Light-driven coating deposition methods and uses thereof

Abstract

Light-driven deposition methods to form coatings or films, and uses thereof, are described herein. Such coatings or films can be used for various applications, such as in membranes for gas or ion separation.

Description

[0001] LIGHT-DRIVEN COATING DEPOSITION METHODS

[0002] AND USES THEREOF

[0003] CROSS-REFERENCED TO RELATED APPLICATIONS

[0004] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 648,374, filed May 16, 2024, which is hereby incorporated herein by reference in its entirety.

[0005] FIELD OF THE INVENTION

[0006] This invention is in the field of deposition methods to provide coatings or films on substrate surface(s) in a selective and controlled manner.

[0007] BACKGROUND OF THE INVENTION

[0008] Chemical Vapor Deposition (CVD) and Atomic Layer Deposition (ALD) are two widely used techniques in thin film deposition for various applications. While both methods involve depositing thin films onto substrates, they operate on different principles.

[0009] In CVD, precursor gases are introduced into a reaction chamber where they react to form a coating on a substrate surface. The precursor gases undergo chemical reactions, either thermally or through plasma activation, resulting in the deposition of solid material onto the substrate.

[0010] However, CVD often requires high temperatures and / or vacuum conditions, which can limit its compatibility with temperature-sensitive substrates and materials. Moreover, precursor gas chemistry and reaction kinetics can be complex, leading to challenges in controlling film uniformity, composition, and thickness. CVD can also suffer from poor step coverage in complex geometries, resulting in uneven film thickness or void formation.

[0011] In ALD a cyclic deposition process is carried out that alternates between exposing the substrate to precursor gases, followed by purging with inert gas to remove excess reactants. Each cycle deposits a monolayer of material onto the substrate surface, allowing more precise control over film thickness and composition. This results in ALD typically having slower deposition rates, as compared to CVD, which can be a limitation for high-throughput manufacturing applications. ALD may require multiple cycles to achieve a desired film thickness, leading to longer processing times and increased costs. It may also be the case that some precursor materials used in ALD can be expensive or hazardous, and compatibility with specific substrates and deposition conditions may vary. Moreover, such deposition processes are carried out using conventional tools which can also require surface temperatures at >200°C to achieve deposition. Accordingly, certain compositions may not be possible otherwise by, e.g., CVD, ALD, or other known bulk ceramics synthesis methods.

[0012] Thus, there exists a need for developing methods which address and overcome the limitations of currently used film / coating deposition processes.

[0013] Therefore, it is an object of the invention to provide deposition methods which can address and overcome the limitations of currently used film / coating deposition processes.

[0014] Therefore, it is also an object of the invention to provide uses for coatings and films formed according to such deposition methods.

[0015] Therefore, it is a further object of the invention to utilize such methods to control or modify the properties of deposited coatings or films.

[0016] SUMMARY OF THE INVENTION

[0017] Various methods for depositing films or coatings using light whereby high energy photons can initiate coating or thin-fdm deposition are described herein. In one non-limiting instance, a method for depositing a coating (or film) on a substrate, the method includes the steps of:

[0018] (i) placing the substrate into a reactor;

[0019] (ii) sealing and purging the reactor with one or more inert gases;

[0020] (iii) flowing one or more vapor precursors (such as metal-organic vapor precursors), one or more co-reactants, and one or more carrier gases into the reactor;

[0021] (iv) exposing the substrate to one or more wavelengths of light in an effective amount to generate a reactive surface on at least a portion of a surface of the substrate that causes one or more co-reactants to decompose and produce reactive species on the at least a portion of a surface of the substrate; and

[0022] (v) depositing the coating onto the at least a portion of the surface of the substrate, wherein the reactive species reacting with the one or more (metal-organic) precursors causes the coating to deposit onto the at least a portion of the surface of the substrate.

[0023] In some instances, the light absorbed by the deposited coating induces a continual deposition of the coating or film onto the already deposited coating.

[0024] In some instances, the coating deposited is a ceramic coating. In some other instances, the coating deposited is an oxide coating. In still other instances, the coating deposited is a nitride coating. In yet other instances, the coating deposited is a carbide coating. In some other instances, the coating deposited is a boride coating. In still other instances, the coating deposited is a metal oxynitride coating. It is understood that the method can provide for one or more coatings or films on the substrate of any one of the above or combinations thereof. The coating or film deposited can be compositionally uniform throughout the coating or film or can be compositionally graded, wherein the coating comprises different compositions when at least two or more different locations of the coating are compared.

[0025] In certain instances of the methods described, the methods described may be carried out using a reactor (or system thereof) including: at least one gas inlet; at least one gas outlet; a holder for a substrate; a light source which can selectively provide the light onto at least a portion of a surface of the substrate in an effective amount to cause decomposition of one or more co-reactants to produce reactive radical species on the at least a portion of the surface of the substrate; and wherein the reactor comprises an optical window over the holder which permits the light from the light source to reach the at least a portion of a surface of the substrate.

[0026] The various coatings or films which can be produced using the methods described can be used in various applications, such as for membranes with size selective permeance, ion selectivity, preferential adsorption, and as impermeable protective layers (i.e., barriers). Other uses are possible.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Non-limiting embodiments are described by way of example with reference to the accompanying Figures, which are schematic and are not necessarily drawn to scale. In the Figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component shown where illustration is not necessary to allow those of ordinary skill in the art to understand the Figure(s).

[0029] Figure 1 shows a non- limiting representation of a light driven method of depositing a titanium oxide coating on a substrate surface using hydrogen peroxide and titanium isopropoxide vapor reactants.

[0030] Figure 2A shows a non-limiting representation of a reactor 100 which can be used for light-driven vapor deposition of coatings or films on a substrate. The reactor includes an optical window 1 10, a gas inlet 120, a gas outlet 130, and shows a substrate 140 under the optical window.

[0031] Figure 2B shows a non-limiting representation of a reactor 100’ which can be used for light-driven vapor deposition of coatings or films on a substrate. The reactor includes an optical window 110’, first and second gas inlets 120a’ & 120b’, a gas outlet 130’, and shows a substrate 140’ under the optical window.

[0032] Figure 3 shows a non-limiting flow chart for an artificial intelligence (Al) driven study of processing, structure, and property design for coatings or films, which may be used as membranes, made using a light-driven vapor deposition method.

[0033] DETAILED DESCRIPTION OF THE INVENTION

[0034] The present disclosure generally relates to vapor deposition methods that can selectively and controllably provide coatings or films on substrate surface(s) using a light-driven process. Methods of using such coatings or films are also described.

[0035] I. Definitions

[0036] The term “reactive species”, as used herein, refers to one or more species which can be generated in the vapor or gas phase which are reactive and used in the formation of a coating or film. The term “reactive species” includes reactive radical species and reactive oxygen radical species. The reactive species disclosed herein may be gaseous at room temperature and atmospheric pressure.

[0037] “Conformality”, as used herein, refers to the degree of uniformity in the thickness of a coating or film deposited on a surface based on macroscale and / or microscale measurements. Conformality is high, for example, when a deposited coating or film has a uniform thickness over the coated substrate surface.

[0038] “Gaseous or vapor precursors”, as used herein, refers to molecules which can be generated in the gas or vapor phase and can be used to form a coating or film.

[0039] “Gaseous or vapor co-reactants”, as used herein, refers to compounds that are able to reactive species which are used to form a coating or film.

[0040] “Inert gas” or “Carrier gas,” refer to a gas or mixture of gases which are not reactive under reaction conditions within a reactor chamber.

[0041] Numerical ranges disclosed in the present application include, but are not limited to, ranges of temperatures, ranges of pressures, ranges of molecular weights, ranges of integers, ranges of force values, ranges of times, ranges of thicknesses, and ranges of gas flow rates. The disclosed ranges of any type, disclose individually each possible number that such a range could reasonably encompass, as well as any sub-ranges and combinations of sub-ranges encompassed therein. For example, disclosure of a temperature range, is intended to disclose individually every possible temperature value that such a range could encompass, consistent with the disclosure herein. In another example, the disclosure states that light can be emitted in a range from about 700 to about 750 nm, which also refers to light selected independently from about 707, 719, or 749.2 nm, as well as any sub-range between these numbers (for example, about 712 to 743 nm), and any possible combination of ranges between these values.

[0042] Use of the term "about" is intended to describe values either above or below the stated value, which the term “about” modifies, to be within a range of approximately + / - 10%. When the term "about" is used before a range of numbers (i.e., about 1-5) or before a series of numbers (i.e., about 1, 2, 3, 4, etc.) it is intended to modify both ends of the range of numbers and / or each of the numbers recited in the entire series, unless specified otherwise.

[0043] IL Light-Driven Coating Vapor Deposition Methods

[0044] Described herein are light-driven methods for depositing films or coatings, such as high entropy coatings, using light whereby high energy photons can initiate coating or thin-film deposition where the deposition process is preferably limited to substrate surfaces. In other words, the deposition process of the methods described can occur via localized reactions on the surface of the substrate. As discussed in detail below, the methods described can be used to deposit, for example, oxides and can also be extended to deposit nitrides, carbides, borides, and their ternary and quaternary alloys. The coatings can be selectively deposited on various substrate surfaces including those made of, without limitation, glass, ceramic, semiconductor(s), and metal(s), particularly at room temperature, whereas conventional deposition tools require surface temperatures at >200°C to achieve deposition.

[0045] In one non-limiting instance, a method for depositing a coating (or film) on a substrate, the method includes the steps of:

[0046] (i) placing the substrate into a reactor;

[0047] (ii) sealing and purging the reactor with one or more inert gases;

[0048] (iii) flowing one or more vapor precursors (such as metal-organic vapor precursors), one or more co-reactants, and one or more carrier gases into the reactor;

[0049] (iv) exposing the substrate to one or more wavelengths of light in an effective amount to generate a reactive surface on at least a portion of a surface of the substrate that causes one or more co-reactants to decompose and produce reactive species on the at least a portion of a surface of the substrate; and (v) depositing the coating onto the at least a portion of the surface of the substrate, wherein the reactive species reacting with the one or more (metal-organic) precursors causes the coating to deposit onto the at least a portion of the surface of the substrate.

[0050] A non-limiting representation of the above method is shown in Figure 1. The methods described herein rely on a light-driven process whereby an effective amount of light forms a reactive surface, when the light hits the substrate surface(s) onto which it is exposed, and causes one or more co-reactants to decompose and produce reactive species on the at least a portion of a surface of the substrate which react with the precursors resulting in deposition of a coating or film onto the surface. The reactive surface is essentially or entirely confined to where the light hits the surface(s) of the substrate and defines the area(s) of the surface(s) where deposition proceeds. In some instances, the method does not include heating the substrate or the at least a portion of the surface of the substrate on which the coating is formed.

[0051] The reactor typically includes a gas handling system which allows for introductions and provides independent pressure control for all the gases or vapors introduced into the reactor, such as the inert gas(es), vapor precursor(s), co-reactant(s), and carrier gas(es), as may be present. Such gas handling and pressure control systems are known to the skilled person. Exemplary non- limiting reactors, which may be used for the methods disclosed, are described below and shown in Figures 2 A and 2B.

[0052] In some instances, the sealing step is carried out at an effective pressure of the one or more inert gases to remove or minimize the amount of ambient atmosphere present in the reactor when the substrate is placed into the reactor in step (i). The effective pressure can be in a range of about 25 to 150 kPa, as well as individual values or subranges within the aforementioned range. The purging of the reactor with the one or more inert gases (such as selected from argon, nitrogen, helium, and combinations thereof) can be used to remove or minimize the amount of ambient atmosphere present in the reactor when the substrate is placed into the reactor in step (i). In certain instances, step (ii) may include optionally pumping the reactor under a vacuum and then purging with the one or more inert gases; optionally with two or more pumping -purging cycles performed.

[0053] In some instances, the light absorbed by the deposited coating induces a continual deposition of the coating during step (v). This is understood to occur while the light is continued to be exposed onto the formed or forming coating or film. In other words, once the coating or film grows on the surface, the light absorbed in the skin-depth of the as-deposited coating makes the vapor precursors continuously deposit resulting in continual deposition. In some instances, the method, or steps of the method, can he carried out at ambient temperature in a range from about 25 to 50, about 15 to 50, or about 5 to 50 degrees Celsius, as well as individual temperatures or sub-ranges within the aforementioned ranges.

[0054] In some instances, the deposition time ranges from about 5 minutes to 120 hours, as well as individual temperatures or sub-ranges within the aforementioned ranges.

[0055] In some instances, the coating deposited is a ceramic coating. In some other instances, the coating deposited is an oxide coating. In still other instances, the coating deposited is a nitride coating. In yet other instances, the coating deposited is a carbide coating. In some other instances, the coating deposited is a boride coating. In still other instances, the coating deposited is a metal oxynitride coating. It is understood that the method can provide for one or more coatings or films on the substrate of any one of the above or combinations thereof. By selecting the appropriate conditions, it is possible to deposit a desired coating or film. As desired, the method may include repeating steps (iii)-(v) wherein the composition of vapor precursors, coreactants, and carrier gases can be varied to change to a different coating or film type or a different relative composition of the same coating or film previously deposited. In making such changes, the method may include a step of purging the reactor with one or more inert gases to remove the preceding vapor precursors and co-reactants from the reactor prior to the next coating or film being deposited. In other words, steps (iii), (iv), and (v) may be repeated at least once optionally changing at least one of the one or more (metal-organic) vapor precursors, the one or more co-reactants, and / or the one or more carrier gases between each repetition. The method is also understood to be useful for batch deposition of coatings or films.

[0056] In some instances of the methods, the coating deposited includes a ternary or quaternary metal oxide; or the coating deposited includes a ternary or quaternary alloy of oxides, nitrides, carbides, and / or borides. In some instances, the coating deposited is a titanium oxide coating, where the titanium oxide can be a ternary titanium oxide (such as (Ti,Al)Oxwhere 1 < x < 2; (Ti,V)Oxwhere 1 < x < 2.5; or TiOxNywhere 0 < x < 2, 0 < y < 1.5). In other instances, the coating deposited is a vanadium oxide coating (i.e., VOXwhere 1 < x < 2; or VxOywhere 1 < x < 2, 1 < y < 5).

[0057] In certain other instances, the coating deposited can be compositionally uniform throughout the coating or film. In other words, the coating or film has the same or substantially the same composition across the entire coating or film. “Substantially the same,” refers to a difference of less than about 5%, 4%, 3%, 2%, or 1 % of the relative composition between any two different locations evaluated by a suitable technique known in the art (such as those named above). As described below, the composition may also be graded. In some instances, the substrate is a glass substrate, ceramic substrate, a semiconductor substrate, an oxide-containing substrate, a metal substrate, a porous or nanoporous substrate, or a polymer support substrate (which may be porous or nanoporous). In some instances, the average pore diameter in a porous or nanoporous substrate is in a range from about 2 angstroms to 10 nm, as well as individual values or sub-ranges contained therein. In certain instances, the substrate includes or is made of SrTiCh, SnCh. and Bi VO4 In still other instances, the substrates can be selected from fluorine-doped tin oxide, titanium oxide particle films, and / or bismuth vanadium films. In some instances, the substrate is non-planar. The shape and size of the substrate is not particularly restricted. In some instances, the method provides coatings or films that are conformal on the non-planar aspects of the substrate. In some instances, the substrate is a porous polymer support substrate which in combination with the polymer coating deposited thereon forms a porous membrane, which can be used, for instance, for selective for gas separation or selective ion separation.

[0058] In certain instances, the substrate may undergo one or more preparation steps prior to deposition of the coating thereon. Several possible preparation steps are possible. For example, in some instances, the substrate or reactor may be cleaned by exposing the substrate or reactor to a fluid and then soaking the substrate or reactor in the fluid, rinsing the substrate or reactor with the fluid, and / or sonicating the substrate or reactor in the presence of the fluid prior to the reaction. Non-limiting examples of suitable fluids for such processes include organic solvents, water, and / or solutions comprising an organic or aqueous solvent and a surfactant. In some instances, the substrate may be exposed to an elevated temperature and / or a reduced pressure in order to remove volatile contaminants. Suitable temperatures include temperatures between 20 °C and 300 °C. Suitable pressures include pressures between 0.1 mTorr and 1 atm. According to certain instances, the substrate may undergo a plasma cleaning step prior to the deposition. Other preparation steps are also possible.

[0059] In some instances, the reactive species is a reactive radical species. In some particular instances, the reactive species is a reactive oxygen radical species. Such reactive species may be generated from known compounds, which can be considered co-reactants in the methods. In some instances, the one or more co-reactants are selected from a peroxide (such as hydrogen peroxide), oxygen, ozone, water (or water vapor), methanol, ethylene, acetylene, ammonia, and combinations thereof. In some instances, water vapor is present as a co-reactant to react with the one or more (metal-organic) vapor precursors at the light-activated reactive surface.

[0060] In some instances, the one or more (metal-organic) vapor precursors, without limitation, can be selected from titanium isopropoxide, vanadium isopropoxide, hafnium isopropoxide, zirconium isopropoxide, aluminum isopropoxide, niobium isopropoxide, tantalum isopropoxide, and combinations thereof.

[0061] The one or more carrier gases can be selected, without particular limitation, from argon, nitrogen, helium, hydrogen, carbon dioxide, and combinations thereof.

[0062] In some instances, the one or more wavelengths of the light are in the ultraviolet range of the light spectrum, such as from about 100 nm to 400 nm, as well as individual values or subranges within the aforementioned range. In some instances, the one or more wavelengths of light are in the blue range of the light spectrum, such as from about 450 to 495 nm, as well as individual values or sub-ranges within the aforementioned range. In some instances, a 55 mW blue LED light (435 nm) can be used.

[0063] The coating can be selectively deposited only on the at least a portion of the surface of the substrate exposed to the one or more wavelengths of the light. In other words, little to no deposition of coating or film occurs where the light is not exposed onto. “Little,” refers to the amount of coating or film which may be present on the substrate where the light was not exposed is reduced by at least 95%, 96%, 97%, 98%, 99%, or more of the amount deposited where the light was exposed. Such selectivity can be used to provide patterning of the coatings or films deposited. For example, a photomask can be used to provide patterns of the light on the substrate and used to form such patterned films or coatings only where the light passes through the mask. The patterns are not particularly restricted. Suitable photomasks and materials to prepare these in a suitable pattern are known in the art. In some instances, the pattern can be a striped or striated pattern. Patterning can be achieved by laser scribing over an optical mask. Patterning can also be dynamic by generating from optical lithography in real-time.

[0064] The thickness of the coating or film formed by the method is not particularly restricted. In some instances, the coating or film is a thin-film coating having a thickness ranging from about 1 to 5000, 50 to 5000, 500 to 5000, 500 to 2500, 50 to 1000, or 500 to 1000 nm, as well as individual values or subranges contained within any of the aforementioned ranges. In some instances, the coating or film is a conformal coating. In some instances, the coating deposited is mechanically compliant, where “mechanically compliant,” refers to the coating / film having the ability to deform or accommodate mechanical stress(es) and strain(s) without experiencing significant damage or failure.

[0065] In certain other instances, the coatings formed by the methods described herein have an average thickness of greater than or equal to 25 nm, greater than or equal to 50 nm, greater than or equal to 75 nm, greater than or equal to 100 nm, greater than or equal to 250 nm, greater than or equal to 500 nm, greater than or equal to 750 nm, greater than or equal to 1 pm, greater than or equal to 2.5 u m, greater than or equal to 5 um, greater than or equal to 7.5 pm, greater than or equal to 10 pm, greater than or equal to 25 pm, or greater than or equal to 50 pm. In certain instances, polymeric coatings may have an average thickness of less than or equal to 100 pm, less than or equal to 50 pm, less than or equal to 25 pm, less than or equal to 10 pm, less than or equal to 7.5 pm, less than or equal to 5 pm, less than or equal to 2.5 pm, less than or equal to 1 pm, less than or equal to 750 nm, less than or equal to 500 nm, less than or equal to 250 nm, less than or equal to 100 nm, less than or equal to 75 nm, or less than or equal to 50 nm. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 50 nm and less than or equal to 10 pm, greater than or equal to 100 nm and less than or equal to 10 um, or greater than or equal to 100 nm and less than or equal to 1 um). One of ordinary skill in the art would be aware of methods for determining the thickness of polymeric coatings.

[0066] In certain instances of the methods, the coating deposition proceeds at any suitable deposition rate. In certain instances, the deposition rate of the coating or film is in a range of about 0.1 to 0.5 microns / min, as well as individual values or subranges contained within. In some instances, the deposition rate may be greater than or equal to 1 nm / min, greater than or equal to 2.5 nm / min, greater than or equal to 5 nm / min, greater than or equal to 10 nm / min, greater than or equal to 25 nm / min, greater than or equal to 50 nm / min, greater than or equal to 75 nm / min, or greater than or equal to 100 nm / min. In certain instances, the deposition rate may be less than or equal to 100 nm / min, less than or equal to 75 nm / min, less than or equal to 50 nm / min, less than or equal to 25 nm / min, less than or equal to 10 nm / min, less than or equal to 5 nm / min, less than or equal to 2.5 nm / min, less than or equal to 1 nm / min, Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 50 nm / min and less than or equal to 10 nm / min). In some instances, a typical coating or film deposition or growth rate is about 1 to 5 micrometers per hour, as well as individual values or sub-ranges within the aforementioned range; or about 2 micrometers per hour.

[0067] According to some embodiments, the coating or film may be formed on at least a portion of one or more surfaces exposed to the light. In some instances, the coating or film is formed on substantially all of or all of the surface(s) exposed to the light, where “substantially all” encompasses or covers substantially all of the surface(s) intended to be coated (e.g., greater than about 99%, about 99.5%, about 99.8%, about 99.9%, about 99.99%, or 100% of the surface(s) to be coated.

[0068] In some instances, the light delivered to the substrate surface has an intensity in a range of about 10 to 100 mW, 25 to 100 mW, or 50 to 100 mW, as well as individual values or subranges disclosed within the aforementioned ranges. In certain instances, the one or more surfaces of the substrate(s), or of the reactor, can he treated prior to the first step with a treatment which is selected from electron beam, IR radiation, gamma radiation, plasma exposure, thermal treatment, laser exposure, or a combination thereof. In certain instances, following formation / deposition of the coating or film, a treatment may be applied to the coating, such as an annealing treatment, or application of an electron beam, IR radiation, gamma radiation, plasma exposure, thermal treatment, laser exposure, or a combination thereof. a. Parameters of Precursors, Co-Reactants, and Carrier Gases

[0069] For the methods described herein, the coating or film may be formed under any suitable total pressure in the reactor. As noted, the reactor can include systems and components for controlling and regulating the desired partial and total pressures of each of the aforementioned vapors / gases used in the methods. In some instances, the total pressure of all gaseous components during the flowing step ranges from about 50 to 200 kPa, as well as individual values or sub-ranges contained within the aforementioned range.

[0070] Deposition of the coating or film occurs under conditions including the presence of one or more precursors, one or more co-reactants, and one or more carrier gases which may be each be independently present at any suitable partial pressure. The partial pressures of the aforementioned are typically such that the sum of the partial pressures is within the range of about 50 to 200 kPa, as well as individual values or sub-ranges contained within the aforementioned range.

[0071] The one or more precursors and one or more co-reactants may be provided in any suitable ratio. In some instances, the ratio may be based on the partial pressures of the one or more precursors to the one or more co-reactants present during the methods described. The ratio of the partial pressure of the one or more precursors to the partial pressure of the one or more coreactants, is defined as the partial pressure of the one or more precursors divided by the partial pressure of the one or more co-reactants present, may be any suitable value. In certain instances, the ratio may be greater than or equal to 0. 1 , greater than or equal to 0.2, greater than or equal to 0.5, greater than or equal to 0.8, greater than or equal to 1, greater than or equal to 2, greater than or equal to 5, or greater than or equal to 10. In some instances, the ratio may be less than or equal to 10, less than or equal to 8, less than or equal to 5, less than or equal to 2, less than or equal to 1, less than or equal to 0.8, less than or equal to 0.5, or less than or equal to 0.2. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 0.1 and less than or equal to 10). In some instances (e.g., during the deposition of a coating or film), a reactor may include a relatively high amount of precursor(s). In some instances, precursors make up greater than or equal to 1 mol%, greater than or equal to 2 mol%, greater than or equal to 5 mol%, greater than or equal to 7.5 mol%, greater than or equal to 10 mol%, greater than or equal to 15 mol%, greater than or equal to 20 mol%, greater than or equal to 30 mol%, greater than or equal to 40 mol%, greater than or equal to 50 mol%, or greater than or equal to 75 mol% of the gases flowed into the reactor’s chamber. In some instances, precursor(s) make up less than or equal to 100 mol%, less than or equal to 75 mol%, less than or equal to 50 mol%, less than or equal to 40 mol%, less than or equal to 30 mol%, less than or equal to 20 mol%, less than or equal to 15 mol%, less than or equal to 10 mol%, less than or equal to 7.5 mol%, less than or equal to 5 mol%, or less than or equal to 2 mol% of the gases flowed into the reactor’s chamber. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 1 mol% and less than or equal to 100 mol%).

[0072] The carrier gases or inert gases may contribute any suitable percentage of the total pressure during deposition. In some instances, the carrier or inert gas(es) comprise greater than or equal to 50% of the total pressure, greater than or equal to 60% of the total pressure, greater than or equal to 70% of the total pressure, greater than or equal to 80% of the total pressure, greater than or equal to 90% of the total pressure, or greater than or equal to 95% of the total pressure. In certain embodiments, the inert gas(es) comprise less than or equal to 98% of the total pressure, less than or equal to 95% of the total pressure, less than or equal to 90% of the total pressure, less than or equal to 80% of the total pressure, less than or equal to 70% of the total pressure, or less than or equal to 60% of the total pressure. Combinations of the above- referenced ranges are also possible (e.g., greater than or equal to 50% of the total pressure and less than or equal to 90% of the total pressure, greater than or equal to 70% of the total pressure and less than or equal to 90% of the total pressure, or greater than or equal to 80% of the total pressure and less than or equal to 90% of the total pressure).

[0073] In some instances, the residence time of a given vapor or gas may be defined as the total amount of time that vapor or gas spends in the reaction chamber prior to either flowing out or undergoing deposition. The residence times for the precursor(s), co-reactant(s), and carrier gas(es) may be each be independently of any suitable value. In some cases, these may independently have a residence time of greater than or equal to 5 seconds, greater than or equal to 10 seconds, greater than or equal to 15 seconds, greater than or equal to 30 seconds, greater than or equal to 45 seconds, greater than or equal to 60 seconds, greater than or equal to 90 seconds, greater than or equal to 120 seconds, or greater than or equal to 180 seconds. In certain instances, each of these can have a residence time of less than or equal to 300 seconds, less than or equal to 180 seconds, less than or equal to 120 seconds, less than or equal to 90 seconds, less than or equal to 60 seconds, less than or equal to 45 seconds, less than or equal to 30 seconds, less than or equal to 15 seconds, or less than or equal to 10 seconds. Combinations of the above- referenced ranges are also possible (e.g., greater than or equal to 15 seconds and less than or equal to 90 seconds). In some embodiments, the residence time of all of the gases or vapors is substantially similar. b. Coatings or Films

[0074] The methods described herein can be used to achieve alloyed compositions far beyond those predicted at phase equilibria, e.g., 45% Mn2+in TiCF host oxide. Thus, the methods allows for the deposition of compositionally graded ternary oxides, thereby building a combinatorial high-throughput synthesis capability. Such complexity can be used to tune the coating or film composition which can affect features of chemical stability, charge transport, and size-selective ion transport, thus deciphering the role of high entropy.

[0075] For instance, the coatings or films formed by the method can be high entropy coatings or films. “High entropy coating or film” as used herein, refers to coatings or films formed from a mixture of multiple elements (such as Ti, Al, O, N, etc.), which may be in equimolar proportions, resulting in a high degree of compositional complexity and disorder. These may be ternary or quaternary coatings or films. The presence of multiple elements, such as in near-equal concentrations, can introduce structural disorder and increase the entropy of the coating or film formed. Such high degree of disorder can lead to several desired properties including: enhanced mechanical properties; improved thermal stability; tailorable properties; and / or multifunctionality. For example, high-entropy ceramic coatings often exhibit superior mechanical properties, including high hardness, strength, and wear resistance. The presence of multiple elements can disrupt the formation of crystal defects and grain boundaries, resulting in improved mechanical performance. In some instances, the compositional complexity of high- entropy ceramic coatings can enhance their thermal stability and resistance to high temperatures. By adjusting the composition and processing parameters, the properties of high-entropy ceramic coatings can be tailored to meet specific application requirements. High-entropy ceramic coatings, for instance, may exhibit multifunctional properties, combining mechanical, thermal, electrical, and optical functionalities within.

[0076] In some instances, the coating deposited is compositionally graded wherein the coating comprises different compositions when at least two or more different locations of the coating are compared. For instance, the composition is determined to be different at least at two different locations of the coating or film. In some instances, the composition changes in a gradient manner between two points within the coating or film, where each location when moving between two points selected may be compositionally different from other locations. The compositions may change in change in various ways, such as by increasing or decreasing in the content of an element present. Moreover, the method can be used to control / tune the composition of the coating or film by varying the composition / ratios of vapor precursor(s) and co-reactant(s), as needed. For instance, the process described can be used to access continuous and tunable coating or film compositions that are not limited by thermodynamic equilibria (X. Shen, et al., ACS Applied Electronic Materials, 2023, 5, 1812-1823; and G. Siddiqi, et al., ACS Appl Mater Inter, 2018, 10, 18805-18815.) Various techniques are known to the skilled person to evaluate the compositional make up of coatings and films, at one or more locations or in its entirety, such as X-ray Photoelectron Spectroscopy (XPS), Energy-dispersive X-ray Spectroscopy (EDS), etc.

[0077] Thus, coatings or films which are compositionally graded can be used to provide one or more differences in chemical stability, charge transport, and / or size-selective ion transport within the coating or film.

[0078] III. Reactor System for Light-Driven Vapor Deposition of Coatings

[0079] In certain instances of the methods described, the methods described may be carried out using a reactor (or system thereof) including: at least one gas inlet; at least one gas outlet; a holder for a substrate; a light source which can selectively provide the light onto at least a portion of a surface of the substrate in an effective amount to cause decomposition of one or more co-reactants to produce reactive radical species on the at least a portion of the surface of the substrate; and wherein the reactor comprises an optical window over the holder which permits the light from the light source to reach the at least a portion of a surface of the substrate.

[0080] In one non-limiting example, as shown in Figure 2A, a non-limiting representation of a reactor 100 includes an optical window 110, a gas inlet 120, a gas outlet 130, and shows a substrate 140 under the optical window.

[0081] In another non-limiting example, as shown in Figure 2B, a non-limiting representation of a reactor 100’ includes an optical window 110’, first and second gas inlets 120a’ & 120b’, a gas outlet 130’, and shows a substrate 140’ under the optical window.

[0082] The optical window may be formed of any suitable material which allows for the light source to pass through the material for exposure onto the desired portion of the substrate, and surface(s) thereof. The material may be made of, for example, glass, quartz, or plastic (which is optically clear) such that all the light or at least about 90%, 95%, 96%, 97%, 98%, 99%, or greater of the light of the appropriate wavelength(s) is transmitted through the optical window onto the substrate.

[0083] In certain instances, the reactor includes a gas handling system to distribute the one or more vapor or gaseous reactants and optional carrier gases introduced through the at least one gas inlet port into the reactor. In some instances, the vapor or gaseous reactants (i.e., precursor(s) and co-reactant(s)) and carrier gas(es) originate from a source which takes the form of a reservoir (such as a vessel) of a material that may be placed in and / or removed from fluidic communication with the reactor by an (inlet / outlet) port. As one example, a source of gas or reactants may take the form of and / or include a gas cylinder (e.g., having pressurized gas therein). The port may separate the reaction volume from the source, and may be opened and / or closed to place the source in and / or out of fluidic communication with the reaction chamber. The port may be in direct or indirect fluidic communication with the source. For instance, the port may be in fluidic communication with the source via tubing.

[0084] In some instances, it is also possible for the reactor to include a source of vacuum. The source of vacuum may be configured to evacuate the reactor chamber when in fluidic communication therewith. A variety of suitable types of sources of vacuum may be employed. As an example, in some instances, a source of vacuum comprises a vacuum pump. The vacuum pump, when turned on and in fluidic communication with the reaction volume, may evacuate the reaction volume by pumping out its contents.

[0085] In some instances, the reactor is a 3-D printed reactor. In some other instances, the reactor is a flat-bed reactor.

[0086] In some instances, the light includes one or more wavelengths in the ultraviolet range of the light spectrum. In other instances, the light includes one or more wavelengths in the blue range of the light spectrum. The light source is not particularly restricted and can be an LED light or thermal light source, such as those known in the art. The light source can be controlled to provide one or more wavelengths of light needed to decompose the co-reactants for film deposition. Moreover, the light source can also include focusing optics to adjust intensity, spot size, and beam convergence or divergence of the light produced. Such focusing optics are known to the skilled person, as well as control of the various parameters.

[0087] IV. Uses of the Coatings formed by Light-Driven Vapor Deposition

[0088] The methods described above can be used to deposit / form coating(s) or film(s) on surface(s) of a substrate. As noted, the coatings or films can be selectively deposited onto one or more surfaces of a substrate via a light-driven process, whereby the coating or film is only deposited where light is exposed onto the selected surface(s), or portions thereof. Further, in some instances, such ambient-temperature coating methods allow for formation of coatings with compositions far-from-equilibrium, not possible otherwise by, e.g., chemical vapor deposition (CVD) and bulk ceramics synthesis. Such deposition is driven by light which allows for broader temperature ranges for substrate heating, potentially mitigating thermal expansion mismatch between coating(s) and the substrate. It is believed without limitation that under illumination, the forming or formed coating surface can produce charges or heat (e.g., localized plasmonic hot spots) to drive surface reactions for deposition. Such methods can also produce conformal coatings with atomic-scale elemental mixing in minutes, whereas conventional deposition tools can take days to complete, if such coatings are even achievable with conventional processing. The various coatings or films which can be produced using the methods described can be used in various applications, such as for membranes with size selective permeance, ion selectivity, preferential adsorption, and as impermeable protective layers (i.e., barriers).

[0089] Due to the tunability of the various parameters of the methods described it is possible to build a combinatorial high-throughput synthesis capability for depositing compositionally complex and graded coatings or films, which can function as membranes, such as by depositing them on a nanoporous polymer support substrate. Such coatings can be grown to provide selective membranes. For example, oxynitrides are known to be chemically stable and mechanically robust, and one can rely on the pH-dependent positive charge of quaternary ammonium groups at inner pores to realize anion selectivity; and vice versa for negative charges of oxide pores for cation selectivity. The method can also be used to form membranes on appropriate support substrates with a capability to control the microstructure and chemical state of membranes, where for example, each location on the formed coating / membrane can have a slightly different composition compared to nearby locations. Such porous (i.e., ceramic) membranes could be used for separations, where selectivity is modulated by pore sizes and preferential interactions with inner pores in a confined space.

[0090] The methods described can be employed for data-driven materials discovery, as compared to conventional approaches which can only afford a few synthesis-characterization- analysis iterations. As illustrated in Figure 3, artificial intelligence (Al) can be used to drive autonomous membrane discovery, by establishing predictive correlations between the membrane processing conditions and the structures and properties of porous membranes needed for desired size- and charge-based separations. With sufficiently labeled training data on the processingstructure relationship, supervised machine learning (ML) models can be built and trained to map processing conditions to provide for coatings or films on substrate structures with desired properties (i.e., chemical stability, charge transport, size-selective ion transport. This provides a basis to develop phenomenological models to screen and achieve one or more desirable property. Moreover, based on the predictions from the supervised ML model, we expect to inversely design membrane properties (blue dash arrow), e.g., pore sizes, charge signs and density of surface charges.

[0091] In some instances, the coatings or films may act as catalytic coatings or films. In other instances, the coatings or films act as membranes and can perform in harsh operational environments, such as: at high temperatures or strong acid and base.; and may also demonstrate resistance against bio-fouling.

[0092] The disclosed methods, coatings, and reactors can be further understood through the following numbered paragraphs.

[0093] Paragraph 1. A method for depositing a coating on a substrate, the method comprising the steps of:

[0094] (i) placing the substrate into a reactor;

[0095] (ii) sealing and purging the reactor with one or more inert gases;

[0096] (iii) flowing one or more vapor precursors, one or more co-reactants, and one or more carrier gases into the reactor;

[0097] (iv) exposing the substrate to one or more wavelengths of light in an effective amount to generate a reactive surface on at least a portion of a surface of the substrate that causes one or more co-reactants to decompose and produce reactive species on the at least a portion of a surface of the substrate; and

[0098] (v) depositing the coating onto the at least a portion of the surface of the substrate, wherein the reactive species reacting with the one or more precursors causes the coating to deposit onto the at least a portion of the surface of the substrate.

[0099] Paragraph 2. The method of paragraph 1 , wherein the reactive species is a reactive radical species.

[0100] Paragraph 3. The method of any one of paragraphs 1-2, wherein the sealing step is carried out at an effective pressure in a range of about 25 to 150 kPa.

[0101] Paragraph 4. The method of any one of paragraphs 1-3, wherein the light absorbed by the deposited coating induces continual deposition of the coating during step (iv).

[0102] Paragraph 5. The method of any one of paragraphs 1 -4, wherein the method is carried out at ambient temperature which is in a range from about 5 to 50 degrees Celsius. Paragraph 6. The method of any one of paragraphs 1 -5, wherein at least steps (iii), (iv), and (v) of the method are carried out at ambient pressure which is in a range of about 70 to 200 kPa.

[0103] Paragraph 7. The method of any one of paragraphs 1-6, wherein the coating deposited is a ceramic coating.

[0104] Paragraph 8. The method of any one of paragraphs 1-6, wherein the coating deposited is an oxide coating.

[0105] Paragraph 9. The method of any one of paragraphs 1-6, wherein the coating deposited is a nitride coating.

[0106] Paragraph 10. The method of any one of paragraphs 1-6, wherein the coating deposited is a carbide coating.

[0107] Paragraph 11. The method of any one of paragraphs 1-6, wherein the coating deposited is a boride coating.

[0108] Paragraph 12. The method of any one of paragraphs 1-6, wherein the coating deposited is a metal oxynitride coating.

[0109] Paragraph 13. The method of any one of paragraphs 1-6, wherein the coating deposited comprises a ternary or quaternary metal oxide; or the coating deposited comprises a ternary or quaternary alloy of oxides, nitrides, carbides, and / or borides.

[0110] Paragraph 14. The method of any one of paragraphs 1-13, wherein the coating deposited is compositionally graded wherein the coating comprises different compositions when at least two or more different locations of the coating are compared.

[0111] Paragraph 15. The method of any one of paragraphs 1-13, wherein the coating deposited is compositionally uniform throughout the coating.

[0112] Paragraph 16. The method of any one of paragraphs 1-15, wherein the substrate is a glass substrate, ceramic substrate, a semiconductor substrate, an oxide-containing substrate, a metal substrate, or a polymer support substrate (which may be porous or nanoporous).

[0113] Paragraph 17. The method of any one of paragraphs 1-16, wherein the substrate is non- planar.

[0114] Paragraph 18. The method of any one of paragraphs 1-17, wherein the reactive species is a reactive oxygen radical species.

[0115] Paragraph 19. The method of any one of paragraphs 1-18, wherein the one or more vapor precursors are selected from the group consisting of titanium isopropoxide, vanadium isopropoxide, hafnium isopropoxide, zirconium isopropoxide, and combinations thereof. Paragraph 20. The method of any one of paragraphs 1 -19, wherein the one or more coreactants are selected from the group consisting of a peroxide (such as hydrogen peroxide), oxygen, ozone, water, methanol, ethylene, acetylene, ammonia, and combinations thereof.

[0116] Paragraph 21. The method of any one of paragraphs 1-20, wherein the one or more carrier gases are selected from the group consisting of argon, nitrogen, helium, hydrogen, and combinations thereof.

[0117] Paragraph 22. The method of any one of paragraphs 1-21, wherein the one or more wavelengths of the light are in the ultraviolet range of the light spectrum.

[0118] Paragraph 23. The method of any one of paragraphs 1-21, wherein the one or more wavelengths of light are in the blue range of the light spectrum.

[0119] Paragraph 24. The method of any one of paragraphs 1-23, wherein the coating is deposited only on the at least a portion of the surface of the substrate exposed to the one or more wavelengths of the light.

[0120] Paragraph 25. The method of any one of paragraphs 1-24, wherein the coating is a thin- film coating having a thickness ranging from about 1 to 5000 nm.

[0121] Paragraph 26. The method of paragraph 25, wherein the coating is a conformal coating.

[0122] Paragraph 27. The method of any one of paragraphs 1-26, wherein the steps (iii), (iv), and (v) are repeated at least once optionally changing at least one of the one or more vapor precursors, the one or more co-reactants, and / or the one or more carrier gases between each repetition.

[0123] Paragraph 28. The method of any one of paragraphs 1-27, wherein the reactor is a 3-D printed reactor.

[0124] Paragraph 29. The method of any one of paragraphs 1-28, wherein the reactor is a flatbed reactor.

[0125] Paragraph 30. The method of any one of paragraphs 1-29, wherein the coating deposited is mechanically compliant.

[0126] Paragraph 31. The method of any one of paragraphs 1 -30, wherein the coating deposited is a titanium oxide coating.

[0127] Paragraph 32. The method of claim 31, wherein the titanium oxide is a ternary titanium oxide (such as (Ti,Al)Oxwhere 1 < x < 2; (Ti,V)Oxwhere 1 < x < 2.5; or TiOxNywhere 0 < x < 2, 0 < y < 1.5).

[0128] Paragraph 33. The method of any one of paragraphs 1 -30, wherein the coating deposited is a vanadium oxide coating. Paragraph 34. A coating on a substrate formed by the method of any one of paragraphs

[0129] 1-33.

[0130] Paragraph 35. The coating of paragraph 34, wherein the coating is a titanium oxide coating.

[0131] Paragraph 36. The coating of paragraph 35, wherein the titanium oxide is a ternary titanium oxide (such as (Ti,Al)Oxwhere 1 < x < 2; (Ti,V)Oxwhere 1 < x < 2.5; or TiOxNywhere 0 < x < 2, 0 < y < 1.5).

[0132] Paragraph 37. The coating of paragraph 34, wherein the coating is a vanadium oxide coating.

[0133] Paragraph 38. The coating of any one of paragraphs 34-37, wherein the substrate is a glass substrate, ceramic substrate, a semiconductor substrate, an oxide-containing substrate, a metal substrate, or a polymer support substrate (which may be porous or nanoporous).

[0134] Paragraph 39. The coating of any one of paragraphs 34-38, wherein the coating is compositionally graded wherein the coating comprises different compositions when at least two or more different locations of the coating are compared; and wherein optionally the compositional grading provides one or more differences in chemical stability, charge transport, and / or size-selective ion transport within the coating.

[0135] Paragraph 40. The coating of paragraph 34, wherein the substrate is a porous polymer support substrate which in combination with the polymer coating deposited thereon forms a porous membrane.

[0136] Paragraph 41. The coating of paragraph 34, wherein the porous membrane is selective for gas separation or is selective for ion separation.

[0137] Paragraph 42. A reactor for depositing a coating on a substrate utilizing light, the reactor comprising: at least one gas inlet; at least one gas outlet; a holder for a substrate; a light source which can selectively provide the light onto at least a portion of a surface of the substrate in an effective amount to cause decomposition of one or more co-reactants to produce reactive radical species on the at least a portion of the surface of the substrate; and wherein the reactor comprises an optical window over the holder which permits the light from the light source to reach the at least a portion of a surface of the substrate. Paragraph 43. The reactor of paragraph 42, wherein the reactor is a 3-D printed reactor.

[0138] Paragraph 44. The reactor of any one of paragraphs 42-43, wherein the reactor is a flatbed reactor.

[0139] Paragraph 45. The reactor of any one of paragraphs 42-44, wherein the light comprises one or more wavelengths in the ultraviolet range of the light spectrum.

[0140] Paragraph 46. The reactor of any one of paragraphs 42-44, wherein the light comprises one or more wavelengths in the blue range of the light spectrum.

[0141] Paragraph 47. The reactor of any one of paragraphs 42-46, wherein the light source is an LED light or thermal light source.

[0142] Paragraph 48. The reactor of any one of paragraphs 42-47, wherein the light source provides a single wavelength or multiple wavelengths.

[0143] Paragraph 49. The reactor of any one of paragraphs 42-48, wherein the light source further comprises focusing optics to adjust intensity, spot size, and beam convergence or divergence of the light.

[0144] Paragraph 50. The reactor of any one of paragraphs 42-49, wherein the reactor further comprises a gas handling system which can regulate the pressure of one or more precursor, coreactant, and carrier gases when delivered to the substrate through the at least one gas inlet.

[0145] EXAMPLE

[0146] Example 1: Titanium Oxide and Vanadium Oxide Coatings formed using a Light- Driven Deposition Process

[0147] Titanium oxide and vanadium oxide were grown in an ambient pressure reactor. Argon gas was purged into the reactor for 5 minutes prior to deposition. The base pressure of the reactor was 101 kPa and the reactor was at room temperature. The light-driven deposition process was based on isopropoxide precursors. For titanium oxide, Ti{OCH (043)2)4 (TTIP) from Sigma Aldrich 99.9% was used. For vanadium oxide, OV(OCH(CH3)z)3 (VTIP, Vanadium(V) oxytriisopropoxide) from Sigma Aldrich 99.9% was used.

[0148] The titanium precursor was filled in a bubbler and placed in an oil bath of 30-75 °C temperatures to obtain a proper vapor pressure. The vanadium precursor was filled in a bubbler and placed in an oil bath of 5-60 °C temperatures to obtain a proper vapor pressure. Carbon dioxide gas flowed into the Ti bubbler to bring the TTIP vapor out. Argon gas flowed into the vanadium bubbler to bring the VTIP vapor out. Argon gas was also used to bring water vapor out of another water bubbler. The metal-organic precursor and water vapor were mixed in a 3D- printed reactor. A quartz window was used to seal the reactor at the ambient pressure (e.g., 101 kPa). A 55 mW blue LED light (435 nm) was illuminated through the quartz window to the surface of the substrate. The substrates used include fluorine-doped tin oxide, titanium oxide particle films, and bismuth vanadium thin films. The deposition time ranges from 5 minutes to 120 hours. A typical growth rate is 2 micrometers per hour.

[0149] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of skill in the art to which the disclosed invention belongs. Publications cited herein and the materials for which they are cited are specifically incorporated by reference. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific instances of the invention described herein. Such equivalents are intended to be encompassed by the following claims.

Claims

CLAIMSI claim:

1. A method for depositing a coating on a substrate, the method comprising the steps of:(i) placing the substrate into a reactor;(ii) sealing and purging the reactor with one or more inert gases;(iii) flowing one or more vapor precursors, one or more co-reactants, and one or more carrier gases into the reactor;(iv) exposing the substrate to one or more wavelengths of light in an effective amount to generate a reactive surface on at least a portion of a surface of the substrate that causes one or more co-reactants to decompose and produce reactive species on the at least a portion of a surface of the substrate; and(v) depositing the coating onto the at least a portion of the surface of the substrate, wherein the reactive species reacting with the one or more precursors causes the coating to deposit onto the at least a portion of the surface of the substrate.

2. The method of claim 1, wherein the reactive species is a reactive radical species.

3. The method of any one of claims 1-2, wherein the sealing step is carried out at an effective pressure in a range of about 25 to 150 kPa.

4. The method of any one of claims 1-2, wherein the light absorbed by the deposited coating induces continual deposition of the coating during step (iv).

5. The method of any one of claims 1-2, wherein the method is carried out at ambient temperature which is in a range from about 5 to 50 degrees Celsius.

6. The method of any one of claims 1-2, wherein at least steps (iii), (iv), and (v) of the method are carried out at ambient pressure which is in a range of about 70 to 200 kPa.

7. The method of any one of claims 1-2, wherein the coating deposited is a ceramic coating.

8. The method of any one of claims 1-2, wherein the coating deposited is an oxide coating.

9. The method of any one of claims 1-2, wherein the coating deposited is a nitride coating.

10. The method of any one of claims 1-2, wherein the coating deposited is a carbide coating.

11. The method of any one of claims 1-2, wherein the coating deposited is a boride coating.

12. The method of any one of claims 1-2, wherein the coating deposited is a metal oxynitride coating.

13. The method of any one of claims 1-2, wherein the coating deposited comprises a ternary or quaternary metal oxide; or the coating deposited comprises a ternary or quaternary alloy of oxides, nitrides, carbides, and / or borides.

14. The method of any one of claims 1-2, wherein the coating deposited is compositionally graded wherein the coating comprises different compositions when at least two or more different locations of the coating are compared.

15. The method of any one of claims 1-2, wherein the coating deposited is compositionally uniform throughout the coating.

16. The method of any one of claims 1-2, wherein the substrate is a glass substrate, ceramic substrate, a semiconductor substrate, an oxide-containing substrate, a metal substrate, or a polymer support substrate (which may be porous or nanoporous).

17. The method of any one of claims 1-2, wherein the substrate is non-planar.

18. The method of any one of claims 1-2, wherein the reactive species is a reactive oxygen radical species.

19. The method of any one of claims 1-2, wherein the one or more vapor precursors are selected from the group consisting of titanium isopropoxide, vanadium isopropoxide, hafnium isopropoxide, zirconium isopropoxide, and combinations thereof.

20. The method of any one of claims 1-2, wherein the one or more co-reactants are selected from the group consisting of a peroxide (such as hydrogen peroxide), oxygen, ozone, water, methanol, ethylene, acetylene, ammonia, and combinations thereof.

21. The method of any one of claims 1-2, wherein the one or more carrier gases are selected from the group consisting of argon, nitrogen, helium, hydrogen, and combinations thereof.

22. The method of any one of claims 1-2, wherein the one or more wavelengths of the light are in the ultraviolet range of the light spectrum.

23. The method of any one of claims 1-2, wherein the one or more wavelengths of light are in the blue range of the light spectrum.

24. The method of any one of claims 1-2, wherein the coating is deposited only on the at least a portion of the surface of the substrate exposed to the one or more wavelengths of the light.

25. The method of any one of claims 1-2, wherein the coating is a thin- film coating having a thickness ranging from about 1 to 5000 nm.

26. The method of claim 25, wherein the coating is a conformal coating.

27. The method of any one of claims 1-2, wherein the steps (iii), (iv), and (v) are repeated at least once optionally changing at least one of the one or more vapor precursors, the one or more coreactants, and / or the one or more carrier gases between each repetition.

28. The method of any one of claims 1-2, wherein the reactor is a 3-D printed reactor.

29. The method of any one of claims 1-2, wherein the reactor is a flat-bed reactor.

30. The method of any one of claims 1-2, wherein the coating deposited is mechanically compliant.

31. The method of any one of claims 1-2, wherein the coating deposited is a titanium oxide coating.

32. The method of claim 31 , wherein the titanium oxide is a ternary titanium oxide (such as (Ti,Al)Oxwhere 1 < x < 2; (Ti,V)Oxwhere 1 < x < 2.5; or TiOxNywhere 0 < x < 2, 0 < y < 1.5).

33. The method of any one of claims 1-2, wherein the coating deposited is a vanadium oxide coating.

34. A coating on a substrate formed by the method of any one of claims 1-2.

35. The coating of claim 34, wherein the coating is a titanium oxide coating.

36. The coating of claim 35, wherein the titanium oxide is a ternary titanium oxide (such as(Ti,Al)Oxwhere 1 < x < 2; (Ti,V)Oxwhere 1 < x < 2.5; or TiOxNywhere 0 < x < 2, 0 < y < 1.5).

37. The coating of claim 34, wherein the coating is a vanadium oxide coating.

38. The coating of any one of claims 34-37, wherein the substrate is a glass substrate, ceramic substrate, a semiconductor substrate, an oxide-containing substrate, a metal substrate, or a polymer support substrate (which may be porous or nanoporous).

39. The coating of any one of claims 34-37, wherein the coating is compositionally graded wherein the coating comprises different compositions when at least two or more different locations of the coating are compared; and wherein optionally the compositional grading provides one or more differences in chemical stability, charge transport, and / or size-selective ion transport within the coating.

40. The coating of claim 34, wherein the substrate is a porous polymer support substrate which in combination with the polymer coating deposited thereon forms a porous membrane.

41. The coating of claim 34, wherein the porous membrane is selective for gas separation or is selective for ion separation.

42. A reactor for depositing a coating on a substrate utilizing light, the reactor comprising: at least one gas inlet; at least one gas outlet; a holder for a substrate; a light source which can selectively provide the light onto at least a portion of a surface of the substrate in an effective amount to cause decomposition of one or more co-reactants to produce reactive radical species on the at least a portion of the surface of the substrate; and wherein the reactor comprises an optical window over the holder which permits the light from the light source to reach the at least a portion of a surface of the substrate.

43. The reactor of claim 42, wherein the reactor is a 3-D printed reactor.

44. The reactor of any one of claims 42-43, wherein the reactor is a flat-bed reactor.

45. The reactor of any one of claims 42-43, wherein the light comprises one or more wavelengths in the ultraviolet range of the light spectrum.

46. The reactor of any one of claims 42-43, wherein the light comprises one or more wavelengths in the blue range of the light spectrum.

47. The reactor of any one of claims 42-43, wherein the light source is an LED light or thermal light source.

48. The reactor of any one of claims 42-43, wherein the light source provides a single wavelength or multiple wavelengths.

49. The reactor of any one of claims 42-43, wherein the light source further comprises focusing optics to adjust intensity, spot size, and beam convergence or divergence of the light.

50. The reactor of any one of claims 42-43, wherein the reactor further comprises a gas handling system which can regulate the pressure of one or more precursor, co-reactant, and carrier gases when delivered to the substrate through the at least one gas inlet.

Images