Nanoporous membrane

Abstract

A method of making a nanoporous membrane is constructed using an array of sacrificial nanopillars that print removable material on a substrate. After continuous deposition or even of covering layers with different properties, the sacrificial nanostructure is dissolved, and finally the nanoporous membrane with nanopores, channels and cavities designed with nanoscale sizes and geometrical shapes is formed. Thus, unprecedented unique functions are achieved in various technical fields (e.g., bioartificial organs, nanoelectronics, bioelectronics, molecular sensors and biomedical applications).

Description

TECHNICAL BACKGROUND TECHNICAL FIELD

[0001] The disclosed technology relates to the fabrication of nanoporous membranes using sacrificial nanopillars of removable material. BACKGROUND

[0002] Nanoporous membranes are becoming key components in a multitude of different fields, from more traditional electronics, biomedical and chemical applications (e.g. electrochemical storage devices, seawater desalination and chemical separations) to more frontier areas (e.g. bioartificial organs, tissue engineering and nanophotonics).

[0003] Passive nanoporous membranes can separate or filter nanosized entities from a mixture, regardless of their material nature (organic, inorganic or biological). Such nanoporous membranes have become important elements in a multitude of applications, however, if the nanoporous membrane has components that can be subjected to an external stimulus or excitation through them, it becomes an active membrane that provides tunable and controllable properties and enables more complex applications.

[0004] Nanoporous membranes are typically fabricated by a multitude of techniques. Microfabrication (e.g. CNC machining, turning, milling, micro-EDM) is a traditional machining technique, but can only achieve feature sizes and resolutions in the micrometer (pm) or sub-micrometer (pm) scale. Moreover, the materials suitable for such machining are limited to metals and ceramics.

[0005] Chemical etching methods such as ion track etching, anodization and, more recently, controlled break down etching can only generate nanopores with a relatively broad size distribution. Moreover, the generated nanopores are randomly distributed within the membrane. Active components like electrodes or on-chip circuitry cannot be pre-designed and finally fabricated. On the other hand, many chemically etched nanoporous membranes have a polymer as a base material. As a heterogeneous element, e.g. metal electrodes can hardly be included. For the purpose of this disclosure, heterogeneous means that the materials are physically different in their entirety. Therefore, they are typically used as passive membranes. Additional physical inputs such as electric potential, heat and light are difficult to incorporate easily, thus cannot generate additional and desirable interactions with the surrounding environment, in turn, cannot broaden their functionality and range of applications.

[0006] Conventional photolithography and nanoscale fabrication techniques (e.g. atomic layer deposition, scanning force lithography, nanoimprint, dip-pen nanolithography) can generate nanoscale patterns and nanocavities, which are an alternative way to prepare nanoporous membranes, but are typically suitable for the fabrication of thin film structures. High aspect ratio nanoscale features such as vials, channels, reservoirs and compartments cannot be easily prepared. Moreover, the corresponding processes are typically complex, expensive, laborious and, in some cases, very difficult to scale up.

[0007] Thanks to the rapid development of nanoscience and nanotechnology over the past decade, nanoparticles, nanotubes, nanowires, and other nanostructures can now be used to form nanoporous membranes. However, these methods for forming nanoporous membranes are not easy to implement. Furthermore, because the equipment and nanomaterials involved are typically uniquely designed and manufactured at the laboratory level, they are difficult to replicate on a large scale, making production extremely challenging, if not impossible.

[0008] Globally, approximately 2.6 million patients receive kidney replacement therapy through dialysis or kidney transplantation, and this number is projected to double by 2030 (International Society of Nephrology, Global Kidney Health Atlas, https: / / www.theisn.org / initiatives / globalkidney health atlas, updated 2019; accessed February 4, 2022). Given this demand, bio-artificial kidneys have become one of the most popular technologies in medical science since Willem Kolff invented the first dialysis machine in 1943. In particular, wearable and implantable bioartificial kidneys promise to provide continuous dialysis around the clock (Hamid Rabb, Kyungho Lee, and Chirag R. Parikh, Beyond kidney dialysis and transplantation: what's on the horizon?, The Journal of Clinical Investigation, 2022 13(7): e159308). In this regard, nanoporous membranes are one of the key components of wearable and implantable bioartificial kidneys.

[0009] Lithium (Li) is a key material in Li-based devices and components, such as batteries and capacitors. Major Li reserves are estimated to exceed 250 billion tons (Xin Zhang, Aiguo Han, and Yongan Yang, Review on the production of highpurity lithium metal, Journal of Materials Chemistry A, 2020, 8, 22455-22466), of which 230 billion tons are found in the ocean, with the remainder in ores or continental brine. Due to the increasing popularity and widespread application of Li-based devices, the demand for Li is growing rapidly. Following the extraction and exploitation of natural resources, the recycling of Li from electronic waste has become a very important source of Li.

[0010] Here, a novel method for preparing active nanoporous membranes and the resulting products are disclosed. Summary of the Invention

[0011] Nanoporous membranes are fabricated by printing nanopillars of removable material onto a substrate, depositing at least one capping layer, and removing the nanopillars. The nanopillar material may contain removable material, which can be removed by one or more of solvent, heating, chemical, and physical treatments.

[0012] In one configuration, nanopillars are printed or deposited, for example, using 3D printing, nanoimprinting, dip pen lithography, laser writing, or another suitable printing technique. The material is printed or deposited, as exemplified, with an aspect ratio of 3 to 100. Attached Figure Description

[0013] The following description will be further understood when read in conjunction with the accompanying drawings. Exemplary embodiments of the disclosed technology are shown in the drawings for illustrative purposes. This disclosure is not limited to the specific methods, compositions, and apparatuses disclosed. Furthermore, the drawings are not necessarily drawn to scale.

[0014] Figure 1 This is a schematic diagram illustrating the basic manufacturing process of the disclosed technology.

[0015] Figure 2 This is a scanning electron microscope (SEM) image showing photoresist nanopillars fabricated by 3D printing.

[0016] Figure 3 This is a schematic diagram illustrating the manufacturing process of a nanoporous membrane with a modified inner wall surface.

[0017] Figure 4 This is a schematic diagram illustrating a typical capacitor deionization device for metal ion recycling.

[0018] Figure 5 This is a schematic diagram illustrating the fabrication of a nanoporous membrane prepared using the disclosed lithium recycling technology.

[0019] Figure 6 This is a schematic diagram showing a stack of electrode / separator / electrode nanoporous membranes for lithium recycling. Detailed Implementation

[0020] Overview The disclosed technology aims to address the problems and challenges associated with the fabrication of functional nanoporous membranes. The spirit and essence of the disclosed technology are illustrated in the following detailed description with reference to the accompanying drawings. The illustrative embodiments and examples in the specification, drawings, and claims are not intended to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit of the subject matter presented herein.

[0021] The disclosed technology relates to a method for manufacturing nanoporous membranes and related applications. An array of sacrificial nanopillars and / or other nanostructures of removable material is printed on a substrate. After successive deposition of capping layers, even of different properties (organic, inorganic, and biomaterials), the sacrificial nanostructures are dissolved, ultimately forming a nanoporous membrane with nanopores, channels, and cavities designed with nanoscale dimensions and geometries. This enables specific and unique functions to be achieved in various technological fields, such as bioartificial organs, nanoelectronics, bioelectronics, molecular sensors, and biomedical applications.

[0022] The disclosed technology implements a method for manufacturing a nanoporous membrane, in which nanopillars of removable material are printed on a substrate, followed by the deposition of one or more capping layers, and then the nanopillars are removed to prepare a nanoporous membrane. The substrate can be made of metals, non-metals, organic materials, inorganic materials, and biological materials, or combinations thereof.

[0023] In one configuration, the material printed as nanopillars is a removable material. The nanopillar layer can be removed by solvents, by heating, chemical treatment, physical treatment, or a combination of these techniques. The capping layer deposited onto the substrate containing the nanopillars can be a metal, non-metal, organic, inorganic, or biomaterial, or a combination of these materials. The capping layer can be deposited by spin coating, chemical deposition, and physical deposition.

[0024] Nanopillars can be printed or deposited using 3D printing, nanoimprinting, dip pen lithography, laser writing, and any printing technology. The printing technology used can be any technology capable of printing high aspect ratio nanopillars, and can have a high aspect ratio ranging from 3 to 100.

[0025] In another configuration, the preferred diameter of the nanopillars can range from 1 nm to 1000 nm, and the preferred height can range from 100 nm to 10000 nm. The nanopillars can be configured in a cylindrical or conical shape.

[0026] This technique can be used to prepare surfaces that functionalize the inner walls of nanocavities in nanoporous membranes by fabricating nanopillars on a substrate and exposing them to a solution containing self-assembling molecules. One end of the self-assembling molecule can be attached with chemical functional groups that can self-assemble onto the nanopillar surface, imparting desired surface properties. The other end is attached with chemical functional groups that can self-assemble onto the surface of a capping layer exposed during nanopillar removal. One or more capping layers can then be deposited, and the nanopillars removed to prepare a nanoporous membrane with functionalized inner wall surfaces.

[0027] One end of the self-assembled molecule is attached with a chemical group that imparts the desired surface properties and can be bonded to the nanopillar surface through weak chemical and / or physical interactions (e.g., but not limited to electrostatic interactions, ionic bonds, weak chemical bonds). These interactions between the self-assembled molecule and the nanopillar surface can be disrupted through chemical and / or physical treatments. The terminal chemical group attached to the nanopillar surface and / or its adjacent chemical functional groups possess the desired surface and chemical properties of the final inner wall of the pore. The other end of the self-assembled molecule, suspended on the surface of the nanopillar and possessing another chemical functional group, can be strongly bonded to the material of the capping layer to be deposited.

[0028] In another configuration, surface functionalization of the inner walls of the nanocavities of a nanoporous membrane is performed by fabricating nanopillars on a substrate. A precursor solution or material to be printed or deposited onto the substrate as nanopillars is mixed with self-assembly molecules before printing or deposition onto the substrate surface. One end of the self-assembly molecule is attached with a chemical functional group that can strongly bind to the capping material to be deposited and can firmly attach to the capping material on the inner surface of the pores during nanopillar removal, thus preparing a nanoporous membrane with functionalized surfaces on the inner walls. The other end of the self-assembly molecule is attached with a chemical functional group that imparts desired surface properties and remains suspended on the inner wall surface of the pores after nanopillar removal, thereby preparing a nanoporous membrane. One or more capping layers are then deposited and the nanopillars are removed to prepare a nanoporous membrane with functionalized surfaces on the inner walls.

[0029] Nanoporous membranes can be used to manufacture wearable and implantable bioartificial kidneys, which have a multilayer structure consisting of one or more functional covering layers.

[0030] Nanoporous membranes can be used to provide one or more layers functionalized for different purposes, such as, but not limited to, drug delivery, antibacterial, antimicrobial or conductive functions.

[0031] In another configuration, nanoporous membranes can be used for lithium recovery, employing a multilayer structure consisting of one or more functional capping layers. One or more layers are functionalized and / or fabricated for lithium intercalation, lithium adsorption, lithium absorption, lithiation, and / or delithiation. One or more layers are functionalized and / or fabricated as electrodes through which a positive or negative potential can be applied. One or more layers are functionalized and / or fabricated for the intercalation, adsorption, or absorption of other metals or metal ions.

[0032] Basic manufacturing processes Figure 1 This is a schematic diagram illustrating the basic manufacturing process of the disclosed technology. A removable or soluble layer 101 is coated on a support substrate 100. On top of this, nanoscale cylindrical or conical pillars 102 can be fabricated using 3D printing or photolithography, with gaps and cavities formed between the pillars. Compared to photolithography, 3D printing has advantages in the disclosed technology due to its ease of operation and lower operating costs. This technology also offers greater freedom and flexibility in designing nanoscale features. Advantageously, 3D printing can achieve nanoscale structures with high aspect ratios, which is difficult to achieve with conventional photolithography. It should be noted that this does not mean that the fabrication method of the removable layer 101 is limited to 3D printing. The choice of fabrication method does not affect the legitimacy of the disclosed technology.

[0033] The substrate 100 primarily serves as a support. It can be a metal, ceramic, polymer, or any material with sufficient mechanical strength and stiffness to support the nanostructures and corresponding fabrications to be manufactured on it, and possess sufficient chemical inertness to the chemicals involved in subsequent processes. Although it serves as a support, the substrate 100 can be made of solid or porous materials. In the latter case, it can be nanoscale porous and function as a filter itself.

[0034] Advantageously, layer 101 can be made of a soluble material that can be removed by solvents, heating, or other suitable treatments. For example, it could be polymethyl methacrylate (PMMA), which can be removed by acetone. For a portion of layer 101, heating or UV curing may be required to obtain nanopillar strength sufficient to withstand subsequent processes. This layer 101 is optional. It primarily serves as a sacrificial intermediate layer, facilitating the final separation of the nanoporous membrane.

[0035] Subsequently, capping layers of material can be deposited one after another as a multilayer 103 stack. The stack can include capping layers with different material properties or functions, provided that these materials do not react with each other. Therefore, thin-film devices can be constructed around printed or deposited nanopillars.

[0036] The next step is to remove layers 101 and 102. Depending on the material properties, this will be done by solvent removal, wet chemical etching, heating, or other appropriate treatments. This will preserve the material of multilayer 103. Multilayer 103 is a layer with nanopores, the size and morphology of which are determined by the size and morphology of the nanopillars 104.

[0037] Following this final processing, the size of the 3D-printed nanopillars will determine the size and shape of the nanocavities to be constructed. For example, if a 100 nm wide circular nanopillar is 3D printed, a cylindrical nanochannel with a diameter of approximately 100 nm will be formed in the nanoporous membrane. Therefore, the size of the desired nanocavities in the nanoporous membrane offers extremely high controllability and manufacturing flexibility. To date, advanced commercial 3D printers have achieved linewidths of 50 nm (https: / / phenix81.com / plus / view.php?aid=26).

[0038] Figure 2 This is a scanning electron microscope (SEM) image showing photoresist nanopillars fabricated by 3D printing. The SEM shows an example of a 3x3 array of photoresist nanopillars 3D printed on a silicon substrate. The array has three rows of nanopillars with three diameters: 1125 nm, 750 nm, and 500 nm. All nanopillars have a height of 2 μm.

[0039] On the other hand, these nanocavities will be surrounded by stacked capping layers that can be pre-designed to function as active components, such as electrodes, antennas, thermal circuits, etc.

[0040] Surface modification In addition to the exposed nanocavities, the disclosed technology also reveals two methods for surface modification of the inner walls of these nanocavities. This structure has practical value because it can alter the surface properties of the inner walls of the nanocavities. Figure 3 This is a schematic diagram illustrating the manufacturing process of a nanoporous membrane with a modified inner wall surface.

[0041] Layers 300 and 301 are equivalent to Figure 1Molecules 303, 304, and 305 are self-assembled molecules whose chemical functional groups (represented by circles) can impart specific surface properties, such as hydrophilicity, hydrophobicity, and charge. At the other end of the molecule are chemical functional groups (represented by triangles, squares, and hexagons), which undergo specific reactions with specific layers within the stack of capping layers. Although three capping layers (308, 309, and 310) are shown in the illustration, there is no limit to the number of capping layers, as long as their total thickness does not exceed the height of the printed nanopillar.

[0042] Method A The first method disclosed is to first achieve the printing of nanopillars on a substrate as described above, wherein 300, 301, and 302 correspond to Figure 1 Numbers 100, 101, and 102 in the original text are still referenced. Figure 3 These nanopillars are exposed to a solution containing self-assembling molecules 303, 304, and 305, which randomly self-assemble onto the surface of nanopillar 302 as a stack 306, such as... Figure 3 As shown at point A. For illustrative purposes, the specific arrangement of the laminate 306 is given as a non-limiting example, since the order of self-assembly can vary or can be random. In this particular method, chemical functional groups that impart the desired surface properties are required ( Figure 3 The circles in the image will self-assemble onto the surface of the nanopillars. The functional groups at the other end (…) Figure 3 Triangles, squares, and hexagons (from the model) self-assemble onto a specific capping layer exposed within the nanocavity. These specific self-assembled molecules interact specifically with the nanocavity through this capping layer. The bonding between self-assembled molecules can occur through electrostatic interactions, chemical conjugation, or bioconjugation. Ultimately, this results in the formation of chemical functional groups (composed of...) that provide the desired surface properties. Figure 3 (The circles in the image represent) the modified inner nanocavity walls.

[0043] Method B Still refer to Figure 3 The second method disclosed for surface modification of the inner wall of the nanocavity is limited to the removal of printed nanopillars by solvent dissolution or other wet chemical methods. First, suitable self-assembling molecules 303, 304, and 305 are mixed with the "ink" to be printed onto the substrate to form a nanopillar composed of this mixture 307. The nanopillar is then printed onto the substrate, such as... Figure 3As shown in Figure B, after the printed nanopillars are removed by solvent dissolution or other wet chemical methods, these self-assembled molecules are released. Each of these self-assembled molecules can then freely attach to the surface of a specific overlay exposed within the nanocavity, where it interacts specifically. The bonding between the self-assembled molecules can occur through electrostatic interactions, chemical conjugation, or bioconjugation. Ultimately, this results in the formation of chemical functional groups that provide the desired surface properties (composed of…). Figure 3 (The circles in the image represent) the modified inner nanocavity walls.

[0044] If appropriate self-assembling molecules are selected, selective modification of the inner walls of nanocavities can be achieved, such as... Figure 4 As shown at point C.

[0045] Example 1: Membranes for wearable and implantable bioartificial kidneys Silicon (Si) nanoporous membranes are primarily used for this purpose, enabling glomerular filtration. The durability and clotting properties of the blood filter in this bioartificial kidney are critical issues, where the material properties (e.g., biocompatibility, flexibility, anticoagulant activity, etc.) and configuration (e.g., pore size and distribution) of the nanoporous membrane play a crucial role. This disclosure provides a versatile and flexible method for preparing such nanoporous membranes.

[0046] Based on this disclosure, desired nanopores or nanochannels can be constructed first by 3D printing nanopillars of desired size and geometry to effectively filter harmful substances from blood. By using the disclosed technique, selective filtration of single or multiple entities is simple and straightforward because the size and geometry of the fabricated nanopores or nanochannels can be precisely controlled.

[0047] Biocompatible polymers with target physicochemical properties, such as wettability, stiffness, and chemical inertness, can be deposited or spin-coated onto a substrate containing nanopillars. Furthermore, if specific surface properties are desired, the nanocavities to be formed can be surface-modified; for example, by using appropriate chemical reagents with methods A or B described above, better blood compatibility (in terms of surface coagulation, protein adhesion, etc.) can be obtained. Finally, after removing the printed nanopillars, a free-standing nanoporous membrane with uniform and well-controlled pore size and surface properties can be prepared.

[0048] Example 2: Nanoporous membranes for lithium recovery Capacitive deionization (CDI) is a method for recycling Li. Figure 4This is a schematic diagram illustrating a typical capacitive deionization (CDI) device for metal ion recycling. One type of CDI device consists of a porous membrane 400 sandwiched between a pair of porous membrane electrodes 401 and 402, such as... Figure 5 As shown. The diaphragm 400 is used to facilitate fluid flow and electrically isolate the two electrodes 401 and 402. When a specific voltage is applied to the electrodes, it is found that Li recovery via this electroadsorption process is more efficient and more selective in recovering Li from multi-component aqueous solutions (Dong Hee Lee, Taegong Ryu, Junho Shin, Jae Chun Ryu, Kang-Sup Chung and Young Ho Kim, Selective lithium recovery from aqueous solution using a modified membrane capacitive deionization system, 2017, 173, 283-288).

[0049] By using the disclosed technology, porous electrodes / diaphragms / electrode films with highly controllable porosity and pore size can be prepared and used as CDI devices for Li recycling. Figure 1 This is a schematic diagram illustrating the fabrication of a nanoporous membrane prepared using the disclosed lithium recycling technology. First, as described above, 3D printing will produce nanopillars 502 of desired dimensions that determine the size of the nanocavities in the final product, where 500 and 501 correspond to... Figure 6 In the diagram, layers 100 and 101 are deposited sequentially. Then, metal layer 503, insulating layer 504, and another metal layer 505 are deposited as the bottom electrode, separator, and top electrode to form a CDI device. To improve Li-ion selectivity and capacity, additional or more layers of Li-selective materials can be added within the layered structure, for example, on top of the top electrode 505 or below the bottom electrode. These materials can store Li-ions through Faraday reactions, pseudocapacitance, intercalation, or insertion into the bulk. Manganese oxide (MnO2) and iron phosphate (FePO4) are two examples of these Li-selective materials (M. Pasta, CD. Wessels, Y. Cui, F. La Manita, “A desalination battery,” Nano Letters 2012, 12, 839-843). Finally, all nanopillars 502 and layers 501 are removed, ultimately forming a self-supporting nanoporous membrane with a unique sandwich structure of electrode / diaphragm / electrode.

[0050] ​ This is a schematic diagram illustrating a laminate of electrode / separator / electrode nanoporous membrane for lithium recycling. The sandwich membrane can be assembled into a laminate 606 for handling large volumes of waste feed for Li recycling. Porosity and pore size can also be tuned to optimize performance and selectivity.

[0051] Conclusion The description and examples herein are intended as non-limiting examples to illustrate the disclosed techniques and can be modified by those skilled in the art to which the claimed invention pertains within the scope of the subject matter of the claimed invention. On the other hand, this disclosure is not limited to the examples disclosed in the specification of the subject matter application, and the scope of this disclosure should be interpreted based on the claims and includes all techniques within the equivalent scope.

[0052] Based on the foregoing, it should be understood that various embodiments of this disclosure have been described herein for illustrative purposes. This disclosure is not necessarily limited to the specific embodiments disclosed, but rather various substitutions, modifications, and variations can be made to this disclosure and its uses without departing from the spirit and scope thereof. Therefore, the various embodiments disclosed herein are not intended to be restrictive, and the true scope and spirit are indicated by the appended claims.

Claims

1. A method for manufacturing a nanoporous membrane, comprising: Printing nanopillars of removable materials on a substrate; Perform deposition of at least one capping layer; as well as The nanopillars are removed to prepare the nanoporous membrane.

2. The method according to claim 1, wherein, The material printed as nanopillars includes a removable material that can be removed by one or more of solvent, heating, chemical treatment, and physical treatment.

3. The method according to claim 1, further comprising: The nanopillars can be printed or deposited using 3D printing, nanoimprinting, dip pen lithography, laser writing, and any printing technology capable of printing with aspect ratios from 3 to 100.

4. The method according to claim 1, wherein, The nanopillars have diameters ranging from 1 nm to 1000 nm and heights ranging from 100 nm to 10000 nm.

5. The method according to claim 1, wherein, The nanopillars are at least one of cylindrical, conical, and spherical shapes.

6. The method according to claim 1, further comprising: The capping layer is deposited by one of spin coating, chemical deposition, and physical deposition.

7. The method according to claim 1, wherein, The substrate comprises a metal or a combination of a metal and another material.

8. The method according to claim 1, wherein, The substrate comprises a nonmetal or a combination of a nonmetal and another material.

9. The method according to claim 1, wherein, The substrate comprises an organic material and another material.

10. The method according to claim 1, wherein, The capping layer deposited on the substrate comprises a metal or a combination of a metal and another material.

11. The method according to claim 1, wherein, The capping layer deposited on the substrate comprises a nonmetal or a combination of a nonmetal and another material.

12. The method according to claim 1, wherein, The capping layer deposited on the substrate comprises an organic material or an organic material and another material.

13. The method according to claim 1, wherein, The capping layer deposited on the substrate comprises an organic material or an organic material and another material.

14. A method for surface functionalizing the inner wall of a nanocavity in a nanoporous membrane, comprising: The nanopillars are prepared on a substrate using the method for manufacturing nanoporous membranes according to claim 1. as well as Prior to the deposition of at least one capping layer, the nanopillars on the substrate are exposed to a solution containing self-assembling molecules, one end of which is attached to chemical functional groups that impart desired surface properties and self-assemble onto the surface of the nanopillars, and the other end of which is attached to chemical functional groups that self-assemble onto the surface of the capping layer exposed during nanopillar removal. The step of removing the nanopillars involves preparing a nanoporous membrane with a nanocavity inner wall modified by the chemical functional groups.

15. The method according to claim 14, wherein, One end of the self-assembled molecule is attached with a chemical group, which imparts surface properties and binds to the surface of the nanopillar through chemical and / or physical interactions between the self-assembled molecule and the surface of the nanopillar. These chemical and / or physical interactions are disrupted by chemical and / or physical treatment.

16. A method for surface functionalizing the inner wall of a nanocavity in a nanoporous membrane, comprising: Nanopillars are prepared on a substrate using the method for manufacturing a nanoporous membrane according to claim 1. A precursor solution or material, to be printed or deposited onto the substrate as nanopillars, is mixed with self-assembly molecules before printing or depositing onto the surface of the substrate. One end of the self-assembly molecules is attached with chemical functional groups that bind to the material of the capping layer to be deposited and attach to the capping layer material on the inner surface of the pores during nanopillar removal, to prepare the nanoporous membrane having a functionalized surface on the inner wall. The other end of the self-assembly molecules is attached with chemical functional groups that, after nanopillar removal, impart predetermined surface properties to the inner wall surface of the pores to prepare the nanoporous membrane. A step of removing nanopillars is performed to prepare a nanoporous membrane with a functionalized surface on the inner wall.

17. A nanoporous membrane for wearable and implantable bioartificial kidneys, comprising: A multilayer structure consisting of one or more functional overlays manufactured using the method of claim 1.

18. A nanoporous membrane for lithium recovery, comprising: A multilayer structure consisting of one or more functional overlays manufactured using the method of claim 1.

19. The nanoporous membrane according to claim 18, wherein, One or more layers provide at least one lithium interaction selected from the group consisting of lithium intercalation, lithium adsorption, lithium absorption, lithiation, and delithiation.

20. The design according to claim 18, wherein, One or more layers are used as electrodes through which a positive or negative potential can be applied.

21. The design according to claim 18, wherein, One or more layers are used to provide for the intercalation, adsorption, or absorption of other metals or other metal ions.

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