Ta3n5-based photoelectrode based on magnetron sputtering and preparation method thereof

Abstract

The application relates to photoelectric catalysis technology and aims to provide a Ta3N5-based photoelectrode based on magnetron sputtering and a preparation method. x Si y layer, a Ta3N5 layer and MNPs nano metal particles; the Ti x Si y layer is formed by the reaction of a second Ti metal layer and a SiO2 layer, and the Ta3N5 layer is formed by the reaction of a Ta2O5 layer and NH3; the MNPs metal particles contain Ag or Cu. The application can greatly save the amount of noble metal, reduce the preparation cost and expand the application range; is favorable to improving the transportation of photo-generated carriers, can greatly improve the photoelectric utilization efficiency; and can greatly reduce the energy loss between two photo-thermal application interfaces and improve the photo-thermal utilization efficiency of a single photoelectrode.

Description

Technical Field

[0001] The present invention relates to the technical field of photoelectrocatalysis for utilizing solar energy, and in particular to a Ta3N5-based photoelectrode based on magnetron sputtering and a preparation method thereof. Background Art

[0002] Solar energy is considered a promising energy source due to its widespread availability and clean application environment. Developing devices and systems to convert solar energy into sustainable energy is a highly desirable solution to meeting the growing global energy demand and addressing the environmental problems associated with fossil fuel consumption.

[0003] Photoelectrochemical (PEC) water splitting is considered a promising approach for converting solar energy into renewable, clean hydrogen fuel. Semiconductors that absorb sunlight to generate electron-hole pairs are central to this approach. However, PEC conversion efficiency is severely limited by the oxygen evolution reaction (OER) occurring at the semiconductor anode. Therefore, the rational design and preparation of anodes with high oxygen evolution reaction (OER) conversion efficiency is crucial for realizing future solar energy utilization. Among various semiconductors, tantalum nitride (Ta3N5) is widely considered an attractive anode material due to its suitable solar absorption band gap (2.0-2.1 eV) and high theoretical maximum solar energy conversion efficiency (15.9%). However, the reported PEC water splitting performance of Ta3N5 photoelectrochemical grades is generally far below theoretical expectations, primarily due to its high charge recombination rate, excess surface active sites, and poor surface activity. Recently, various photoelectrochemical anode catalyst modification strategies, including elemental doping, heterojunction construction, and morphology tailoring, have been widely reported, generally aiming to improve the PEC water oxidation activity of Ta3N5 anodes, and significant progress has been made in the past decade. However, these Ta3N5 anodes still suffer from inherent problems such as severe surface charge recombination and poor surface activity, resulting in high onset potentials and poor PEC conversion efficiencies. Furthermore, Ta3N5 anodes disclosed in existing literature typically have limited absorption of the solar spectrum, absorbing only approximately 600nm. This wastes visible infrared light and limits PEC applications.

[0004] Photothermal catalysis (PTC) has attracted much attention because of its full spectrum utilization and the absence of the need for bias voltage. Localized surface plasmon resonance (LSPR) causes metal nanoparticles to strongly absorb the solar spectrum. Therefore, the coupling of photothermal catalysis and photoelectrocatalysis may improve catalytic activity and achieve full spectrum utilization, and is also a focus of researchers. However, the current research direction is mainly focused on the combination of the two electrodes. For example, the Chinese invention patent "Method for preparing hydrocarbons by photoelectric-photothermal coupling using water and CO2 as raw materials" (CN116770331A) integrates the photoelectrocatalytic submodule and the photothermal catalytic submodule in a transparent reactor, and uses the combination of solar photoelectrocatalysis and photothermal catalysis technology to achieve graded and quality-based full spectrum utilization of the solar spectrum. However, such a separate use method can only play a catalytic role of each other. Although they can complement each other, they cannot promote each other. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a Ta3N5-based photoelectrode and a preparation method thereof based on magnetron sputtering. x Si y The film layer bonds the Ta3N5 layer to the Pt / Ti layer and can promote the separation and transmission of photogenerated carriers.

[0006] In order to solve the above technical problems, the solution of the present invention is:

[0007] Provided is a Ta3N5-based photoelectrode based on magnetron sputtering, wherein the Ta3N5-based photoelectrode is based on quartz glass as a substrate and has a multilayer film structure formed on the substrate by magnetron sputtering and after thermal nitriding and coating treatment; the multilayer film structure comprises, from bottom to top, a first Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nano metal particles; the Ti x Si y The layer is a uniform material layer formed by the reaction and combination transformation of the second Ti metal layer and the SiO2 layer, and the Ta3N5 layer is a uniform material layer formed by the reaction and combination transformation of the Ta2O5 layer and NH3; the MNPs metal particles contain Ag or Cu, and M refers to Ag or Cu with photothermal properties.

[0008] As a preferred embodiment of the present invention, the thickness of the first Ti metal layer is in the range of 2 to 50 nm, the thickness of the Pt conductive metal layer is in the range of 100 to 200 nm, and the Ti x Si yThe thickness of the layer ranges from 2 to 50 nm, the thickness of the Ta3N5 layer ranges from 500 to 700 nm; and the thickness of the MNPs nanometal particles ranges from 25 to 100 nm.

[0009] As a preferred embodiment of the present invention, the thickness ratio of the second Ti metal layer to the SiO2 layer is x / y, and its value range is 0.02 to 5.

[0010] The present invention further provides a method for preparing the aforementioned Ta3N5-based photoelectrode based on magnetron sputtering, comprising the following steps:

[0011] (1) Using a quartz glass plate of appropriate size as the substrate, clean it with acetone, anhydrous ethanol, and deionized water in sequence;

[0012] (2) First, a first Ti metal layer and a Pt conductive metal layer are sequentially deposited on the substrate using a magnetron sputtering process; according to the design of the photoelectrode, the area reserved for conduction is partially shielded, and then a second Ti metal layer, a SiO2 layer, and a Ta2O5 layer are sequentially deposited using a magnetron sputtering process;

[0013] (3) The sample that has completed the multilayer deposition process is moved into a horizontal quartz tube furnace for thermal nitriding treatment. During this process, the second Ti metal layer and the SiO2 layer react and combine to form a uniform Ti x Si y layer, the Ta2O5 layer combines with NH3 to transform into a uniform Ta3N5 layer;

[0014] (4) A metal nanoparticle (MNPs) precursor solution was prepared by a reduction method, which was dropped onto the Ta3N5 layer on the sample surface and evenly spread. After drying, it was washed with deionized water to obtain a Ta3N5-based photoelectrode, which was recorded as MNPs@Ta3N5 / Ti x Si y Photoanode.

[0015] As a preferred embodiment of the present invention, during the magnetron sputtering treatment in step (2), the deposition thickness of each layer on the sample is: the first Ti metal layer is 2 to 50 nm, the Pt metal conductive layer is 100 to 200 nm; the second Ti metal layer is 2 to 50 nm, the SiO2 layer is 10 to 100 nm, and the Ta2O5 layer is 500 to 700 nm.

[0016] As a preferred embodiment of the present invention, during the magnetron sputtering process in step (2), Ar gas is introduced into the magnetron sputtering chamber at a rate of 37 sccm, and the minimum vacuum is maintained at 6.7E. -7 MPa.

[0017] As a preferred embodiment of the present invention, during the thermal nitriding treatment in step (3), the sample is heated from room temperature to 940-1000°C at a rate of 5°C / min under normal pressure, kept at this temperature for 5 hours, and then naturally cooled to room temperature; during this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the treatment chamber.

[0018] As a preferred embodiment of the present invention, the concentration of the MNPs precursor solution in step (4) is 0.1 mol / L, and the amount of the solution added is 0.6 to 2.4 mL / cm 2 .

[0019] As a preferred embodiment of the present invention, the drying treatment in step (4) refers to placing the sample on a heating plate at 100° C. for drying for 30 to 60 minutes.

[0020] As a preferred embodiment of the present invention, the coating thickness of the MNPs precursor solution is controlled so that the thickness of the MNPs nanometal particles on the surface of the Ta3N5-based photoelectrode after drying is 25 to 100 nm.

[0021] Description of the invention principle:

[0022] In existing PEC technology, the tantalum nitride (Ta3N5) anode typically needs to be mounted on a precious metal (such as Pt), resulting in high costs and limited widespread application. Furthermore, coupling the Ta3N5 anode with PTC technology is also a challenge.

[0023] The present invention innovatively proposes to combine magnetron sputtering and thermal nitriding technology to realize the conversion of Ti-SiO2 layer into Ti x Si y layer, Ta2O5-NH3 is combined and converted into Ta3N5 layer; thus, Ti x Si y The layer effectively bonds Ta3N5 to precious metals such as Pt, greatly saving the amount of precious metals and creating conditions for expanding the scope of application. In addition, Ti x Si y On the one hand, the Ti layer can utilize UV-visible light to enhance the light and induce the separation and migration of EHPs; on the other hand, x Si y The Fermi levels of Ta3N5 and Ta3N5 are 4.55eV and 4.14eV respectively, and their energy levels are adapted, which is beneficial to improving the transport of photogenerated carriers.

[0024] The present invention further innovatively proposes that, using a photoirradiated MNP precursor solution, monochromatic light can be used to form metal nanoparticles with a specific morphology and specific absorption wavelength. By coating these nanoparticles on the surface of a Ta3N5 film layer to form a metal with photothermal properties (such as Ag and Cu), photothermal-photoelectric coupling is achieved within a single photoelectrode product. This further reduces manufacturing costs, improves photothermal efficiency, and expands its application range.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. Compared with the traditional technology of loading Ta3N5 on a metal substrate, the present invention adopts a specific Ta3N5 / Ti x Si y The multilayer film structure is bonded to a quartz glass substrate, which can significantly save precious metal usage, reduce preparation costs, and expand the scope of application.

[0027] 2. In the multilayer film structure of the product of the present invention, due to the Ti x Si y The layer can enhance the separation and migration of photoinduced EHPs using UV-visible light, and the Ti x Si y Adapting to the Fermi level of Ta3N5 is beneficial to improving the transport of photogenerated carriers; therefore, it can greatly improve the photoelectric utilization efficiency.

[0028] 3. The product of the present invention utilizes a multi-layer film structure to coat nano-metal particles of Ag and Cu with photothermal properties on the surface of the Ta3N5 film layer, abandoning the separate usage method in traditional technology, greatly reducing the energy loss between the two photothermal application interfaces, thereby improving the photothermal utilization efficiency of the single photoelectrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The Ta3N5 / Ti x Si y Schematic diagram of the structure and fabrication process.

[0030] Figure 2 MNPs@Ta3N5 / Ti x Si y SEM images at different magnifications.

[0031] Figure 3 The figure is a comparison of the photocurrent density of the photoelectrode prepared by the present invention and the photoelectrode of the prior art. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with specific embodiments:

[0033] In the present invention, magnetron sputtering and thermal nitridation treatment technologies are both mature processes for semiconductor device processing. The preparation of metal nanoparticle (MNPs) precursor solution is also recorded in many public documents. The present invention does not make special requirements and will not be described in detail.

[0034] Part I: Implementation of the Invention

[0035] 1. Preparation of Ta3N5-based photoelectrode

[0036] (1) Use appropriate size (such as 10×20×1mm 3 ) quartz glass as a substrate, and cleaned with acetone, anhydrous ethanol and deionized water in sequence;

[0037] (2) First, a first Ti metal layer and a Pt conductive metal layer are deposited on the substrate in sequence by magnetron sputtering. According to the design of the photoelectrode, the area reserved for conduction is partially shielded, and then a second Ti metal layer, a SiO2 layer, and a Ta2O5 layer are deposited in sequence by magnetron sputtering. During the magnetron sputtering process, Ar gas is introduced into the magnetron sputtering chamber at a rate of 37 sccm, and the minimum vacuum is maintained at 6.7E. -7 MPa.

[0038] The thicknesses of the deposited layers on the sample are: a first Ti metal layer of 2 to 50 nm, a Pt metal conductive layer of 100 to 200 nm; a second Ti metal layer of 2 to 50 nm, a SiO2 layer of 10 to 100 nm, and a Ta2O5 layer of 500 to 700 nm. The thickness ratio of the second Ti metal layer to the SiO2 layer is x / y, and its value ranges from 0.02 to 5.

[0039] (3) The sample after multilayer deposition was moved into a horizontal quartz tube furnace for thermal nitriding treatment: the temperature was raised from room temperature to 940-1000°C at a rate of 5°C / min under normal pressure, kept at this temperature for 5 hours, and then naturally cooled to room temperature; during this process, flowing ammonia was introduced to maintain an ammonia atmosphere in the treatment chamber. After treatment, the second Ti metal layer was combined with the SiO2 layer to transform into a uniform Ti x Si y layer, and the Ta2O5 layer combines with NH3 to transform into a uniform Ta3N5 layer.

[0040] (4) Metal nanoparticle (MNPs) precursor solutions of Ag and Cu were prepared by reduction method, and the concentration of the MNPs precursor solution was 0.1 mol / L.

[0041] The precursor solution was dropped onto the Ta3N5 layer on the sample surface, with a drop area of ​​10×10 mm 2 , the drop amount is 0.6~2.4mL / cm2 , and spread evenly; the sample was placed on a hot plate at 100 ° C for 30 to 60 minutes; then washed with deionized water to obtain a Ta3N5-based photoelectrode, denoted as MNPs@Ta3N5 / Ti x Si y Photoanode: The coating thickness of the MNPs precursor solution is controlled so that the thickness of the MNPs nanometal particles on the surface of the Ta3N5-based photoelectrode after drying is 25 to 100 nm.

[0042] The Ta3N5-based photoelectrode product is based on quartz glass as a substrate, and has a multilayer film structure formed on the substrate by magnetron sputtering and thermal nitriding and coating treatment; from bottom to top, it includes a Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs layer; M in MNPs nanometal particles refers to Ag and Cu with photothermal properties. x Si y The Ta3N5 layer is a uniform material layer formed by the reaction of the second Ti metal layer and the SiO2 layer, and the Ta3N5 layer is a uniform material layer formed by the reaction of the Ta2O5 layer and the N2 layer.

[0043] As an optional example, the thickness of the Ti metal layer is in the range of 2 to 50 nm, the thickness of the Pt conductive metal layer is in the range of 100 to 200 nm, and the thickness of the Ti x Si y The thickness of the Ta3N5 layer ranges from 2 to 50 nm, and the thickness of the Ta3N5 layer ranges from 500 to 700 nm.

[0044] 2. Examples of how to use Ta3N5-based photoelectrode products

[0045] The following is an example of how to use the photoelectrode product: Use Nafion 117 membrane to separate the Pt cathode chamber and the photoanode chamber, use the photoelectrode as the working electrode, the platinum sheet as the counter electrode, and a calomel reference electrode, and connect to an electrochemical workstation. Use an AM 1.5G filter to simulate standard sunlight, with an intensity calibrated to 100mW·cm -2 Photoelectrochemical measurements of the photoelectrochemical level were performed under simulated sunlight.

[0046] Part II Examples and Comparative Examples

[0047] Example 1

[0048] According to the general formula Ti x Si y , where x / y = 0.02 to prepare AgNPs@Ta3N5 / Ti x Si y .

[0049] The size is 10×20×1mm 3 A quartz glass substrate was used and cleaned sequentially with acetone, anhydrous ethanol, and deionized water. A 2 nm thick Ti layer was deposited on the quartz substrate by sputtering, followed by a 100 nm thick Pt layer. The sample was partially masked to expose an area of ​​10 × 10 mm. 2 Then, a Ti layer with a thickness of 2 nm, a SiO2 layer with a thickness of 100 nm, and a Ta2O5 layer with a thickness of 500 nm were deposited in sequence by sputtering. During the magnetron sputtering process, Ar gas was introduced into the chamber at a rate of 37 sccm, and the minimum vacuum degree was maintained at 5.0E. -6 Torr (i.e. 6.7E -7 MPa). Ta3N5 / Ti was obtained by thermal nitriding Ta2O5 / SiO2 / Ti / Pt / Ti thin films in a horizontal quartz tube furnace, heating from room temperature to 1000℃ at a rate of 5℃ / min under ambient pressure, holding for 5 hours, and naturally cooling to room temperature. x Si y During this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the processing chamber.

[0050] Prepare a precursor solution containing 88mL of high-purity water, 1mL of 0.01M AgNO3, and 10mL of 0.01M sodium citrate. Stir at 1200r / min for 20 minutes, then slowly add 0.8mL of 0.01M NaBH4 and stir for 30 seconds. After stirring, the precursor solution was irradiated with 550nm monochromatic light in a 40℃ water bath for 14 hours to obtain a AgNPs solution with a concentration of 0.1mol / L. Add 0.6mL of the AgNPs solution to the exposed area of ​​the sample (10×10mm 2 ) and spread evenly; the sample was placed on a hot plate at 100 ° C for 60 minutes. Then it was washed with deionized water to obtain AgNPs@Ta3N5 / Ti x Si y Photoelectrode.

[0051] The multilayer film structure of the Ta3N5-based photoelectrode includes a Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nanometal particles, the thickness of each layer is 2nm, 100nm, 50nm, 500nm and 25nm respectively.

[0052] Example 2

[0053] According to the general formula Ti x Si y, where x / y = 0.1 to prepare AgNPs@Ta3N5 / Ti x Si y .

[0054] The size is 10×20×1mm 3 A quartz glass substrate was used and cleaned sequentially with acetone, anhydrous ethanol, and deionized water. A 50 nm thick Ti layer was deposited on the quartz substrate by sputtering, followed by a 100 nm thick Pt layer. The sample was partially masked to expose an area of ​​10 × 10 mm. 2 Then, a Ti layer with a thickness of 2 nm, a SiO2 layer with a thickness of 20 nm, and a Ta2O5 layer with a thickness of 600 nm were deposited in sequence by sputtering. During the magnetron sputtering process, Ar gas was introduced into the chamber at a rate of 37 sccm, and the minimum vacuum degree was maintained at 5.0E. -6 Ta3N5 / Ti was obtained by thermal nitriding Ta2O5 / SiO2 / Ti / Pt / Ti thin films in a horizontal quartz tube furnace, heating from room temperature to 980℃ at a rate of 5℃ / min under ambient pressure, holding for 5 hours, and naturally cooling to room temperature. x Si y During this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the processing chamber.

[0055] Prepare a precursor solution containing 88mL of high-purity water, 1mL of 0.01M AgNO3, and 10mL of 0.01M sodium citrate. Stir at 1200r / min for 20 minutes, then slowly add 0.8mL of 0.01M NaBH4 and stir for 30 seconds. After stirring, the precursor solution was irradiated with 550nm monochromatic light in a 40℃ water bath for 14 hours to obtain a AgNPs solution with a concentration of 0.1mol / L. Add 1.2mL of the AgNPs solution to the exposed area of ​​the sample (10×10mm 2 ) and spread evenly; the sample was placed on a hot plate at 100 ° C for 50 minutes. Then it was washed with deionized water to obtain AgNPs@Ta3N5 / Ti x Si y Photoelectrode.

[0056] The multilayer film structure of the Ta3N5-based photoelectrode includes a Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nanometal particles, the thickness of each layer is 50nm, 100nm, 2nm, 600nm and 50nm respectively.

[0057] Example 3

[0058] According to the general formula Tix Si y , where x / y = 0.2 to prepare CuNPs@Ta3N5 / Ti x Si y .

[0059] The size is 10×20×1mm 3 A quartz glass substrate was used and cleaned sequentially with acetone, anhydrous ethanol, and deionized water. A 25 nm thick Ti layer was deposited on the quartz substrate by sputtering, followed by a 150 nm thick Pt layer. The sample was partially masked to expose an area of ​​10 × 10 mm. 2 Then, a Ti layer with a thickness of 10 nm, a SiO2 layer with a thickness of 50 nm, and a Ta2O5 layer with a thickness of 650 nm were deposited in sequence by sputtering. During the magnetron sputtering process, Ar gas was introduced into the chamber at a rate of 37 sccm, and the minimum vacuum degree was maintained at 5.0E. -6 Ta3N5 / Ti was obtained by thermal nitriding Ta2O5 / SiO2 / Ti / Pt / Ti thin films in a horizontal quartz tube furnace, heating from room temperature to 960℃ at a rate of 5℃ / min under ambient pressure, holding for 5 hours, and naturally cooling to room temperature. x Si y During this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the processing chamber.

[0060] Prepare a precursor solution containing 88mL of high-purity water, 1mL of 0.01M Cu(NO3)2 and 10mL of 0.01M sodium citrate, stir at 1200r / min for 20 minutes, then slowly add 0.8mL of 0.01M NaBH4 and stir for 30 seconds. After stirring, the precursor solution was irradiated with 550nm monochromatic light in a 40℃ water bath for 14 hours to obtain a CuNPs solution with a concentration of 0.1mol / L. Add 1.8mL of CuNPs solution to the exposed area of ​​the sample (10×10mm 2 ) and spread evenly; the sample was placed on a hot plate at 100 ° C for 40 minutes. Then it was washed with deionized water to obtain CuNPs@Ta3N5 / Ti x Si y Photoelectrode.

[0061] The multilayer film structure of the Ta3N5-based photoelectrode includes a Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nanometal particles, the thickness of each layer is 25nm, 150nm, 30nm, 650nm and 75nm respectively.

[0062] Example 4

[0063] According to the general formula Ti x Si y , where x / y = 5 to prepare CuNPs@Ta3N5 / Ti x Si y .

[0064] The size is 10×20×1mm 3 A quartz glass substrate was used and cleaned sequentially with acetone, anhydrous ethanol, and deionized water. A 50 nm thick Ti layer was deposited on the quartz substrate by sputtering, followed by a 200 nm thick Pt layer. The sample was partially masked to expose an area of ​​10 × 10 mm. 2 Then, a Ti layer with a thickness of 50nm, a SiO2 layer with a thickness of 10nm, and a Ta2O5 layer with a thickness of 700nm were deposited in sequence by sputtering. During the magnetron sputtering process, Ar gas was introduced into the chamber at a rate of 37sccm, and the minimum vacuum degree was maintained at 5.0E. -6 Ta3N5 / Ti was obtained by thermal nitriding Ta2O5 / SiO2 / Ti / Pt / Ti thin films in a horizontal quartz tube furnace, heating from room temperature to 940℃ at a rate of 5℃ / min under ambient pressure, holding for 5 hours, and naturally cooling to room temperature. x Si y During this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the processing chamber.

[0065] Prepare a precursor solution containing 88mL of high-purity water, 1mL of 0.01M Cu(NO3)2 and 10mL of 0.01M sodium citrate, stir at 1200r / min for 20 minutes, then slowly add 0.8mL of 0.01M NaBH4 and stir for 30 seconds. After stirring, the precursor solution was irradiated with 550nm monochromatic light in a 40℃ water bath for 14 hours to obtain a CuNPs solution with a concentration of 0.1mol / L. Add 2.4mL of CuNPs solution to the exposed area of ​​the sample (10×10mm 2 ) and spread evenly; the sample was placed on a hot plate at 100 ° C for 30 minutes. Then it was washed with deionized water to obtain CuNPs@Ta3N5 / Ti x Si y Photoelectrode.

[0066] The multilayer film structure of the Ta3N5-based photoelectrode includes a Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nanometal particles, the thickness of each layer is 50nm, 200nm, 50nm, 700nm and 100nm respectively.

[0067] Comparative Examples 1-7

[0068] Photoelectrode products were prepared according to the following documents.

[0069] Comparative Example 1: Y. Xiao, Z. Fan, M. Nakabayashi, Q. Li, L. Zhou, Q. Wang, C. Li, N. Shibata, K. Domen, Y. Li, Energy Environ. Sci. 2016, 9, 1327.

[0070] Comparative Example 2: X.Zhang, H.Guo, G.Dong, Y.Zhang, G.Lu, Y.Bi, Appl.Catal.B-Environ.2020,277,119217.

[0071] Comparative Example 3: C.Dong,X.Zhang,Y.Ding,Y.Zhang,Y.Bi,Appl.Catal.B-Environ.2023,338,123055.

[0072] Comparative Example 4: J.Fu, Z.Fan, M.Nakabayashi, H.Ju, N.Pastukhova, Y.Xiao, C.Feng, N.Shibata, K.Domen, Y.Li, Nat.Commun.2022,13,729.

[0073] Comparative Example 5: P.Wang, C.Ding, Y.Deng, H.Chi, H.Zheng, L.Liu, H.Li, Y.Wu, X.Liu, J.Shi, C.Li, ACS Catal.2023,13,2647.

[0074] Comparative Example 6: Y. Pihosh, V. Nandal, R. Shoji, R. Bekarevich, T. Higashi, V. Nicolosi, H. Matsuzaki, K. Seki, K. Domen, ACS Energy Lett. 2023, 8, 2106.

[0075] Comparative Example 7: Y.Pihosh, V.Nandal, T.Higashi, R.Shoji, R.Bekarevich, H.Nishiyama, T.Yamada, V.Nicolosi, T.Hisatomi, H.Matsuzaki, K.Seki, K.Domen, Adv.EnergyMater.2023,13,2301327.

[0076] Part III Test Results and Data Analysis

[0077] 1. Observation using electron microscope equipment

[0078] Figure 2 The MNPs@Ta3N5 / Ti prepared in Example 1 of the present invention x Si y The SEM images (longitudinal cross-section) of the product at different magnifications show that polycrystals and some small pores of several hundred nanometers in size can be seen inside the product. This is due to the fact that oxygen vacancies in the Ta2O5 precursor film are replaced by nitrogen vacancies during the nitridation process to form the characteristics of the Ta3N5 film. During the nitridation process, a dense conductive layer (Ti x Si y ), Ti x Si y Effectively bonds Ta3N5 to the Pt layer.

[0079] 2. Photocurrent density comparison test

[0080] A test system was built with reference to the aforementioned method of using the photoelectrode product, and the products of the embodiment and comparative examples were tested respectively. Figure 3 The photocurrent density of the present invention is compared with that of the existing product in the comparative example.

[0081] As can be seen from the figure, taking the test results of Example 1 of the present invention as an example, the photocurrent density can reach 12.73 mA cm -2 (marked by a five-pointed star in the figure); the photocurrent density in the references of Comparative Examples 1-7 is smaller than the photocurrent density of this work, 12.73 mA cm -2 (The block marks in the figure and the numbers next to the marks refer to the serial numbers of the comparative examples).

[0082] Therefore, the MNPs@Ta3N5 / Ti x Si y The material can achieve high photocurrent density and excellent performance, exceeding other existing photoelectrode products.

[0083] In summary, in the photoelectrode product of the present invention, Ti x Si yThe layer can effectively bond Ta3N5 to Pt noble metal, and further bond it to the quartz substrate based on the Ti metal layer, which can save the amount of noble metal and expand the scope of application. x Si y The layer can enhance the separation and migration of photoinduced EHPs by UV-visible light; on the other hand, Ti x Si y The Fermi levels of Ta3N5 and Ta3N5 are 4.55eV and 4.14eV respectively, and their energy levels are adapted to improve the transport of photogenerated carriers. x Si y Metals such as Ag and Cu are loaded on the film layer to achieve photothermal and photoelectric coupling.

[0084] Finally, it should be noted that the above examples are merely specific embodiments of the present invention. Clearly, the present invention is not limited to the above examples, and many variations are possible. The present invention may be summarized in other specific forms that do not violate the spirit and key features of the present invention. Therefore, no matter from which point of view, the above embodiments of the present invention can only be considered as illustrative of the present invention and not as limiting thereof. Any variations within the meaning and scope of the claims of the present invention should be considered as included within the scope of the claims.

Claims

1. A Ta3N5-based photoelectrode based on magnetron sputtering, characterized in that: The Ta3N5-based photoelectrode is based on quartz glass as a substrate, and has a multilayer film structure formed on the substrate based on magnetron sputtering and after thermal nitridation and coating treatment; the multilayer film structure includes, from bottom to top, a first Ti metal layer, a Pt conductive metal layer, a Ti x Si y layer, Ta3N5 layer and MNPs nano metal particles; the Ti x Si y The layer is a uniform material layer formed by the reaction of the second Ti metal layer and the SiO2 layer after thermal nitridation treatment, and the Ta3N5 layer is a uniform material layer formed by the reaction of the Ta2O5 layer and NH3 after combination and transformation; the MNPs metal particles contain Ag or Cu, M refers to Ag or Cu with photothermal properties; the Ti x Si y The x and y in the layer name are determined according to the thickness ratio x / y of the second Ti metal layer to the SiO2 layer, and the value range of x / y is 0.02~5.

2. The Ta3N5-based photoelectrode according to claim 1, characterized in that The thickness of the first Ti metal layer is in the range of 2 to 50 nm, the thickness of the Pt conductive metal layer is in the range of 100 to 200 nm, and the thickness of the Ti x Si y The thickness of the Ta3N5 layer ranges from 2 to 50 nm, the thickness of the Ta3N5 layer ranges from 500 to 700 nm; the thickness of the MNPs nanometal particles is 25 to 100 nm.

3. The method for preparing a Ta3N5-based photoelectrode based on magnetron sputtering according to claim 1, characterized in that: The following steps are involved: (1) Use a quartz glass plate of appropriate size as the substrate and clean it with acetone, anhydrous ethanol and deionized water in sequence; (2) First, a first Ti metal layer and a Pt conductive metal layer are deposited on the substrate in sequence using a magnetron sputtering process; according to the design of the photoelectrode, the area reserved for conduction is partially masked, and then a second Ti metal layer, a SiO2 layer, and a Ta2O5 layer are deposited in sequence using a magnetron sputtering process; (3) The sample that has completed the multilayer deposition process is moved into a horizontal quartz tube furnace for thermal nitriding treatment. During this process, the second Ti metal layer and the SiO2 layer react and combine to form a uniform Ti x Si y layer, the Ta2O5 layer combines with NH3 to transform into a uniform Ta3N5 layer; (4) A metal nanoparticle (MNPs) precursor solution was prepared by the reduction method, and it was dropped onto the Ta3N5 layer on the sample surface and spread evenly; after drying, it was washed with deionized water to obtain a Ta3N5-based photoelectrode, which was recorded as MNPs@Ta3N5 / Ti x Si y Photoanode.

4. The method according to claim 3, characterized in that During the magnetron sputtering process in step (2), the deposition thickness of each layer on the sample is: the first Ti metal layer is 2 to 50 nm, the Pt metal conductive layer is 100 to 200 nm; the second Ti metal layer is 2 to 50 nm, the SiO2 layer is 10 to 100 nm, and the Ta2O5 layer is 500 to 700 nm.

5. The method according to claim 3, characterized in that During the magnetron sputtering process in step (2), Ar gas was introduced into the magnetron sputtering chamber at a rate of 37 sccm, and the minimum vacuum was maintained at 6.7×10 -7 MPa.

6. The method according to claim 3, characterized in that During the thermal nitridation treatment in step (3), the sample is heated from room temperature to 940-1000°C at a rate of 5°C / min under normal pressure, kept at this temperature for 5 hours, and then naturally cooled to room temperature; during this process, flowing ammonia gas is introduced to maintain an ammonia atmosphere in the treatment chamber.

7. The method according to claim 3, characterized in that The concentration of the MNPs precursor solution in step (4) is 0.1 mol / L, and the amount of addition is 0.6-2.4 mL / cm 2 .

8. The method according to claim 3, characterized in that The drying treatment in step (4) refers to placing the sample on a heating plate at 100°C for drying for 30 to 60 minutes.

9. The method according to claim 3, characterized in that The coating thickness of the MNPs precursor solution is controlled so that the thickness of the MNPs nanometal particles on the surface of the Ta3N5-based photoelectrode after drying is 25~100 nm.

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