called coral. Corals may have interconnected or interconnected features, although this is not essential. Any nanostructure or microstructure that cannot be easily classified into other classes of structures may be considered to be coral. Figures 16, 17, 33(a), and 33(b) depict irregularly formed nanostructures that can be classified as corals.

[0054] A single powder particle can contain two or more types of structures. In some embodiments, as shown in Figure 6, the structures are layered on top of each other. For example, the powder particle can contain nanowires on the side of a pyramid. The nanowires can adorn the sides of pyramids, inverted pyramids, craters, cones, rock pillars, corals, cords, walls, fin-like parts, ridge-like things, cliffs, or other nanowires. Depressions and pores can adorn the surfaces of nanowires, craters, cones, pyramids, inverted pyramids, corals, cords, walls, fin-like parts, ridge-like things, cliffs, or rock pillars, or other depressions and pores. A single powder particle can contain any combination of first and second structures. For example, Figure 18 depicts a particle having a hetero-functional form that includes a pyramid structure and a coral structure. For example, Figure 2 depicts a particle having a repeating structure that includes depressions and pores. For example, Figure 36 depicts a particle having a hetero-functional form that includes cords and triangular opening-like depressions.

[0055] Structures formed on powder particles, including first and second structures, can be characterized by characteristic dimensions. Characteristic dimensions can include properties such as length, width, height, diameter, and circumference. The characteristic dimensions of structures formed on powder particles may be constant or may vary across the body of the structure. For example, a pyramid structure or a cone structure can be characterized as having a circumference that decreases from the base of the pyramid to the tip. Structures formed on powder particles can also have multiple characteristic dimensions, such as length and radius. A particular characteristic dimension, or range of characteristic dimensions, may be related to a certain physical property of the functional powder material. The characteristic dimensions of a particular structure can vary on a single particle or between particles.

[0056] Structures formed in the shape of powder particles can have characteristic dimensions of about 1 nm, 10 nm, 25 nm, 50 nm, 75 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 10 μm, 100 μm, or 1000 μm. Structures formed in the shape of powder particles can have characteristic dimensions of at least about 1 nm, 10 nm, 25 nm, 50 nm, 75 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 10 μm, 100 μm, or 1000 μm, or more. Structures formed in the shape of powder particles can have characteristic dimensions of about 1000 μm, 100 μm, 10 μm, 1 μm, 900 nm, 800 nm, 700 nm, 600 nm, 500 nm, 400 nm, 300 nm, 200 nm, 100 nm, 75 nm, 50 nm, 25 nm, 10 nm, 1 nm, or less.

[0057] Two characteristic dimensions of the structure formed on the powder particle may have a specific aspect ratio. For example, the aspect ratio may include the ratio of length to width for a particular structure. The aspect ratio may be calculated based on the average value of the characteristic dimensions. For example, a structure having a variable diameter may have an aspect ratio based on the average diameter over the length of the structure. A specific characteristic aspect ratio, or a range of aspect ratios, may be related to a certain physical property of the functional powder material. The aspect ratio of a particular structure may vary on a single powder particle or between two different powder particles.

[0058] In some cases, the structure formed on the powder particle may be characterized by more than one characteristic or trait dimension. The characteristic or trait dimensions may include width, height, depth, spacing, diameter, tip diameter, aperture width, tip-to-tip distance, base diameter, and peak width. In some cases, the characteristic or trait dimensions may have characteristic values or ranges. The range may be defined by the minimum and / or maximum dimensions of the structure dimensions. Table I below shows some approximate characteristic dimensions for various structures of the present invention. The actually observed characteristic dimensions may exceed or be below the mentioned characteristic dimension ranges by about 5%, 10%, 15%, 20%, 25%, or more.

[0059]

Table 1

[0060] Structures or groups of structures on the functional powder particles can be characterized as having an average aspect ratio of about 1:1000, 1:100, 1:10, 1:5, 1:2, 1:1, 2:1, 5:1, 10:1, 100:1, or about 1000:1. Structures or groups of structures on the functional powder particles can be characterized as having at least an average aspect ratio of about 1:1000, 1:100, 1:10, 1:5, 1:2, 1:1, 2:1, 5:1, 10:1, 100:1, or about 1000:1. Structures or groups of structures on the functional powder particles can be characterized as having an average aspect ratio not exceeding or less than about 1:1000, 1:100, 1:10, 1:5, 1:2, 1:1, 2:1, 5:1, 10:1, 100:1, or about 1000:1.

[0061] Structures on the powder particles can have a characteristic size distribution. The size distribution can be monomodal, bimodal, trimodal, or multimodal. The size distribution can be determined for any characteristic dimension of the structure. For example, functional powder particles functionalized with pillars can have a monomodal pillar length distribution around the average value of the pillar length. The size distribution of the structure can be determined such that about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% of the structures are within 50% of the average size of the structure. The size distribution of the structure can be determined such that at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95%, or more, of the structures are within 50% of the average size of the structure. The size distribution of the structure can be determined such that about 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, or 10% or less of the structures are within 50% of the average size of the structure. A particular characteristic structure size distribution may be related to a certain physical property of the functional powder particles. The size distribution of a particular structure can vary between regions of a single powder particle or between two different powder particles.

[0062] The structures on the particles can have a characteristic surface density. The surface density can be defined as the number of unique structures per unit area. The surface density can be calculated for each single type of structure (e.g., pillars), or can include the density of two or more types of structures (e.g., the total surface density of all structures on the powder particles). A particular characteristic surface density may be related to certain physical properties of the functional powder particles. The surface density of a particular structure can vary between regions of a single powder particle, or between two different powder particles.

[0063] The powder particles are at least about μm 2 1 structure per μm 2 5 structures per μm 2 10 structures per μm 2 15 structures per μm 2 20 structures per μm 2 25 structures per μm 2 30 structures per μm 2 40 structures per μm 2 50 structures per μm 2 100 structures per μm 2 250 structures per μm 2 500 structures per μm 2 1000 structures per μm, or 2 can have a structure surface density of 10,000 or more structures per μm. The powder particles are μm 2 about 10,000 structures per μm 2 1000 structures per μm 2 500 structures per μm 2 250 structures per μm 2 100 structures per μm 2 50 structures per μm 2 40 structures per μm 2 30 structures per μm 2 25 structures per μm 2 20 structures per μm 2 15 structures per μm 2 10 structures per μm 2 5 structures per μm 2It may have a per-structure or a structure surface density not exceeding less than one.

[0064] Functional particles In some embodiments, the present disclosure provides homofunctional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles include one type of structure selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids. In some embodiments, the present disclosure provides homofunctional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles include a structure selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids. In some embodiments, the present disclosure provides homofunctional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor) powder particles, where the powder particles include one type of structure selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids, and where the powder particles are not elemental silicon particles. In some embodiments, the present disclosure provides functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles include submillimeter structures and further include a film coating, plating, chemical functionalization, dopant, nanoparticle decoration or surface termination. In other embodiments, the present disclosure provides heterofunctional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles include two or more types of structures. The two or more types of structures may be selected from the group consisting of pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fins, ridges, cliffs, pyramids and inverse pyramids.

[0065] The average effective diameter of the functional powder particles is from 0.01 to 10,000 μm, for example, it may be from 0.1 to 10,000 μm, or from 0.1 to 1,000 μm. Optionally, the average effective diameter of the powder particles may be from 0.1 to 100 μm, from 0.1 to 10 μm, from 1 to 10,000 μm, from 1 to 1,000 μm, from 1 to 100 μm, from 10 to 10,000 μm, from 10 to 1,000 μm, or from 100 to 10,000 μm.

[0066] The functional powder particles may include two or more overlapping structures, such as nanowires on the side of a pyramid. In some embodiments, the nanowires may decorate the sides of a pyramid, an inverted pyramid, a cone, a rock pillar, a coral, a cord, a wall, a fin-like part, a ridged one, a cliff, or other nanowires, and the depressions and pores may decorate the surfaces of the nanowires, cones, pyramids, inverted pyramids, corals, cords, walls, fin-like parts, or rock pillars, or the depressions and pores. A single powder particle may include any combination of the first and second structures.

[0067] In some examples, the particles reflect up to an average of 0.1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 10 nm and 1,050 nm. In some embodiments, the particles may reflect up to an average of 0.01% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 10 nm and 400 nm, up to an average of 0.1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 300 nm and 1,050 nm, or up to an average of 0.1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 700 nm and 1,050 nm. In some examples, as seen in FIG. 37, the particles reflect up to an average of 0.03% of the total electromagnetic radiation at an incident angle of 45° between wavelengths of 190 nm and 900 nm. In some examples, the particles reflect up to an average of 0.046% of the total electromagnetic radiation at an incident angle of 45° between wavelengths of 180 nm and 380 nm and up to an average of 0.026% of the total electromagnetic radiation at an incident angle of 45° between wavelengths of 380 nm and 740 nm. In some examples, the particles reflect up to 1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 300 nm and 1,050 nm. In some embodiments, the particles may reflect up to 1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 10 nm and 400 nm, up to 1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 300 nm and 1,050 nm, or up to 1% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 700 nm and 1,050 nm. In some examples, the particles reflect up to an average of 10% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 10 nm and 1,050 nm. In some embodiments, the particles may reflect up to 10% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 10 nm and 400 nm, up to 10% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 190 nm and 900 nm, or up to 10% of the total electromagnetic radiation (e.g., specular and / or scattered) having a wavelength between 700 nm and 1,050 nm.In some examples, the particles reflect up to 25% of the total electromagnetic radiation (e.g., specular and / or scattered) having wavelengths between 300 nm and 1,050 nm. In some embodiments, the particles can reflect up to 25% of the total electromagnetic radiation (e.g., specular and / or scattered) between 10 nm and 400 nm, up to 25% of the total electromagnetic radiation (e.g., specular and / or scattered) between 190 nm and 900 nm, or up to 25% of the total electromagnetic radiation (e.g., specular and / or scattered) between 700 nm and 1,050 nm.

[0068] Physical and Chemical Properties of Functional Particles The structure and texture of the functional powder particles can change at least some of the physical and / or chemical properties of the particles. The properties can change radially and / or angularly. Examples of properties and characteristics of the powder particles that can be changed by the structure and texture include, but are not limited to, surface energy, surface area, surface roughness, density profile, refractive index, optical constants, electrostatics, band structure, band gap, shear modulus, plasticity, coefficient of friction, specific weight, acoustic properties, thermal properties, optical properties, electrical properties, chemical properties, non-covalent interactions, photoluminescence, light absorption, cell lysis, omniphobicity, hydrophobicity, and hydrophilicity.

[0069] Functional powder particles can exhibit altered material properties more readily than a generally functionalized substrate that is similarly structurally functionalized. Structurally functionalized powder particles will be more complex than similar structures on a non-particle substrate such as a Si wafer. Functional powder particles have a high surface area to volume ratio (or surface area to mass ratio) and are smaller than non-powder particle forms, so that more of the mass or volume of the functional powder particles is composed of sub-millimeter structures. Sub-millimeter structures (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) on the powder particles can exhibit a wider range of orientations than structures on a non-particle substrate due to functionalization across the entire powder surface. Omnidirectional structures can enhance the properties of functional powder particles for three-dimensional applications. Functional powder particles are characterized by a wider range of physical length scales than on a non-particle substrate. The wider range of length scales can provide a wider range of material properties in functional powder particles.

[0070] Functional (e.g., crystalline, polycrystalline, and semi-crystalline) powder particles can have a changed crystal lattice structure and band structure from non-functional particles or non-functional substrates. For example, FIG. 25 shows X-ray (Cu Kα 1 ) powder diffraction data from non-functional crystalline Si powder and functional crystalline Si powder prepared via the method described in Example 7 after 90 minutes of etching. These functional particles (average diameter of 45 μm) have a structurally functionalized surface that is 1.5 μm thick. This structural functionalization results in expansion and contraction of the lattice of the entire functional particle, including a hard core and a functionalized surface, even if the structural functionalization is in a very small amount of the particle volume. Expansion and contraction of the crystal lattice along the <111> and <311> directions are evident by the shift in the peak position of the Si(111) and Si(311) peaks, respectively. The change in the crystal lattice structure can potentially change the band structure compared to non-functional particles or non-functional substrates, and this change occurs without changing the bulk chemical composition or introducing bulk crystal defects.

[0071] Functional powder particles can change thermal properties. Thermal expansion and contraction can reduce the impact on nanostructures. Cracks and other mechanical failures can be reduced in functional powder particles.

[0072] Multiple functional particles Functional particles can form part of a homogenous mixture of similar particles or part of a heterogenous mixture of two or more different-shaped particles. One different shape may differ from the others in at least one physical or chemical property such as chemical composition, size, shape, surface variation, type of structure on the surface, type of subsurface structure, chemical functionalization, nanoparticle decoration, surface termination, or doping.

[0073] In some embodiments, two or more different-shaped functional particles are mixed together to achieve desired physical properties. For example, a mixture of functional particles containing different elemental or compound species such as Si or Ge can be used to provide a mixture with preferred optical properties. The packing density of the particles can be increased by mixing functional particles having different sizes, such that the smaller particles occupy or fill the voids between the larger particles. A mass density gradient can be formed by mixing particles of different sizes. A stepwise optical index of the refractive index can also be formed by mixing particles of different sizes. A mixture of particles can be formed in which there are particles with durable qualities and particles with delicate qualities. For example, large particles having an inverted pyramid structure can be mixed with small particles covered with nanowires. The small particles may occupy the voids between the larger particles such that the more delicate nanowires are protected from mechanical or other damage.

[0074] Those mixtures, either homogeneous or heterogeneous, can be used in various applications. By way of example, filters such as fluid filters or gas filters are mentioned, including containers containing one or more functional particles. In this example, the functional particles can mechanically or chemically bind, interact, or react with elements, compounds, molecules, particles, or cells as a fluid or gas flow through the filter. Applications of such filters include extraction of contaminants from fluids or gases, catalysis or enhancement of specific chemical reactions, lysis of cells for intracellular analysis and collection of cell components, and removal of unwanted microorganisms from fluids. This high surface area of the functional particles allows a greater amount of chemicals to be embedded or decorated per particle compared to non-functional particles. In some embodiments, the functional powder particles can be utilized in analytical columns. In some embodiments, the functional powder particles can be modified with functional groups such as flavor or aroma compounds. In some embodiments, nanoparticles containing flavor or aroma compounds can be embedded or decorated on the surface of the functional powder particles. The functional powder particles can move nanostructures or create replicas on other materials. For example, powder particles with nanowires can be used as molds, stamps, or templates to create structures on the surface of softer materials.

[0075] Composite of functional particles In some embodiments, the present disclosure provides a surface comprising one or more functional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor or insulator) powder particles, where the powder particles optionally include one or more structures selected from pores, depressions, craters, nanowires, cones, spires, rock pillars, corals, cords, walls, fin-like portions, ridged portions, cliffs, pyramids and inverted pyramids, and the diameter of the powder particles is from 0.01 μm to 10,000 μm. The average diameter of the smallest 30% of the powder particles may be 200% smaller than the average diameter of the largest 10% of the powder particles. Optionally, the average diameter of the smallest 10% of the powder particles may be 200% smaller than the average diameter of the largest 10% of the powder particles, the average diameter of the smallest 1% of the powder particles may be 200% smaller than the average diameter of the largest 10% of the powder particles, the average diameter of the smallest 30% of the powder particles may be 100% smaller than the average diameter of the largest 10% of the powder particles, or the average diameter of the smallest 10% of the powder particles may be 50% smaller than the average diameter of the largest 10% of the powder particles. The surface described herein may further include a film that separates the powder particles from the atmosphere. The surface may be anti-reflective, reflective, antibacterial, hydrophobic, hydrophilic, antifouling, non-stick, or may have physical properties or combinations of physical properties desirable for a selected application.

[0076] One or more of the functional particles described herein can be used, for example, as components or additives in bulk materials, fibers, surfaces, or surface coatings, as shown in FIG. 9. The concentration, distribution (e.g., out-of-plane and in-plane position) and orientation of the functional particles can be determined separately for a given application. The functional powder particles can change the interaction with the substrate or medium because they have an increased surface area compared to non-functional particles. For example, the functional powder particles can have an increased number of chemical or bonding sites compared to non-functional particles. The functional powder particles can be used to formulate more durable composites. The smaller length scale of the nanostructures can inhibit crack propagation compared to a substrate material such as a semiconductor wafer. In some examples, a decrease in the density of the functional particles can reduce the mass of the composite compared to non-functional particles.

[0077] In some examples, one or more functional particles are embedded in the surface such that at least one powder particle is exposed to the atmosphere. In this arrangement, the structure of the embedded functional particles is at least partially exposed on the surface of the matrix, medium, fiber, binder, or adhesive. Optionally, one or more functional particles can adhere to the matrix, medium, binder, or adhesive such that the particles are fully exposed. The height of the exposed particles can be varied, and the heights of the particles relative to each other can be uniform or non-uniform. Also, the volume of the exposed particles can be varied, and the volumes of the particles relative to each other can be uniform or non-uniform. Optionally, one or more functional particles can adhere to the matrix, medium, binder, or adhesive such that the particles are completely hidden.

[0078] In some examples, one or more functional powder particles on the surface of the composite material can provide a wider range of length scales on the composite surface compared to a wafer or substrate of nanostructures and can vary the physical properties of the material, as shown in FIGS. 7 and 8. For example, a composite composed of functional powder particles in a resin can absorb a wider range of electromagnetic radiation than a non-particle substrate such as a semiconductor wafer because of the presence of nano-scale and micro-scale features.

[0079] In some examples, one or more partially exposed functional powder particles can vary the mechanical properties of the composite material. The exposed nanostructures on the surface of the composite can be protected from damage due to their orientation relative to the particle core or the macro surface.

[0080] In some examples, one or more functional powder particles on the surface of the composite can increase the surface area of the composite surface. The composite surface area can exceed the surface area of a non-particle substrate such as a semiconductor wafer. A composite containing one or more exposed functional powder particles can have a greater functional density (functional surface area per contact area of the particles) when incorporating powder particles with a sufficient surface packing density.

[0081] Method for varying surface features In some examples, the disclosure provides a method for varying the features of a product, the method including incorporating one or more functional (e.g., crystalline, polycrystalline, semi-crystalline or amorphous) (e.g., semiconductor or insulator) powder particles into the product, where the powder particles optionally include one or more sub-millimeter structures selected from pores, depressions, craters, nanowires, cones, spires, rock columns, corals, cords, walls, fin-like portions, ridged portions, cliffs, pyramids and inverse pyramids, where the diameter of the powder particles is from 0.01 μm to 10,000 μm. The product can be any of the products described herein, such as a medical device, a cooking utensil, a fixture, a countertop, a vehicle, a boat, or an aircraft. The product can be selected from office consumables, office supplies, electronic devices, containers, kitchen utensils, cooking utensils, household items, textiles, hardware, consumer goods, vehicles and ships, filters, pumps, water appliances, surfaces, furniture, fixtures, devices, building materials, military supplies, tools, solar cells, currency, medical supplies, medical devices, paper products, manufacturing equipment, food processing equipment, and optical devices. In some embodiments, the product includes rubber, plastic, metal, glass, or ceramic. In some embodiments, the modifying step includes one or more of reducing the absorbance of visible light of the product, enhancing the absorbance of visible light of the product, enhancing the reflectance of light of the product, reducing the reflectance of light of the product, enhancing antibacterial properties, enhancing antifouling properties, enhancing hydrophobicity, enhancing hydrophilicity, enhancing electrical conductivity, enhancing electrical resistivity, enhancing luminescence, enhancing surface energy, reducing surface energy, increasing the coefficient of friction, and decreasing the coefficient of friction. The incorporating step may include coating the product with the powder particles or embedding the powder particles into the product.

[0082] Antibacterial use The functional particles of the present disclosure may be used to form an antibacterial surface. The antibacterial mode of action can be physical or chemical, including ultraviolet radiation, microwave radiation, and heating. The antibacterial functional particles described herein may exhibit one or more antibacterial modes of action. In some examples, nanostructures that can provide antibacterial activity may include nanowires, spires, cones, pores, rock pillars, corals, cords, walls, fin-like parts, ridge-like parts, cliffs, pyramids, inverted pyramids, and hybrid structures. The height of the nanowires for antibacterial activity can be in the range of 10 nm to 5 μm. In some embodiments, the height of the nanowires for antibacterial activity can be within 10 nm to 200 nm, 50 nm to 500 nm, 100 nm to 1 μm, 250 nm to 2 μm, or 500 nm to 5 μm. The diameter of the nanowires for antibacterial activity can be in the range of 10 nm to 1000 nm. In some embodiments, they can have a diameter of 10 nm to 100 nm, 50 nm to 250 nm, 100 nm to 500 nm, or 250 nm to 1000 nm. The elongation component, or the vertical component of the protrusion, of the cones, pores, rock pillars, corals, cords, walls, fin-like parts, ridge-like parts, cliffs, pyramids, inverted pyramids, and hybrid structures for antibacterial activity can be in the range of 1 nm to 5 μm. In some embodiments, the elongation component, or the vertical component of the protrusion, of the cones, pores, rock pillars, corals, grooves, fin-like parts, ridge-like parts, cliffs, pyramids, inverted pyramids, and hybrid structures for antibacterial activity can be within 1 nm to 200 nm, 50 nm to 500 nm, 100 nm to 1 μm, 250 nm to 2 μm, or 500 nm to 5 μm. The width along the narrow dimension of the cross-section of the elongation component, or the protrusion component, of the cones, pores, rock pillars, corals, grooves, fin-like parts, ridge-like parts, cliffs, pyramids, inverted pyramids, and hybrid structures for antibacterial activity can be in the range of 1 nm to 10,000 nm. In some embodiments, they can have dimensions of 1 nm to 100 nm, 50 nm to 250 nm, 100 nm to 500 nm, or 250 nm to 1000 nm.

[0083] Physical mode of action: Cells can be killed or lysed by physical interactions between the cell membrane and the surface of functional particles. The antibacterial activity and effectiveness can depend on specific types of structures on the particles in contact with the cell membrane. Without wishing to be bound by any particular theory, cells can be killed when the adhesive force between the functional particles and the cell membrane is greater than the cohesive force of the cell membrane. In some examples, viruses can be captured, immobilized, or inactivated by the interaction between the virus and the surface of functional particles.

[0084] In some examples, cells can be killed when adsorbed onto the surface of functional powder particles. The physical mode of cell death can vary depending on whether the surface is hydrophobic or hydrophilic. For example, functional powder particles with hydrophobic surfaces can attract the hydrophobic tails of lipids within the cell membrane and cause extraction of lipid molecules from the cell membrane. When a sufficient amount of lipid is extracted, the cell membrane can rupture and cause cell death. In some embodiments, functional powder particles with hydrophilic surfaces can adsorb the hydrophilic heads of membrane lipids, and as a result, the membrane may spread over the nanostructure surface. As the spread of the membrane increases, the membrane can become strained until it breaks and cause cell death. For both examples, the physical cause of cell death may not be related to penetration of the cell membrane by any nanostructures. In some examples, the hydrophobicity or hydrophilicity may be changed or amplified by further functionalizing the particles with a compound.

[0085] In some examples, the cell death rate (dead cells per unit time) or the cell lysis rate (lysed cells per unit time) can be increased by subjecting the antibacterial functional powder particles to a mechanical process. Any mechanical process may be selected such that it imposes an additional force on the cells, and as a result, it may bring about an increase in the attractive force between the functional powder and the cell membrane which may then cause cell membrane rupture. For example, one or more functional particles may be subjected to mechanical vibrations to rupture the cells. In some embodiments, one or more functional particles may be subjected to mechanical deformation to rupture the cells. In some examples, the mechanical deformation of the functional powder particles can be achieved by thermal cycle deformation, or piezoelectric deformation.

[0086] Chemical mode of action: In some examples, one or more functional powder particles can be subjected to one or more additional processes that add active antibacterial chemical components. Such surface functionalization can be aided by an increase in the surface area of the functional particles as compared to non-functional particles, wafers, or substrates. For example, one or more functional particles decorated with Ag or Cu nanoparticles can contain a composite material with antibacterial properties. In some examples, the metal nanoparticles can remain as residues from the MACE process. In some examples, the active antibacterial chemical components may be added to the functional particles. In some embodiments, the active chemical components may be added to structurally functionalized particles that do not have antibacterial properties. In some embodiments, the functional particles may be used as a vehicle for integrating chemical components into a composite.

[0087] Other physical modes of action: In some examples, one or more functional powder particles can be antibacterial when their chemical composition and crystal structure enable the emission of ultraviolet (UV) light. The UV light emission can be facilitated by applying an electric field or other methods. For example, the functional particles can contain InGaN, a UV-emitting semiconductor material. In some embodiments, InGaN, diamond carbon, BN, AlN, AlGaN, or AlGaInN can be selected as UV-emitting materials for antibacterial functional powder particles.

[0088] In some examples, the functional powder particles can enhance antibacterial properties in the presence of microwave radiation. Microwave radiation of sufficient intensity can kill cells. At lower intensities, microwave radiation can significantly damage cells. Microwave radiation can kill cells as a result of two or more cell damage mechanisms acting in concert in the presence of one or more antibacterial functional particles. Such embodiments can reduce the intensity of microwave radiation required to kill cells.

[0089] In some examples, one or more functional powder particles may be designed for efficient light absorption, thereby enhancing the antibacterial properties of the material. An efficient light absorber can convert light energy into heat and can cause cell damage or cell death of cells in contact with the material. In some examples, one or more functional powder particles may be designed to efficiently emit infrared radiation, thereby enhancing the antibacterial properties of the material. Irradiation of cells via infrared can promote sufficient heating and can damage or kill microorganisms. For example, GaAs particles may be selected as the particles to be functionalized due to the enhanced infrared (IR) emission spectrum of the material. In some embodiments, AlGaAs may be selected as the infrared emitting semiconductor particles.

[0090] In some examples, the functional powder particles can be selected such that the surface of the functional powder particles prevents cell adhesion. Such surfaces can inhibit or prevent the growth and replication of cells in contact with the composite surface.

[0091] Other exemplary uses Hydrophobic and hydrophilic surfaces: One or more functional particles described herein may be incorporated into the surface of a product to change the hydrophobicity or hydrophilicity of the surface. Surface energy, surface chemistry, and the nano- and micro-structure of the functional particles each affect the interaction between water and the macro surface. Suitable functional particles may be selected for a given application. For example, Figure 27 shows an example of the DI-H 2 O contact angle measurement results for a functional ABS plastic substrate. Samples 1, 2, 3, and 4 were structurally functionalized, resulting in a hydrophobic surface coating, while Sample 5 contained non-functionalized particles, resulting in a hydrophilic surface coating. The change in surface energy can be confirmed by comparing the contact angles of Samples 1, 2, 3, and 5, all of which have the same Si chemical composition and crystal structure, but the structural functionalization of Samples 1, 2, and 3 results in a larger contact angle. Chemical functionalization of the structurally functionalized particles may increase the hydrophobicity or antifouling properties of the coating.

[0092] Antireflective surface: One or more functional powder particles may be designed to create an antireflective surface. A significant amount of light is generally reflected at the steep surface / air interface of a given surface due to the difference in refractive index between the material and air. The functional particles may be designed with multi-directional microstructures and nanostructures to enhance the wide-angle antireflective properties of the material. Figure 37 shows the normal reflectance spectra at an incident angle of 45° (wavelengths of 190 - 900 nm) from an ABS plastic substrate coated via the method described in Example 16 with powders functionalized via the methods described in Example 2 (Sample E), Example 11 (Sample D), and Example 13 (Sample C). Non-functionalized Si particles (Sample F), an ABS plastic substrate coated via the method described in Example 16, the exposed ABS substrate, and a polished Si wafer are shown for reference. The average reflectance of Sample E shown in Figure 37 is 0.026% for light between 190 - 900 nm, 0.029% between 190 - 380 nm, 0.021% between 380 - 740 nm, and 0.033% between 740 - 900 nm. The average reflectance of Sample D shown in Figure 37 is 0.035% for light between 190 - 900 nm, 0.046% between 190 - 380 nm, 0.024% between 380 - 740 nm, and 0.045% between 740 - 900 nm. The average reflectance of Sample C shown in Figure 37 is 0.077% for light between 190 - 900 nm, 0.13% between 190 - 380 nm, 0.055% between 380 - 740 nm, and 0.062% between 740 - 900 nm. The average reflectance of Sample F shown in Figure 37 is 0.085% for light between 380 - 900 nm, 0.081% between 380 - 740 nm, and 0.095% between 740 - 900 nm. The reduction in reflectance between a surface containing non-functional Si powder particles (Sample F) and a surface containing functional particles (Samples C, D, and E) is significant over a wide range of wavelengths. For example, the average reflectance of Sample F between 380 - 740 nm is approximately 4 times that of Sample E. As seen in Figure 2, the hetero-functional particle morphology of Product E, which includes depressions and pores, aids in the antireflective properties over a wide range of wavelengths.Furthermore, these functional particle surface complexes prevent reflection over a wide angular range due to their nano-scale and micro-scale morphologies.

[0093] Light-absorbing surfaces: One or more functional powder particles may be designed to create a light-absorbing surface. One or more of the functional particles described herein may be embedded in the surface to form a material density gradient, which may result in a refractive index gradient that smoothly transitions between air and the bulk material. Such a gradient may be a broadband light absorber. In some embodiments, the anti-reflection material may be enhanced in light-absorbing properties by a plurality of light-scattering events that increase the number of interactions between photons and the functional powder particles. In some embodiments, a combination of hetero-functional forms may assist in broadband light absorption. For example, as seen in the broadband anti-reflection properties of Sample E shown in FIG. 37, and as seen in FIG. 2, it includes hetero-functional particles with a pitted and porous surface.

[0094] Fibers: For example, as depicted in FIG. 10, one or more functional powder particles may be embedded in synthetic or natural fibers. Such fibers may be used in fiber products, composites, or other materials. The functional powder may be selected to impart various properties on the fiber. Such applications serve to give the fiber properties including, but not limited to, antibacterial, hydrophobic, hydrophilic, anti-reflective, light-absorbing, antistatic, and improved durability.

[0095] Piezoelectric device: One or more functional powder particles may include a piezoelectric device, as shown, for example, in FIG. 11. In some examples, the functional semiconductor powder particles are embedded in an insulating material and physically contact a conductive material on one side of the insulator. Application of an electric field across the device may result in a mechanical change in the functional powder particles. Optionally, the device may enable detection of a mechanical force acting on the particles or the device due to a change in the electric field across the device. Optionally, the structural functionalization of the particles may change the lattice structure of the particles and thus their band structure, and may assist in the utilization of their piezoelectric properties.

[0096] Antistatic applications: One or more functional powder particles may be used to reduce charge accumulation. One or more functional particles embedded in a medium may reduce the overall resistance of the composite due to the electronic properties of the selected semiconductor. For example, one or more functional powder particles may be embedded in a plastic to reduce the charge accumulation of the plastic. Materials enabled for antistatic by incorporation of functional powder particles may be more resistant to dust accumulation and may reduce the likelihood of causing an electric shock. Optionally, one or more functional powder particles may be attached to the surface of a product and subsequently modified, coated, or plated with a conductive material. Microstructures and nanostructures will increase the capacitance per unit contact area. Microstructures and nanostructured shapes and protrusions may increase the discharge from the surface. FIG. 5(d) shows a cross-sectional SEM image of a rock pillar structure coated with Pt.

[0097] Isolated nanostructures: The prepared nanostructures can be collected from the surface of one or more functional powder particles by mechanical separation or other methods. In some examples, when the nanoscale properties of semiconductors or insulators are more desirable than the properties of functional powder particles with a wider range of nanoscale and microscale physical behaviors, the isolated nanostructures can be dispersed in a bulk medium. In some examples, layer-by-layer growth methods may be used to form an interface between one or more functional powder particles and another medium having nanostructures embedded in the surface. In such examples, the powder particle core can be separated from the nanostructures, and later, a medium with semiconductor or insulator nanoparticles embedded in the surface remains. The embedded nanostructures may be used as a catalyst for growing other structures on the surface of the medium.

[0098] Solar power generation devices: One or more functional powder particles may be applied as additives or components of solar power generation devices. For example, one or more p-type functional powder particles may be coated with an n-type semiconductor to produce a material for application in a solar power generation device. The size and shape of the functional powder particle nanostructures may change their band structure or bandgap, which may be due to quantum confinement. Therefore, the design of the functional powder particles may make it possible to vary the bandgap to be optimal for a solar power generation device. The nanostructures on the particle surface can increase light absorption through light scattering events and an increase in the refractive index gradient formed by the nanostructures and microstructures on the powder surface. Functional powder particles can absorb light over a larger range of angles over a wider bandwidth depending on the morphology and structure of their surface. The increase in the efficiency of light absorption is not limited to any particular nanostructure and can also be caused by some irregularities of the functional powder particles.

[0099] Optical detection device: In some examples, one or more functional powder particles may be used as additives or components of an optical detection device. The nanostructures on the particle surface can increase light absorption through light scattering events and an increase in the refractive index gradient formed by the nanostructures and microstructures on the powder surface. Functional powder particles can absorb light over a wider bandwidth and over a larger range of angles due to their surface texture and structure. The increase in the efficiency of light absorption is not limited to any specific nanostructure and can also be caused by some irregularities of the functional powder particles.

[0100] Light emitting device: In some examples, one or more functional powder particles may be used as additives or components of a light emitting device. For example, a light emitting diode (LED) device may include one or more particles of functional powder. Light extraction is an important aspect of LED efficiency because a large difference in reflectivity between the light emitting material and air can result in high internal reflection. The nanostructures on the surface of the functional powder particles can provide a refractive index gradient due to the material density gradient on the particle surface and can reduce the amount of internal reflection between the LED material and the air interface. For example, a porous pyramid structure on the powder surface would provide a material density gradient. A wide range of surface nanostructures and microstructures may be used for LED applications and are not limited to the structures described above.

[0101] Non-limiting examples: One or more functional particles of the present disclosure can be incorporated into many products, such as keyboards, computers, computer peripherals, computer mice, pressure-sensitive adhesive backing films, containers, bottles, utensils, cooking utensils, kitchen utensils, curtains, beverage dispensers, shopping carts, hydration packs, airbags, valves, pipe materials, and bags, fluid pipes, sewer pipes, gas pipes, footwear, telephones and peripherals, video game consoles and controllers, manned and unmanned vehicles, tires, buttons, holes, handrails, trains, awnings, cutting boards, drying racks, fluid tanks, drain pipes, pipe materials, filters, traps, nets, underwater vehicles, ships, and amphibious vehicles, refrigerators, freezers, biometric readers such as fingerprint readers and palm print readers and scanners, propellers, humidifiers, dehumidifiers, shower mats, exercise, gym, and yoga mats, sports equipment, liquid dispensers, handles and knobs, automated teller machines, credit cards and other plastic cards, trash cans, pet bowls, pet carriers, bulk transportation equipment, electronic devices, tiles, showers, toilets, trash and recycling containers, rails, floors, ceilings, walls, seat covers, tables, counters, chairs, cabinets, switches and switchboards, food preparation surfaces, food wraps, combs, brushes, razors, and grooming tools and supplies such as scissors, sinks, faucets, washbasins, bench tops, shelves, processing and packaging equipment and machinery, food and beverage processing and manufacturing equipment, meat processors, clothing, eyewear, bags, jet piers, docks, and pontoon pillars (pontoonequipment for water and marine use such as (pillars), marine and water pipes and cables, equipment for oil and gas, aircraft, military vehicles, military supplies and gears, shuttering, building materials, concrete, textiles / cloth, firearms, paints, surface coatings, wet suits, water appliances, lighting, solar cells, HVAC, telescopes, cameras and lenses, optical devices, photodetectors, tools, masks, grips, watches, coolers, transceiver radios, lockers, storage bins, large trash containers, packaging, squeegees, scaffolds, currency, musical instruments and devices, sewing tools, fishing gear, jewelry, blades, locks, washing machines and dryers, ovens, dishwashers, stoves, TVs, carpets, futons and bedding, rug mats, combat gears, pens, pencils, other writing utensils, office consumables, furniture, artworks, roofs, automobiles, medical equipment and measures, dental equipment and devices, bandages, baby beds, pacifiers, trays, toys, feeding bottles and accessories, thermometers, changing tables and covers for diapers, children's chairs, breast pumps, fuel pumps, charging stations, cords, bicycles, motorcycles, remote controls, mattresses, pools and peripheral devices, walkers / canes, school supplies, playground equipment, cafeteria equipment, hoses, tents, rainflys and tarps for rain shelters, umbrellas, gutters, grills, smokers, smoking devices, rubber products, plastic products, fittings, speakers, condoms, toothbrush holders, sponges, towels, pumps, ropes, biological analysis devices, biological cell component extraction / sampling devices, gloves, building components, office supplies, packaging, conveyor belts, manufacturing equipment, scooters, drones, cases, metal products, glass products, ceramic products, books, restaurant menus, paper and paper products, electrical cables, table mats, protective covers, and signs, including but not limited to. The products can be selected from office consumables, office supplies, electronic devices, containers, kitchen utensils, cooking appliances, household goods, textile products, hardware, consumer goods, vehicles and ships, filters, pumps, water appliances, surfaces, furniture, fittings, devices, building materials, military supplies, tools, solar cells, currency, medical supplies, medical devices, paper products, manufacturing equipment, food processing equipment, and optical equipment. Optionally, the products include rubber, plastic, metal, glass, or ceramic.

[0102] Method for creating a composite product Conventional techniques may be used to coat a product with one or more functional particles of the present disclosure. For example, an adhesive, binder, or similar material may be used to attach at least one functional particle to the product. The functional powder particles may be fully exposed, partially exposed, or fully embedded in an adhesive medium on the product surface.

[0103] Method of embedding functional particles in a thermoplastic: One or more functional powder particles may be added to a thermoplastic. In some examples, one or more heated functional powder particles may be added to the surface of a heated thermoplastic. The increase in temperature of the thermoplastic and the functional particles enables the thermoplastic to adsorb onto the particle surface. Optionally, the thermoplastic may contain functional powder particles within the bulk. The thermoplastic may be solidified such that the particles are partially adsorbed or fully absorbed into the plastic medium. Optionally, a plastic solution may be used to temporarily liquefy or melt the plastic. Optionally, powder coating, electrostatic coating, or a roll-to-roll method may be used to add the functional particles to the thermoplastic. The method of adding the functional particles to the thermoplastic is not limited to the methods described above.

[0104] Method for embedding functional particles in a molding material: In some examples, one or more functional powder particles are temporarily fixed to the inner surface of a mold or template. The mold or template is filled with a liquid or flexible material including glass, ceramic, concrete, elastomer, or metal. The molded or templated material is solidified and the mold or template is removed. In some examples, the molded or templated material will retain one or more functional powder particles embedded on the material surface. Optionally, the molded or templated material may not retain the particles, but will retain the traces of the nanostructures on the surface of one or more functional powder particles. In other examples, the molded or templated material will retain the nanostructured portions of one or more functional powder particles, while the original mold or template will retain the bulk portions of the powder particles.

Examples

[0105] Example 1: 10.0 g of crystalline Si powder with a purity of 99.995%, a particle size range of 10 μm - 150 μm, and an average particle size of 28 μm is suspended by stirring in an acetone bath for 10 minutes. Then, the acetone bath is sonicated for 10 minutes. The acetone / Si powder mixture is filtered and the Si powder is transferred to a methanol bath. The crystalline Si powder is suspended by stirring in the methanol bath for 10 minutes. Then, the methanol bath is sonicated for 10 minutes. The methanol / Si powder mixture is filtered and rinsed with DI-H 2 O. The powder is transferred and suspended by stirring in a solution of DI-H 2 O and 1.5 M HF to remove the native oxide. Then, the powder is filtered and rinsed with DI-H 2 O. Then, the Si powder is subjected to metal-assisted chemical etching (MACE). The Si powder is treated with 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2Suspend in a solution of O by stirring for 8 minutes to deposit Ag nanoparticles on the surface of the powder particles. Then, filter the powder and transfer it to a solution of 5.5 M HF, 2 M H 2 O 2 , and DI-H 2 O, and suspend by stirring for 30 minutes at an initial bath temperature of 25 °C. This reaction is exothermic, so the bath temperature can rise and accelerate the etching rate. After the MACE process, filter the Si powder, then rinse it thoroughly with DI-H 2 O, and then it may be dried with nitrogen gas to remove residual moisture. The resulting material is Si powder with a nanostructured surface.

[0106] Example 2: Functional Si powder is prepared by the method described in Example 1. Then, expose the functional Si particles to a bath of 7 M HNO 3 and DI-H 2 O for 5 minutes to remove and recover Ag from the Si particles. The Si powder is given a final rinse with DI-H 2 O, and then it may be dried with nitrogen gas to remove residual moisture. The resulting material is Si powder with a nanostructured surface. The recovered metal may be recycled for further use.

[0107] Example 3: Suspend 10.0 g of crystalline Si powder with a purity of 99.995%, a particle size range of 10 μm - 150 μm, and an average particle size of 28 μm in a bath of acetone by stirring for 10 minutes. Then, sonicate the acetone bath for 10 minutes. Filter the acetone / Si powder mixture and transfer the Si powder to a methanol bath. Suspend the crystalline Si powder in the methanol bath by stirring for 10 minutes. Then, sonicate the methanol bath for 10 minutes. Filter the methanol / Si powder mixture and rinse with DI-H 2 O. Transfer the powder and suspend it by stirring in a solution of DI-H 2 O and 1.5 M HF for 5 minutes to remove the native oxide. Then, filter the powder and DI-H 2Immediately with O. Then, apply the Si powder to MACE. The Si powder is placed in 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O solution and suspended by stirring for 8 minutes to deposit Ag nanoparticles on the surface of the powder particles. Then, the powder is filtered and transferred to a solution of 5.5 M HF, 2 M H 2 O 2 , and DI-H 2 O solution, and suspended by stirring for 25 minutes at an initial bath temperature of 25 °C. This reaction is exothermic, so the bath temperature rises and can accelerate the etching rate. After the MACE process, the Si powder is filtered and then rinsed thoroughly with DI-H 2 O.

[0108] Then, subject the Si powder to the next round of MACE. The Si powder is placed in 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O solution and suspended by stirring for 0.5 minute to deposit additional Ag nanoparticles on the surface of the powder particles. Then, the powder is filtered and transferred to a solution of 5.5 M HF, 2 M H 2 O 2 , and DI-H 2 O solution, and suspended by stirring for 15 minutes at an initial bath temperature of 25 °C. This reaction is exothermic, so the bath temperature rises and can accelerate the etching rate. After MACE, the Si powder is given a final rinse with DI-H 2 O, and then nitrogen gas can be applied to remove residual moisture. The resulting material is Si powder with a nanostructured surface.

[0109] Example 4: Functional Si powder is prepared by the method described in Example 3. Then, the functional Si particles are exposed to a bath of 7.85 M HNO 3 and DI-H 2 O for 5 minutes to remove and recover Ag from the Si particles. The Si powder is rinsed with DI-H 2Perform a final rinse with O, and then place it in a vacuum chamber to remove residual moisture. The resulting material is Si powder with a nanostructured surface. The recovered metal may be reused for further use.

[0110] Example 5: Crystalline Si powder with a particle size range of 10 μm - 200 μm is suspended in an acetone bath by stirring for 10 minutes. Then, the acetone bath is sonicated for 10 minutes. The acetone / Si powder mixture is filtered, and then the Si powder is transferred to a methanol bath. The crystalline Si powder is suspended in the methanol bath by stirring for 10 minutes. Then, the methanol bath is sonicated for 10 minutes. The methanol / Si powder mixture is filtered, and then the powder is transferred to a vacuum oven heated at 80 °C for at least 1 hour. Then, the Si powder is subjected to chemical etching (CE). The Si powder is stirred in a solution of 1.0 M KOH and DI-H 2 O at an initial bath temperature of 50 °C for 20 minutes. This reaction is exothermic, and thus the bath temperature rises, which can accelerate the etching rate. The resulting powder morphology and etching rate are determined by the bath temperature, duration, and stirring. Stirring the solution reduces the temperature gradient in the bath, resulting in more uniform functionalization between the particles. Optionally, a static bath may result in non-uniformly functionalized functional particles between the particles and may be advantageous for creating a dispersion of structurally functionalized particles in a single batch. After the CE process, the Si powder is filtered and rinsed thoroughly with deionized water.

[0111] Then, the Si powder is subjected to MACE. The Si powder is suspended by stirring for 5 minutes in a solution of 0.20 M HF, 0.05 M AgNO 3 , and DI-H 2 O to deposit Ag nanoparticles on the surface of the powder particles. Then, the powder is filtered and then in 5.5 M HF, 2 M H 2 O 2 , and DI-H 2Transfer to a solution of O and suspend by stirring for 30 minutes at an initial bath temperature of 25 °C. This reaction is exothermic, and thus the bath temperature will rise and can accelerate the etching rate. After the MACE process, filter the Si powder and then rinse it thoroughly with DI-H 2 O. Then, expose the Si particles to a bath of 7.85 M HNO 3 and DI-H 2 O for 5 minutes to remove and recover Ag from the Si particles. The Si powder is given a final rinse with DI-H 2 O and then placed in a vacuum chamber to remove residual moisture. The resulting material is Si powder with a nanostructured surface.

[0112] Example 6: 10.0 g of crystalline Si powder with a purity of 99.995%, a particle size range of 10 μm - 150 μm, and an average particle size of 28 μm is ultrasonically treated and suspended by stirring for 15 minutes each in baths of acetone and then methanol to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2 O. Transfer the powder to a filtration reactor and suspend it by stirring at 400 rpm for 5 minutes in a solution of DI-H 2 O and 1.35 M HF to remove the native oxide. Then, remove the solution from the reactor. Then, subject the Si powder to MACE. The Si powder is suspended by stirring at 400 rpm in a solution of 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O to deposit Ag nanoparticles on the surface of the powder particles. Then, remove the solution from the reactor after 8 minutes. Then, subject the powder to etching with a static etching solution initially at 25 °C containing 48% w / w HF, 30% w / w H 2 O 2 , and DI-H 2 O (1:1:3 v / v). Add H 2 O 2 continuously for the first 10 minutes. The etching duration, chemical concentration, temperature, and H 2 O 2The acceleration rate is varied according to the resulting nano-structured Si powder intended. The etching solution is removed from the reactor and then the powder is rinsed with DI-H 2 O or ethanol. Optionally, the powder is exposed to a bath of 7.85 M HNO 3 and DI-H 2 O for 5 minutes to remove Ag from the functionalized particles and then recovered. The recovered metal may be reused for further use. The powder is given a final rinse with DI-H 2 O or ethanol and then placed in an oven at 50 °C or in a vacuum chamber to remove residual moisture. Figure 4 shows an example of the resulting nanowire surface formed after 60 minutes of etching.

[0113] Example 7: 10.0 g of crystalline Si powder with a purity of 99.995%, a particle size range of 10 μm - 150 μm and an average particle size of 28 μm is sonicated and then suspended in a bath of acetone and then in a bath of methanol for 15 minutes each by stirring to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2 O. The powder is transferred to a filtration reactor and suspended in a solution of DI-H 2 O and 1.35 M HF by stirring at 400 rpm for 5 minutes to remove the native oxide. Then the solution is removed from the reactor. Then, the Si powder is subjected to MACE. The Si powder is suspended in a solution of 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O by stirring at 400 rpm to deposit Ag nanoparticles on the surface of the powder particles. Then the solution is removed from the reactor after 8 minutes. Then, the powder is suspended in an etching solution initially at 25 °C by stirring at 250 rpm. The powder-containing solution is stirred to prevent the formation of a film or bubbles or a skin at the solution / air interface. The film, bubbles, or skin may result in hetero-functionalized particles between the particles. The etching solution is 48% w / w HF, 30% w / w H 2 O 2 , and DI-H2 containing O(1:1:3 v / v), and adding H 2 O 2 continuously for the first 10 minutes. The etching duration, chemical concentration, temperature, stirring rate, and the addition rate of H 2 O 2 can be varied according to the resulting Si powder of the nanostructure intended. Figures 17, 16, and 5c and 5d respectively show examples of the resulting nanostructured surfaces with etching durations of 30 minutes, 60 minutes, and 90 minutes. Remove the etching solution from the reactor, and then rinse the powder with DI-H 2 O or ethanol. Optionally, suspend the powder in a solution of 7.85 M HNO 3 , and DI-H 2 O by stirring at 250 rpm for 5 minutes to remove and recover Ag from the functionalized particles. Remove the solution from the reactor, and then perform a final rinse of the powder with DI-H 2 O or ethanol.

[0114] The movement of the etching solution has a significant impact on the resulting nanostructures. For example, the nanostructures shown in FIGS. 4 and 16 were created from the procedures described in Example 6 and the above (Example 7). The etching conditions and etching duration are the same except for not stirring the etching solution (Example 6) and stirring it (Example 7). However, FIG. 4 shows a morphology containing nanowires, while FIG. 16 shows a morphology containing coral structures. Furthermore, the resulting etching depth (the distance between the surface and the outer end of the unetched solid particle core) is, for the same duration, as seen in FIG. 32, ten times deeper when the etching solution is static than when the etching solution is stirred at 250 rpm. As a result, the etching depth rate (etching depth / time) is approximately ten times greater when the etching solution is static than when stirred at 250 rpm. In the static case, Ag nanoparticles move along a relatively straight path from the surface of the Si particles towards the particle core, thereby forming the high aspect ratio nanowires shown in FIG. 4. On the other hand, the agitation and movement during etching may introduce additional forces onto the Ag nanoparticles during their movement towards the Si particles, thereby causing changes to the movement and the resulting etched structure. As confirmed in FIG. 16, stirring may result in irregular coal structures with a low aspect ratio.

[0115] The nanowire structures formed via the method described in Example 6 are structurally more delicate than the structures formed via the method described in Example 7. For example, separately stirring the particles at 250 rpm for 5 minutes in solution resulted in significant damage and loss of nanowires from the particles of Example 6. On the other hand, the interconnected structures found on the particles of Example 7 did not show significant degradation due to being stirred in solution or by normal handling. Furthermore, FIG. 4 shows particles that did not undergo additional stirring, but there are no nanowires (functional structures) destroyed by normal handling in the section of the particle surface. Interconnected structural features found in structures such as, but not limited to, rock columns and corals provide mechanical durability.

[0116] Figure 25 shows the X-ray diffraction data from the functional powder particles after 90 minutes of etching, as well as non-functional Si particles for comparison. A displacement in the peak positions can be confirmed for the Si(111) and Si(311) peaks of the functional powder, indicating a lattice elongation of 0.194% along the <111> direction and a lattice contraction of 0.143% along the <311> direction. On the other hand, the positions of the Si(220), Si(400), and Si(331) peaks remain unchanged. This X-ray data suggests that the crystal unit cell is anisotropic and has been deformed by the structural functionalization of the particles.

[0117] Example 8: Functional Si powder is prepared by the method described in Example 7 with an etching duration of 90 minutes. The powder is added to H 2 SO 4 and H 2 O 2 (4:1 v / v) for 25 minutes to remove organic residues and prepare silanol groups on the surface. The powder is filtered and DI-H 2Rinse thoroughly with O and then dry at 75 °C for 30 minutes. Add the powder to a 2.5 mM solution of octadecyltrichlorosilane prepared in toluene and react for 120 minutes. Thereafter, the chemically functionalized powder is removed from the solution by filtration and rinsed with chloroform. Figure 28 shows the attenuated total reflection Fourier transform infrared spectra (ATR-FTIR) of chemically and structurally functionalized Si powder (Sample D), structurally functionalized Si powder (Sample C), chemically functionalized Si powder (Sample B), and non-functionalized Si powder (Sample A). Based on the peak positions of symmetric and asymmetric C-H stretches, both of the two chemically functionalized powders (Samples B and D) show ordered monolayer formation. However, at least a three-fold increase in absorbance is seen in the structurally and chemically functionalized powder (Sample D), which corresponds to a greater number of functional molecules per particle as a result of the larger surface area of the structurally functionalized particles. Furthermore, this result indicates that the structurally functionalized particles (Samples C and D) have at least three times the surface area of the non-functionalized Si particles (Samples A and B). Chemical functionalization may further increase the hydrophobicity of the structurally functionalized particles. Typically, structurally functionalized particles allow for a greater amount of chemical functionalization due to their larger surface area compared to non-functionalized particles.

[0118] Example 9: 10.0 g of crystalline Si powder with a purity of 99.995%, a particle size range of 10 μm - 150 μm, and an average particle size of 45 μm is sonicated and then suspended in acetone and then a methanol bath for 15 minutes each by stirring to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2 O. Transfer the powder to a filtration reactor and suspend it in a solution of DI-H 2 O and 1.35 M HF by stirring at 400 rpm for 5 minutes to remove the native oxide. Thereafter, remove the solution from the reactor. Thereafter, subject the Si powder to one-step MACE. The Si powder is treated with 4.6 M HF, 0.55 M H 2 O 2, 0.035 M of Cu(NO 3 ) 2 ·2.5H 2 O, and a solution of DI-H 2 O are used to suspend by stirring at 250 rpm to deposit Cu nanoparticles on the surface of the powder particles and then etch the particles. The solution is initially at 25 degrees. The etching duration, chemical concentration, temperature, and stirring speed may be varied according to the resulting nanostructured Si powder intended. Figures 20(a) and 20(b) show examples of the resulting nanostructured surfaces with etching durations of 30 minutes and 10 minutes, respectively. The etching solution is removed from the reactor and then the powder is rinsed with DI-H 2 O or ethanol. Optionally, the powder is suspended by stirring at 250 rpm for 5 minutes in a solution of 7.85 M HNO 3 and DI-H 2 O to remove Cu from the functionalized particles and then recovered. The recovered metal may be reused for further use. The solution is removed from the reactor and then the powder is given a final rinse with DI-H 2 O or ethanol.

[0119] Example 10: 10.0 g of crystalline Si powder with a purity of 99.995% and a particle size range of 10 μm - 150 μm and an average particle size of 45 μm is ultrasonically treated and then suspended by stirring in a bath of acetone and then in a bath of methanol for 15 minutes each to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2 O. Then, the powder is suspended by stirring at 250 rpm in an etching solution initially at 25 °C. The powder-containing solution is stirred to prevent the formation of a film or foam or skin at the solution / air interface. The etching solution is 6.7 M KOH and DI-H 2It consists of O. The temperature of the solution rises during the reaction, and the temperature measured by an IR thermometer at the upper surface of the solution after 9 minutes was 55 °C. The etching duration, chemical concentration, and solution temperature may be varied according to the resulting nanostructured Si powder intended. Figure 21 shows an example of the resulting nanostructured surface produced after 9 minutes. The etching solution is removed from the reactor, and then the powder is rinsed with DI-H 2 O or ethanol.

[0120] Example 11: 10.0 g of crystalline Si powder with a particle size range of 75 - 150 μm and a purity of 99.995% is ultrasonically treated and suspended in an acetone bath and then in a methanol bath for 15 minutes each by stirring to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2 O. Then, the powder is suspended in the etching solution by stirring at 250 rpm. The etching solution consists of 5% (w / w) NaOH and DI-H 2 O and is initially at 60 °C. The temperature measured by an IR thermometer at the upper surface of the solution rises with a maximum temperature of 71 °C in the first 5 minutes and then decreases in the next 55 minutes to a final temperature of 33 °C. The etching duration, chemical concentration, and solution temperature may be varied according to the resulting structured Si powder intended. Figure 22 shows an example of the resulting nanostructured surface produced after 15 minutes. The particles are removed by filtration, and the powder is rinsed with DI-H 2 O or ethanol.

[0121] Example 12: 10.0 g of crystalline Si powder with a particle size range of 75 - 150 μm and a purity of 99.995% is ultrasonically treated and suspended in an acetone bath and then in a methanol bath for 15 minutes each by stirring to remove organic contaminants. The washed Si powder is filtered and rinsed with DI-H 2Immediately with O. Then, the powder is suspended in the etching solution by stirring at 250 rpm. Stir the powder-containing solution to prevent the formation of a film or foam or skin at the solution / air interface. The etching solution consists of 1% (w / w) KOH and DI-H 2 O, initially at 60 °C and then not heated. The etching duration, chemical concentration, and solution temperature may be varied according to the resulting Si powder of the intended structure. Remove the solution from the reactor after 70 minutes and wash the powder with DI-H 2 O and then remove it from the reactor. Then, subject the Si powder to MACE. The functional Si powder is suspended in a solution of 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O by stirring at 400 rpm to deposit Ag nanoparticles on the surface of the functional powder particles. Then, remove the solution from the reactor after 8 minutes. Then, suspend the powder in an etching solution initially at 25 °C by stirring at 250 rpm. This reaction is exothermic and the peak temperature measured by an IR thermometer at the upper surface of the solution is 85 °C in 5 minutes. Stir the powder-containing solution to prevent the formation of a film or foam or skin at the solution / air interface. The etching solution contains 48% w / w HF, 30% w / w H 2 O 2 , and DI-H 2 O (1:1:3 v / v) and H 2 O 2 is added continuously for the first 9 minutes. The etching duration, chemical concentration, solution temperature, and stirring rate may be varied according to the resulting micro- and nanostructured Si powder of the intended structure. Figure 23 shows an example of the resulting heterofunctionalized surface produced after 15 minutes. Remove the solution from the reactor and rinse the powder with DI-H 2 O or ethanol. Optionally, the powder is treated with 7.85 M HNO 3 , and DI-H 2Suspend in an O solution by stirring at 250 rpm for 5 minutes to remove Ag from the functional particles and then recover it. The recovered metal may be reused for further use. Remove the solution from the reactor and then rinse the powder with DI-H 2 O or ethanol for the final rinse.

[0122] Example 13: Transfer 10.0 g of 99% pure amorphous SiO powder with a particle size range of 38 - 45 μm to a filtration reactor. Then, subject the SiO powder to MACE. Suspend the SiO powder in a solution of 0.15 M HF, 0.035 M AgNO 3 , and DI-H 2 O by stirring at 400 rpm to deposit Ag nanoparticles on the surface of the powder particles. Then, remove the solution from the reactor after 8 minutes. Then, suspend the powder in an etching solution initially at 25°C by stirring at 250 rpm. This reaction is exothermic, and the peak temperature measured by an IR thermometer at the upper surface of the solution is 83°C in 2 minutes. Stir the powder-containing solution to prevent the formation of a film or foam or skin at the solution / air interface. The etching solution contains 48% w / w HF, 30% w / w H 2 O 2 , and DI-H 2 O (1:1:3 v / v), and continuously add H 2 O 2 for the first 7.5 minutes. The etching duration, chemical concentration, solution temperature, and stirring rate may be varied according to the resulting nanostructured SiO powder intended. Figure 33 shows an example of the resulting nanostructured surface for an etching duration of 60 minutes. Remove the etching solution from the reactor and then rinse the powder with DI-H 2 O or ethanol. Optionally, suspend the powder in a solution of 7.85 M HNO 3 , and DI-H 2 O by stirring at 250 rpm for 5 minutes to remove Ag from the functional particles and then recover it. The recovered metal may be reused for further use. Remove the solution from the reactor and then rinse the powder with DI-H2 Perform a final rinse with O or ethanol.

[0123] Example 14: 3.0 g of crystalline Si powder with a purity of 99%, consisting of α-phase and β-phase shown by X-ray diffraction in Fig. 26, with an average particle size of 40 μm, is transferred to a reactor containing 48% w / w HF and HNO 3 (3:1 v / v), initially heated to 80 °C and then maintained at 75 - 100 °C. Then, the powder is suspended in the etching solution by stirring at 241 rpm. Stir the powder-containing solution to prevent the formation of a film or foam or skin at the solution / air interface. The etching duration, chemical concentration, solution temperature, and stirring rate may be varied according to the resulting intended nanostructured SiC powder. Fig. 24 shows an example of the resulting nanostructured surface after 150 minutes of etching. The particles are removed by filtration, and the powder is rinsed with DI-H 2 O or ethanol.

[0124] Example 15: 3.3 g of crystalline Ge powder with a purity of 99.999% and a particle size of less than 150 μm is transferred to a reactor and suspended in a solution of DI-H 2 O and 1.35 M HF by stirring at 400 rpm for 5 minutes to remove the native oxide. Then, the solution is removed from the reactor. Then, the Ge powder is subjected to MACE. The Ge powder is suspended in a solution of 0.14 M HF, 0.035 M AgNO 3 , and DI-H 2 O by stirring at 400 rpm to deposit Ag nanoparticles on the surface of the powder particles. Then, the solution is removed from the reactor after 8 minutes. Then, the powder is suspended in an etching solution initially at 25 °C by stirring at 250 rpm. This reaction is exothermic, and the temperature measured by an IR thermometer at the upper surface of the solution is 55 °C in 12 minutes. Stir the powder-containing solution to prevent the formation of a film or foam or skin at the solution / air interface. The etching solution is 48% w / w HF, 30% w / w H 2 O 2 , and DI-H2 Containing O(1:1:3 v / v), and H 2 O 2 is continuously added for the first 6 minutes. The etching duration, chemical concentration, solution temperature, and stirring speed may be varied according to the resulting intended nanostructured Ge powder. Figures 35 and 36 show the functionalized surfaces resulting from a 5-minute etching duration. Remove the etching solution from the reactor, and then rinse the powder with DI-H 2 O or ethanol. Optionally, suspend the powder in a solution of 7.85 M HNO 3 and DI-H 2 O, and stir at 250 rpm for 5 minutes to remove Ag from the functional particles and recover it. The recovered metal may be reused for further use. Remove the solution from the reactor, and then perform a final rinse of the powder with DI-H 2 O or ethanol.

[0125] Example 16: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The functional powder is attached to the plastic by temporarily liquefying the plastic with a chemical solvent. Examples of plastic solvents include, but are not limited to, dichloromethane, benzene, toluene, n-hexane, hexane, petroleum ether, acetone, acetalaldehyde, methanol, aniline, carbon tetrachloride, cyclohexane, diethyl ether, xylene, methyl ethyl ketone, methyl acetate, trichloroethylene, methyl methacrylate monomer. The solvent and the functional powder may be applied to the plastic in any order or simultaneously. Thereafter, the solvent is evaporated and the plastic is solidified. As illustrated in FIGS. 9(b) and 9(c), the resulting composite consists of the functional powder attached on and / or within the plastic surface and can have a complex form or shape (in contrast, a structurally functionalized rigid wafer would not be able to accommodate a complex surface shape). The surface of the functional powder may be partially exposed at the plastic / atmosphere interface. FIG. 38 shows an example of a functionalized surface including an ABS plastic substrate coated with functional particles via a plastic solvent. Optionally, the powder may be electrostatically applied to the surface of the plastic.

[0126] Example 17: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The plastic is heated to an excessive temperature and temporarily melted. Subsequently, the functional powder is deposited and the plastic is solidified while the powder is attached on and / or within the product. As illustrated in FIGS. 9(b) and 9(c), the resulting bulk and / or surface composite consists of the functional powder attached on and / or within the plastic surface. The surface of the functional powder may be partially exposed at the plastic / atmosphere interface. Optionally, the powder may be electrostatically applied to the surface of the plastic.

[0127] Example 18: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. A binder medium is applied to the surface of the product. The binder may be applied by spraying, rolling, coating, brushing, stamping, or any other deposition technique. The functional powder is deposited on the binder medium, and then a product coated with functional powder particles partially exposed at the surface / atmosphere interface is left as shown in Fig. 9(a). Optionally, a paint may be used as the binder medium.

[0128] Example 19: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. An acrylic paint, or another polymer paint (or coating) is applied to the surface of the product. Subsequently, the functional powder is applied to the painted surface by temporarily liquefying the paint with a chemical solvent. Examples of plastic solvents include, but are not limited to, dichloromethane, benzene, toluene, hexane, hexanes, petroleum ether, acetone, acetal aldehyde, methanol, aniline, carbon tetrachloride, cyclohexane, diethyl ether, xylene, methyl ethyl ketone, methyl acetate, trichloroethylene, methyl methacrylate monomer. The solvent and the functional powder may be applied to the painted surface in any order or simultaneously. Then, the solvent is evaporated and the paint is solidified. The resulting composite consists of the functional powder applied to the painted surface. As shown in Fig. 9(a), the surface of the functional powder may be partially exposed at the paint / atmosphere interface. Optionally, the powder may be electrostatically applied to the surface of the paint.

[0129] Example 20: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The functional powder is suspended in a metal-adhering paint via stirring. The paint is applied to the working surface of a set of medical devices or equipment to form a thin layer. The paint is dried, and then, as illustrated in Fig. 9(a), a metal surface coated with functional powder particles partially exposed at the paint / atmosphere interface is left.

[0130] Example 21: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The functional powder is temporarily fixed to the inner surface of a mold for casting a product such as a medical device or equipment. The mold is filled with a liquid plastic, and then the plastic is solidified. The functional powder particles are embedded in the plastic surface, where the nanostructures may be partially exposed to the atmosphere.

[0131] Example 22: A functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The powder is suspended in a metal-adhering paint via stirring. The paint is applied to the outer surface of a watercraft to form a thin layer. The paint is dried, and then, a metal surface coated with functional powder particles partially exposed at the paint / atmosphere interface is left. Due to the presence of nano- and micro-structures on the watercraft surface, the hull may have antifouling and hydrophobic properties that prevent barnacles and aquatic organisms from adhering to the surface of the watercraft and function to reduce drag.

[0132] Example 23: The functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. Using conventional powder coating techniques, the thermosetting polymer particles are applied to the surface via charging. Subsequently, the functional powder is applied to the surface. Optionally, the functional powder may be applied to the surface via charging. Then, the product is cured with heat to attach the functional particles to the product surface. The thermosetting polymer acts as a binder between the base and the functional particles. The surface of the functional powder may be partially exposed at the paint / atmosphere interface.

[0133] Example 24: The functional powder is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. At least a part of the metal product is temporarily melted via heat. Subsequently, the functional powder is applied to the molten metal. The metal is solidified while attaching the functional particles to the metal product.

[0134] Example 25: A functional powder is prepared via the method described in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. A sterile, predetermined amount of the functional powder is added to a sterile reactor or the sterile functional powder is attached to the inner surface of a sterile reactor. Cells such as Escherichia coli (E. coli) or Candida albicans (C. albicans) in an aqueous solution (e.g., 500 μL) such as a nutrient broth (or another solution such as NaCl (e.g., 0.14 M)) are added to the reactor containing the functional particles. The reactor is then closed and the entire system is stirred / vortexed (e.g., for 30 seconds). Optionally, after stirring / vortexing, the reactor is allowed to stand (e.g., for up to 1 hour) to precipitate the contents or the reactor is centrifuged to assist in separating the contents. Figure 30 shows an example of an illustrative depiction of this method. The functional particles can increase the cell lysis rate and enable the extraction of intracellular components including, but not limited to, DNA, RNA, macromolecules, proteins, organelles, and metabolites. These intracellular components can then be utilized in downstream analysis, experimental protocols, or assays. Optionally, the functional particles can also be chemically functionalized to assist in lysis and / or intracellular component extraction.

[0135] Cell lysis by non-functional particles (e.g., bead beating) may require a longer stirring / vortexing duration compared to functional particles. This is because cell lysis depends on the ballistic interaction between non-functional particles and cells, which may heat up the reactor and temperature-sensitive contents. On the other hand, cell lysis by functional particles also involves interaction with the particle surface structure and can thus assist in the lysis process. Functional particles can lyse cells with less mechanical energy, thus reducing the heat load or heat transfer to the vessel and its contents as a result (and thus reducing damage to intracellular components).

[0136] In one example, functional particles were prepared via the method described in Example 7, with an etching duration of 60 minutes and residual Ag removed. These functional particles were sterilized and added to a sterile reactor together with Escherichia coli in 500 μL of LB broth (OD600 1.1). The reactor was vortexed for 30 seconds and then left standing at 37 °C for 1 hour. Compared to using non-functional Si particles, the functional Si particles showed a 533% increase in lysed Escherichia coli, as seen in Figure 31. The non-functional Si particles lysed 9% of the cells via ballistic interactions. On the other hand, the functional Si particles lysed 57% of the cells via an additional mechanism through the interaction between the functional surface structure and the cell membrane. Optionally, other types of cells may be lysed by this method. The volume, duration, and intensity of the solution with respect to stirring may be varied according to the application.

[0137] Example 26: Prepare the surface of the product via the methods described in Examples 16, 17, 18, 19, 23, or 24. The exposed texture of the functional particles may have antibacterial properties that physically disrupt colony formation or kill microorganisms. Figure 29 shows a fluorescence microscope image of an exemplary Z-stack composition of a surface prepared on an ABS plastic substrate via the method described in Example 16, with the functional particles prepared via the method described in Example 7, an etching duration of 60 minutes, and residual Ag removed. The viability of the cells was measured using the BacLight Live / Dead Fluorescent Kit (L7012 made of Propidium Iodide and SYTO9 components) according to the manufacturer's recommended method. Taking the average across the microscopic photographs of three functional surfaces, 89 ± 6% of Escherichia coli (adjusted to OD600 0.3) were killed after 1 hour of contact under optimal growth conditions (37 °C). The results indicate that the bacteria were killed by physical interaction between the functional particle surface structure and the bacterial membrane, which is independent of resistance promoting chemical antibacterial properties. Optionally, the functional particles may be further chemically functionalized to disrupt colony formation or kill microorganisms. Optionally, the particles may be further functionalized with a functionalizing compound to vary or amplify hydrophobicity or hydrophilicity.

[0138] Example 27: Prepare the functional powder particles via the methods described in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. The functional particles have a larger surface roughness than their non-functional counterparts over many length scales and may be used to abrade or polish other materials. For example, the abrasive functional particles may be used as abrasives in spray coating, abrasive tumbling.

[0139] Example 28: The composite product is prepared via the method described in Examples 16, 17, 18, 19, 23, or 24. The functional particles have a surface roughness that is greater than that of the non-functional equivalents over many length scales and may be used to abrade or polish other materials. The functional particles and their use are selected by their abrasion or polishing properties. The product may be used to abrade or polish other materials or products.

[0140] Example 29: Prepare the antireflective surface via the method described in Examples 16, 17, 18, 19, 23, or 24. For example, FIG. 37 shows data of the normal reflectance (wavelengths from 190 to 900 nm) from several surfaces at an incident angle of 45°. The samples are functional powder particles prepared via the method described in Example 2 (Sample E), Example 11 (Sample D), and Example 13 (Sample C), and non-functional Si powder particles (Sample F), and an ABS plastic substrate coated via the method described in Example 16. The exposed ABS substrate (Sample B) and the polished Si wafer (Sample A) are shown for reference. The average reflectance of Sample E shown in FIG. 37 is 0.026% for light between 190 - 900 nm, 0.029% for light between 190 - 380 nm, 0.021% for light between 380 - 740 nm, and 0.033% for light between 740 - 900 nm. The average reflectance of Sample D is 0.035% for light between 190 - 900 nm, 0.046% between 190 - 380 nm, 0.024% between 380 - 740 nm, and 0.045% between 740 - 900 nm. The average reflectance of Sample C is 0.077% for light between 190 - 900 nm, 0.13% between 190 - 380 nm, 0.055% between 380 - 740 nm, and 0.062% between 740 - 900 nm. The average reflectance of Sample F is 0.085% for light between 380 - 900 nm, 0.081% between 380 - 740 nm, and 0.095% between 740 - 900 nm. The reduction in reflectance between the surface containing non-functional Si powder particles (Sample F) and the surface containing functional particles (Samples C, D, and E) is significant over a wide range of wavelengths. For example, the average reflectance of Sample F between 380 - 740 nm is approximately 4 times that of Sample E. Further, these functional particle surface composites prevent reflection over a wide angular range due to their nano-scale and micro-scale morphologies.

[0141] Example 30: Adjust the antifouling surface, or hydrophobic surface, via the methods described in Examples 16, 17, 18, 19, 23, or 24. The microscale and nanoscale organization formed on the surface by the functional particles changes the surface energy of the product. For example, FIG. 27 shows the contact angle measurements of an ABS plastic substrate functionalized via attached functional Si particles, functional SiO particles, and non-functional Si particles. A polished Si wafer and an exposed ABS substrate are shown for comparison. The functional ABS plastic substrate was prepared via the method described in Example 16 and spread 100% on the inspection surface. The Si wafers and particles on Samples 1, 2, 3, 4, and 5 contain native oxide. Samples 1, 2, 3, and 4 contain functional particles and have contact angles greater than 90°, indicating that these surfaces are hydrophobic. The exposed ABS substrate, polished Si wafer, and Example 5 have contact angles less than 90°, indicating that these surfaces are hydrophilic. The alteration to the surface energy can be confirmed by comparing the contact angles of the polished Si wafer, Sample 1, Sample 2, Sample 3, and Sample 5, all of which have the same Si chemical composition. The microscale organization formed by Sample 5 of the non-functional Si particle surface shows an increase in the contact angle compared to the Si wafer. Samples 1, 2, and 3 show an increase in the contact angle due to their functional surface structures. The combination of low surface energy, hydrophobicity, and the antimicrobial properties of some functional particles may result in antifouling activity. Optionally, chemical functionalization may increase the hydrophobicity or antifouling properties of the coating.

[0142] Example 31: Prepare the surface via the method described in Examples 16, 17, 18, 19, 23, or 24. Subsequently, apply a conductive material to the exposed functional particles via conventional techniques to form a conductive surface having a surface area at least twice that of the contact portion. The micro- and nanoscale structures will increase the capacitance per one contact portion area. The micro- and nanoscale shapes may increase the discharge from the surface. FIG. 5(d) shows an example of a cross-sectional SEM image of a Pt-coated rock pillar structure.

[0143] Example 32: The band structure of the functional powder is varied by preparing functional powder particles via the method described in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. Structural functionalization may result in anisotropic expansion and contraction of the crystal lattice, which may in turn result in a change in the band structure of the particles. The anisotropic lattice modification may be localized to the portion of the particles that are structurally functionalized (i.e., radially dependent), or may change the entire particle (i.e., radially independent). In this way, the band structure can be altered without changing the chemical composition of the particles. For example, FIG. 25 shows X-ray diffraction data from non-functional Si particles and functional powder particles prepared by etching for 90 minutes via the method described in Example 7. A displacement in the peak positions can be confirmed for the Si(111) and Si(311) peaks of the functional powder, indicating a 0.194% lattice elongation along the <111> direction and a 0.143% lattice contraction along the <311> direction. On the other hand, the positions of the Si(220), Si(400), and Si(331) peaks remain unchanged. This X-ray data suggests that the crystal unit cell is anisotropic and has been deformed for the entire particle (average diameter 45 μm) by structural functionalization at the surface (thickness 1.5 μm). If the lattice modification were radiation dependent, it would have resulted in multiple component Bragg peaks (due to the contribution of X-ray scattering from the particle core and the functionalized region), which is not present in the X-ray data. By structurally functionalizing a relatively small portion of the particles without changing the chemical composition, the crystal lattice of the entire particle was changed.

[0144] Example 33: An opaque pigment resistant to color fading is prepared via the method described in Example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. Some pigments fade depending on the chromophore due to exposure to high-energy radiation (such as ultraviolet light) that damages the color-bearing molecules. The optical properties of the functional particles depend on both the bulk material properties and its particle surface structure. For example, samples A, C, E, and F in FIG. 37 have the same bulk composition and crystal structure but different surface morphologies. Different surface structures have an important influence on the light reflectivity and the appearance of the surface. The matte black appearance of sample E is due to the functional structure of the particles that structurally absorb light. Structurally functionalized particles used as pigments may be more resistant to fading because the color is not determined solely by the molecular structure.

[0145] Preferred embodiments of the invention have been shown and described herein, but it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many variations, changes, and substitutions will occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be utilized in practicing the invention. The following claims define the scope of the invention, and it is intended that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

1. 1. A method for forming structures on powder particles, the method comprising: (a) providing powder particles of one or more crystalline, polycrystalline, semi-crystalline, or amorphous semiconductors or insulators; (b) (e.g., optionally) removing surface contaminants from one or more powder particles; (c) (e.g., optionally) removing oxides from one or more powder particles; (d) forming a first type structure on one or more powder particles, thereby forming one or more homofunctional powder particles; (e) (e.g., optionally) forming a second type of structure on the one or more homofunctional powder particles, thereby forming one or more heterofunctional powder particles; A method wherein the first and second type structures are (e.g., optionally) selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverted pyramids.

2. 2. The method of claim 1, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

3. The method of claim 1 or 2, wherein the powder particles include one or more grains.

4. The method of claim 3 , wherein the powder particles consist of single crystal grains.

5. 5. The method of claim 1, further comprising the step of: (b) removing surface contaminants from one or more powder particles.

6. 6. The method of claim 1, further comprising the step of: (c) removing oxides from one or more of the powder particles.

7. 7. The method of claim 1, further comprising: (e) forming a second type of structure on the one or more homofunctional powder particles, thereby forming one or more heterofunctional powder particles.

8. 8. The method of claim 1, wherein the forming step of (d) comprises forming structures of the first type on the surface of the powder particles or within the pores.

9. 9. The method of claim 1, wherein the forming step of (e) comprises forming structures of a second type on the surface of the powder particles or within the pores.

10. 10. The method of claim 1, wherein at least one of the forming steps (d) and (e) comprises lithography.

11. 11. The method of any one of claims 1 to 10, wherein each of the forming steps (d) and (e) independently comprises a process selected from metal assisted chemical etching and chemical etching.

12. At least one of the forming steps (d) and (e) includes a metal assisted chemical etch, the metal assisted chemical etch comprising: depositing metal ions on the surfaces of the powder particles; and etching the powder particles by exposing the powder particles to metal ions in an etching solution.

13. The method of claim 12 , wherein the metal ions are selected from precious metal ions or noble ions.

14. The method of claim 12 or 13, wherein the etching solution is a plasma, a gas or a solution.

15. The method according to claim 12 or 13, wherein the etching solution is a solution comprising an etching solution and an oxidizing agent.

16. 16. The method of claim 1, wherein the first type of structures are sub-millimeter structures.

17. The method of claim 16 , wherein the first type of structures are selected from microstructures and nanostructures.

18. 18. The method of claim 1, wherein the second type of structures are sub-millimeter structures.

19. The method of claim 18 , wherein the second type of structures are selected from microstructures and nanostructures.

20. 20. The method of any one of claims 1 to 19, further comprising exposing the one or more functional powder particles to a process selected from film coating, plating, chemical functionalization, doping, nanoparticle decoration, lithography, and combinations thereof.

21. 21. The method of any one of claims 1 to 20, wherein the first and second type structures are selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, grooves, fins, ridges, cliffs, pyramids and inverted pyramids.

22. A surface (e.g., of an article), the surface comprising one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles (e.g., comprising one or more particles configured on the surface and / or one or more particles embedded in the surface) (e.g., the article comprises one or more such particles in and / or on the surface but not in the bulk material, or the article comprises one or more such particles in a bulk material having the surface (and comprising particles in and / or on the surface)), the powder particles (e.g., optionally) comprising one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and the powder particles have a diameter of 0.01 to 10,000 microns.

23. 23. The surface of claim 22, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

24. 24. The surface of claim 22 or 23, wherein the powder particles include one or more grains.

25. 25. The surface of claim 24, wherein the powder particles consist of single crystal grains.

26. 26. The surface of any one of claims 22 to 25, wherein the powder particles have a diameter of 0.1 to 1,000 microns.

27. 27. The surface of any one of claims 22 to 26, wherein the powder particles comprise two or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, fins, ridges, cliffs, pyramids, and inverted pyramids.

28. 28. The surface of any one of claims 22 to 27, wherein the one or more structures are sub-millimeter structures.

29. 30. The surface of claim 28, wherein the one or more structures are selected from microstructures and nanostructures.

30. 30. The surface of claim 22 or 29, wherein the average diameter of the smallest 30% of the powder particles is 200% smaller than the average diameter of the largest 10% of the powder particles.

31. 31. The surface of any one of claims 22 to 30, further comprising a film separating the powder particles from the atmosphere.

32. 32. The surface of any one of claims 22 to 31, wherein the surface is antireflective, reflective, adsorptive, conductive, insulating, antistatic, luminescent, antibacterial, non-wettable, hydrophobic, hydrophilic, antifouling, abrasive, anti-adherent, anti-slip, or a combination thereof.

33. 33. The surface of any one of claims 22 to 32, wherein the powder particles comprise one or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, fins, ridges, cliffs, pyramids, and inverted pyramids.

34. 34. The surface of any one of claims 22 to 33, wherein the surface lyses one or more cells, and the surface physically or chemically interacts with the cells.

35. 35. A method of rupturing a cell membrane, the method comprising contacting a cell with a surface according to any one of claims 22 to 34, wherein the surface physically or chemically interacts with the cell, thereby rupturing the cell.

36. 35. A method of transferring or replicating a surface structure of an article, the method comprising the step of using a surface according to any one of claims 22 to 34 as a template or mould.

37. Powder particles of a heterofunctional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator, said powder particles comprising two or more types of sub-millimeter structures.

38. Heterofunctional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles, said powder particles comprising sub-millimeter structures and further comprising film coating, plating, chemical functionalization, dopant, nanoparticle decoration, or surface termination.

39. 1. Powder particles of a homofunctional crystalline, polycrystalline, semicrystalline, or amorphous semiconductor or insulator, said powder particles comprising structures selected from pits, craters, cones, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids.

40. 1. Powder particles of a homofunctional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator, said powder particles comprising structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and said powder particles are not elemental silicon, elemental germanium, silicon dioxide, or silicon monoxide particles.

41. 41. Powder particles according to claims 37 to 40, wherein the particles have a diameter of 0.01 to 10,000 microns.

42. 42. The powder particles of claim 41, wherein the particles have a diameter of 0.1 to 1,000 microns.

43. 43. The powder particles of any one of claims 37 to 42, wherein the particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of elements or compounds selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

44. 44. The powder particle of any one of claims 37 to 43, wherein the particle comprises one or more grains.

45. 45. The powder particle of claim 44, wherein the particle consists of a single crystal grain.

46. 46. ​​The powder particles of any one of claims 37 or 41-45, wherein the two or more types of sub-mm structures are selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverted pyramids.

47. 38. The powder particles of claim 37, wherein the two or more types of structures are selected from microstructures and nanostructures.

48. 48. Powder particles according to any one of claims 37 to 47, wherein the particles reflect up to 10% of all electromagnetic radiation with wavelengths between 10 nm and 1 mm.

49. 49. The powder particle of claim 48, wherein the particle reflects up to 10% of total electromagnetic radiation with wavelengths between 10 nm and 400 nm.

50. 49. The powder particle of claim 48, wherein the particle reflects up to 10% of total electromagnetic radiation with wavelengths between 300 nm and 1,000 nm.

51. 49. The powder particle of claim 48, wherein the particle reflects up to 10% of total electromagnetic radiation with wavelengths between 380 nm and 740 nm.

52. 49. The powder particle of claim 48, wherein the particle reflects up to 10% of total electromagnetic radiation with wavelengths between 700 nm and 1 mm.

53. 49. The powder particle of any one of claims 37 to 48, wherein the particle comprises two or more overlapping structures.

54. 54. Powder particles according to any one of claims 37 to 53, wherein the particles are of regular or irregular shape.

55. 55. The powder particle of any one of claims 37 to 54, wherein the particle further comprises a film coating, chemical functionalization, dopant, nanoparticle decoration, or surface termination.

56. 56. The powder particle of any one of claims 37 to 55, wherein the particle is antireflective, reflective, adsorptive, conductive, insulating, antistatic, luminescent, antibacterial, non-wetting, hydrophobic, hydrophilic, antifouling, abrasive, anti-adherent, or a combination thereof.

57. 57. The powder particles of any one of claims 37 to 56, wherein the particles exhibit antibacterial properties.

58. 58. The powder particles of any one of claims 37 to 57, wherein the particles lyse one or more cells, the particles physically or chemically interact with cells.

59. 59. A method of rupturing a cell membrane, the method comprising the step of contacting a cell with powder particles according to any one of claims 37 to 58, wherein the powder particles physically or chemically interact with the cell, thereby rupturing the cell.

60. 1. A method of modifying a property of an article, the method comprising incorporating into the article (e.g., a surface and / or a bulk material thereof) powder particles of one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator, the powder particles comprising one or more sub-millimeter structures, and the powder particles having a diameter of 0.01 to 10,000 microns.

61. 61. The method of claim 60, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

62. 62. The method of claim 60 or 61, wherein the powder particles include one or more grains.

63. 63. The method of claim 62, wherein the powder particles consist of single crystal grains.

64. 64. The method of any one of claims 60 to 63, wherein the powder particles have a diameter of 0.1 to 1,000 microns.

65. 65. The method of any one of claims 60 to 64, wherein the powder particles comprise two or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids.

66. 66. The method of any one of claims 60 to 65, wherein the one or more submillimeter structures are selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids.

67. 67. The method of claim 66, wherein the one or more structures are selected from microstructures and nanostructures.

68. 68. The method of any one of claims 60 to 67, wherein the product is selected from office consumables, business machine containers, electronic machine containers, containers, kitchenware, cooking containers, household goods, textiles, hardware, consumer products, vehicles and watercraft, filters, pumps, aquatic devices, surfaces, furniture, fixtures, equipment, building materials, armaments, tools, solar cells, currency, medical tools, medical devices, paper products, manufacturing equipment, food processing equipment, and optical devices.

69. 69. The method of any one of claims 60 to 68, wherein the article comprises rubber, plastic, metal, glass, or ceramic.

70. 70. The method of any one of claims 60 to 69, wherein the modification comprises one or more of: decreasing the visible light absorbance of the product, increasing the visible light absorbance, decreasing the light reflectance, increasing antibacterial properties, increasing mud resistance, increasing hydrophobicity, increasing hydrophilicity, increasing electrical conductivity, increasing electrical resistivity, increasing photoluminescence, increasing surface energy, decreasing surface energy, increasing coefficient of friction, and decreasing coefficient of friction.

71. 71. The method of any one of claims 60 to 70, wherein incorporating comprises coating the product with the powder particles or embedding the powder particles into the product.

72. 72. The method of claim 71, further comprising exposing the article to a process selected from film coating, plating, chemical functionalization, doping, nanoparticle decoration, lithography, and combinations thereof.

73. 1. A method of lysing (e.g., physically and / or non-chemically) a cell (or a population thereof), the method comprising contacting the cell (or a population thereof) with functional (e.g., crystalline, polycrystalline, semi-crystalline, or amorphous) powder particles, wherein the powder particles comprise one or more sub-millimeter structures (e.g., as described in any of the claims herein), and wherein the powder particles have a diameter of 0.01 to 10,000 microns.

74. 74. The method of claim 73, further comprising exposing the one or more functional powder particles to a process selected from film coating, plating, chemical functionalization, doping, nanoparticle decoration, lithography, and combinations thereof (e.g., according to a process described in any one of the claims herein).

75. 75. The method of claim 73 or 74, wherein the functional particles are configured within a surface of the product.

76. 76. The method of any one of claims 73 to 75, wherein the functional particles are not embedded within another material or surface, such as in a loose powder form.

77. 77. The method of any one of claims 73 to 76, wherein the method comprises lysing a population of cells, wherein at least 30% of the cells are lysed (e.g., at least 50% of the cells are lysed).

78. A low-reflective surface (e.g., of an article), the surface comprising one or more functional crystalline, polycrystalline, semi-crystalline, amorphous (e.g., semiconductor or insulator) powder particles (e.g., a surface including one or more particles configured on its surface and / or one or more particles embedded in its surface), where the powder particles (e.g., optionally) comprise one or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and where the powder particles have a diameter of 0.01 to 10,000 microns.

79. 80. The low reflective surface of claim 78, having a reflectivity (e.g., of reflected and / or scattered light) of about 25% or less (e.g., about 15% or less, about 10% or less, etc.) than another comparable surface and lacking one or more powder particles (e.g., at specific wavelengths such as IR, visible and / or UV wavelengths).

80. 80. A low reflective surface according to any one of claims 78 to 79, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% (e.g. less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, less than 0.2%, etc.) (e.g. at particular wavelengths such as IR, visible and / or UV wavelengths).

81. 81. A low reflective surface according to any one of claims 78 to 80, wherein the reflectivity of the surface (for example of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 10 nm and 1 mm.

82. 81. A low reflective surface according to any one of claims 78 to 80, wherein the reflectivity of the surface (for example of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 10 nm and 400 nm.

83. 81. A low reflective surface according to any one of claims 78 to 80, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 300nm and 1000nm.

84. 81. A low reflective surface according to any one of claims 78 to 80, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 380nm and 740nm.

85. 81. A low reflective surface according to any one of claims 78 to 80, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 700nm and 1mm.

86. 86. A low reflective surface according to any one of claims 78 to 85, wherein the surface comprises a (e.g. bulk) material into which powder particles are incorporated, and the material is silicon or silicon monoxide.

87. 87. A low reflection surface according to any one of claims 78 to 86, wherein the powder particles are any particles according to any one of claims 1 to 58.

88. 1. A method of modifying the light reflectance of an article, the method comprising incorporating into the article (e.g., a surface and / or a bulk material thereof) powder particles of one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductors or insulators, the powder particles comprising one or more sub-millimeter structures, and the powder particles having a diameter of 0.01 to 10,000 microns.

89. 90. The method of claim 88, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

90. 90. The method of any one of claims 88 to 89, wherein the one or more submillimeter structures are selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids.

91. 91. The method of any one of claims 88-90, wherein the reflectivity (e.g., of reflected and / or scattered light) is about 25% or less (e.g., about 15% or less, about 10% or less, etc.) than another comparable surface, and wherein one or more powder particles are devoid (e.g., at particular wavelengths such as IR, visible and / or UV wavelengths).

92. 92. The method of any one of claims 88 to 91, wherein the reflectance (e.g. of reflected and / or scattered light) of the surface is less than 5% (e.g., less than 4%, less than 3%, less than 2%, less than 1%, less than 0.5%, less than 0.2%, etc.) (e.g. at a particular wavelength such as IR, visible and / or UV wavelengths).

93. 93. A method according to any one of claims 89 to 92, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 10 nm and 1 mm.

94. 93. A method according to any one of claims 89 to 92, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 10 nm and 400 nm.

95. 93. A method according to any one of claims 89 to 92, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 300 nm and 1000 nm.

96. 93. A method according to any one of claims 89 to 92, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 380 nm and 740 nm.

97. 93. A method according to any one of claims 89 to 92, wherein the reflectivity of the surface (e.g. of reflected and / or scattered light) is less than 5% for all electromagnetic radiation with wavelengths between 700 nm and 1 mm.

98. 1. A fade resistant pigment (or a product including the pigment incorporated therein or on its surface), the pigment comprising functional crystalline, polycrystalline, semi-crystalline, amorphous (e.g., semiconductor or insulator) powder particles, where the powder particles (e.g., optionally) comprise one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and where the powder particles have a diameter of 0.01 to 10,000 microns.

99. 99. The fade resistant pigment of claim 98, wherein the powder particles are any particles of any one of claims 1 to 58.

100. 1. A method of forming a fade resistant product, the method comprising incorporating into the product (e.g., its surface or the bulk of the material) one or more light exposure fade resistant functional crystalline, polycrystalline, semi-crystalline, amorphous (e.g., semiconductor or insulator) powder particles, wherein the powder particles comprise one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverted pyramids, and wherein the powder particles have a diameter of 0.01 to 10,000 microns.

101. 101. The method of claim 100, wherein the powder particles are any one of the particles from claim 1.

102. A functionalized crystalline, polycrystalline, semi-crystalline, or amorphous (e.g., semiconductor or insulator) particle, the particle comprising (e.g., on its surface) one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and the powder particle diameter is 0.01 to 10,000 microns, and wherein at least a portion of the particle crystal lattice is modified relative to an otherwise equivalent particle that is not functionalized with one or more structures.

103. 103. The powder particle of claim 102, wherein at least a portion of the particle crystal lattice is isotopically expanded and / or contracted.

104. 103. The powder particle of claim 102, wherein at least a portion of the particle crystal lattice is anisotropically expanded and / or contracted.

105. 105. The powder particle of claim 102 or 104, wherein the particle crystal lattice is anisotropically expanded and / or contracted by at least 0.1% along the <111> and / or <311> crystallographic directions relative to an otherwise equivalent particle that is not functionalized with one or more structures.

106. 106. The powder particle of any one of claims 102 to 105, wherein the band structure is modified for at least a portion of the particle relative to an otherwise equivalent particle that is not functionalized with one or more structures.

107. 1. A method of modifying the band structure of at least a portion of a particle, the process comprising providing a surface of the particle (e.g. on its surface) with one or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids and inverted pyramids (e.g. according to a process of any one of the preceding claims), wherein the powder particles have a diameter of 0.01 to 10,000 microns, and wherein at least a portion of the particle crystal lattice is isotopically and / or anisotropically expanded and / or contracted relative to an otherwise equivalent particle not functionalized with the one or more structures.

108. 108. The method of claim 107, wherein the particle crystal lattice is anisotropically expanded and / or contracted by at least 0.1% along the <111> and / or <311> crystallographic directions relative to an otherwise equivalent particle that is not functionalized with one or more structures.

109. 10. A kit (e.g., for lysing one or more cells within a chamber thereof), the kit comprising a container and one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of a semiconductor or insulator, where the powder particles (e.g., optionally) comprise one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, where the powder particles have a diameter of 0.01-10,000 μm, and the container comprises a chamber, and where the one or more functional particles are configured within the chamber.

110. 1. A vessel (e.g., for lysis of one or more cells within its chamber), the vessel comprising a chamber, the chamber comprising an interior surface, the vessel comprising powder particles of one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductors or insulators in (embedded in) or on its interior surface, where the powder particles (e.g., optionally) comprise one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, and where the powder particles have a diameter of 0.01 to 10,000 μm.

111. 111. The kit or container of claim 109 or 110, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

112. 112. The kit or container of any one of claims 109 to 111, wherein the particles further comprise a film coating, chemical functionalization, dopant, nanoparticle decoration or surface termination.

113. 113. The kit or container of any one of claims 109 to 112, wherein the functional particles are configured on a surface of the container.

114. 114. The kit or container of any one of claims 109-113, wherein the functional particles are not embedded within another material or surface, such as in a loose powder form.

115. 115. The kit or container of any one of claims 109 to 114, wherein the functional particles mechanically bond, chemically bond, interact or react with elements, compounds, molecules and particles.

116. 116. The kit or container of any one of claims 109 to 115, wherein the functional particles extract contaminants from a liquid or gas, catalyze or enhance a chemical reaction, lyse cells, remove microorganisms from a liquid or gas, or any combination thereof.

117. A bulk composite (e.g., an article of manufacture) comprising one or more functional crystalline, polycrystalline, semi-crystalline, or amorphous semiconductor or insulator powder particles (e.g., the bulk comprises one or more of the particles configured below its surface), where the powder particles optionally comprise one or more structures selected from pores, pits, craters, nanowires, cones, pinnacles, pillars, corals, cords, walls, fins, ridges, cliffs, pyramids, and inverted pyramids, where the powder particles have a diameter of 0.01 to 10,000 μm.

118. 118. The bulk composite of claim 117, wherein the crystalline, polycrystalline, semi-crystalline, or amorphous powder particles are crystalline, polycrystalline, semi-crystalline, or amorphous powder particles of an element or compound selected from Group IVA elements, Group IV-VI compounds, Group II-IVB compounds, Group I-VII compounds, Group II-VI compounds, Group III-V compounds, Group IV-IV compounds, transition metal oxides, and compounds containing three or more elements.

119. 119. The bulk composite of claim 117 or 118, wherein the powder particles include one or more grains.

120. 120. The bulk composite of claim 119, wherein the powder particles consist of single crystal grains.

121. 121. The bulk composite of any one of claims 117 to 120, wherein the powder particles have a diameter of 0.1 to 1,000 μm.

122. 122. The bulk composite of any one of claims 117 to 121, wherein the powder particles comprise two or more structures selected from pores, depressions, craters, nanowires, cones, pinnacles, pillars, corals, fins, ridges, cliffs, pyramids, and inverted pyramids.

123. 123. The bulk composite of any one of claims 117 to 122, wherein one or more particle structures are sub-millimeter structures.

124. The bulk composite of claim 123, wherein the one or more particle structures are selected from microstructures and nanostructures.

125. 125. The bulk composite of any one of claims 117 to 124, wherein the average diameter of the smallest 30% of the powder particles is 200% smaller than the average diameter of the largest 10% of the powder particles.

126. 126. The bulk composite of any one of claims 117 to 125, wherein the surface is antireflective, reflective, adsorptive, conductive, insulating, antistatic, luminescent, antibacterial, non-wettable, hydrophobic, hydrophilic, antifouling, anti-adherent, anti-slip, or any combination thereof.

127. 127. The bulk composite of any one of claims 117 to 126, wherein the bulk is antistatic, light absorbing, light reflective, antibacterial, conductive, insulating, electrically resistive, photoluminescent, or any combination thereof.

128. 128. The bulk composite of any one of claims 117 to 127, wherein at least a portion of the bulk material is removed exposing at least a portion of the one or more functionalized particles.

Images