Electrocatalytic material of multi-metallic titanium oxide supported on titanium-based carrier and preparation method and application thereof

Abstract

This invention discloses an electrocatalytic material of multi-metal titanium oxide supported on a titanium-based support, its preparation method, and its applications. The method involves pretreating the titanium-based support with borohydride to construct a rough activation layer on its surface. A precursor solution containing one or more metal ions is then loaded onto the titanium-based surface. After drying, the solution is calcined at a specific temperature to form a multi-metal titanium oxide catalytic layer in situ on the titanium-based support. The process of this invention is simple, the conditions are mild, and the types and composition of metals can be flexibly controlled. The integrated titanium-based multi-metal titanium oxide electrode prepared by this method exhibits both high activity and high stability, and is expected to reduce the cost of hydrogen production through water electrolysis, and is suitable for industrial applications of hydrogen production through water electrolysis.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical catalysis technology, specifically relating to an electrocatalytic material with multi-metal titanium oxides supported on a titanium-based support, its preparation method, and its application. Background Technology

[0002] Against the backdrop of escalating energy shortages and environmental pressures, electrochemical energy conversion and utilization technologies (such as water electrolysis for hydrogen / oxygen production, fuel cells, CO2 electroreduction, and organic electrooxidation / reduction) have attracted widespread attention. These systems generally involve various electrocatalytic reactions at the anode and / or cathode, including the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and various small-molecule redox reactions. These reactions often exhibit slow kinetics, requiring efficient and stable electrocatalytic materials for acceleration. In practical applications, the electrolyte environment can be acidic, alkaline, or neutral, placing more stringent and diverse demands on the activity, stability, and conductivity of the catalyst under different operating conditions. On the one hand, the catalyst needs to maintain low overpotentials and good reaction kinetics over a wide pH range to adapt to different types of electrolyzers and electrochemical devices; on the other hand, the electrode must also possess excellent mechanical stability, corrosion resistance, and long-term operational durability under high current densities. Traditional electrode structures often employ a method of mixing powdered catalyst with binder and then coating it onto the surface of the current collector. This structure suffers from problems such as high interfacial contact resistance, easy detachment of the catalyst layer, and limited mass transfer, making it difficult to meet the requirements of high power density and long-life operation.

[0003] Existing integrated electrode fabrication methods still have the following shortcomings: First, the fabrication process involves many steps and relatively complex conditions, making it difficult to achieve simple and scalable fabrication on porous titanium felt and other supports. Second, the types and ratios of metals in existing systems are limited, which is not conducive to constructing multi-metal or even high-entropy oxide systems in a larger compositional space, thereby systematically controlling the electronic and defect structures of the catalytic interface. Third, some methods do not sufficiently activate the titanium-based surface, making it difficult to simultaneously obtain a rough, multi-defect interface, good wettability, and strong metal-support bonding, resulting in the need to improve the long-term stability of the electrode under various electrolytes and electrocatalytic reaction conditions. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention aims to provide an electrocatalytic material of multi-metal titanium oxide supported on a titanium-based support, its preparation method, and its application, which enables the in-situ construction of multi-metal titanium oxide (MTiO) with tunable composition on a titanium-based support. xThe electrode is formed by combining a catalytic layer of high-entropy titanium oxide with a high-entropy titanium oxide layer. It is suitable for various electrolyte systems, including acidic, alkaline and neutral electrolytes, as well as various electrocatalytic reactions. Thus, while taking into account both high activity and high stability, it provides a versatile catalytic material preparation scheme for different electrochemical energy conversion and utilization devices.

[0005] To achieve the above objectives, the present invention employs the following technical solution: This invention discloses a method for preparing an electrocatalytic material with multi-metal titanium oxides supported on a titanium-based support, comprising the following steps: 1) The titanium-based support is pretreated in a system containing a borohydride reducing agent to obtain a surface-activated and porous titanium-based support; 2) Load the metal precursor onto the surface of the titanium-based support after step 1) to obtain a titanium-based precursor electrode loaded with the metal precursor; 3) The titanium-based precursor electrode loaded with the metal precursor is dried and then annealed to convert the metal precursor into a multi-metal titanium oxide catalytic layer in situ on the titanium substrate surface, thus obtaining the electrocatalytic material MTiO loaded with multi-metal titanium oxide on a titanium-based support. x @TM, where M represents a metallic element, and 1≤x≤4.

[0006] Preferably, the titanium-based carrier is at least one of titanium felt, titanium mesh, titanium foil, titanium foam, or other porous titanium and titanium alloy materials; the borohydride reducing agent is preferably NaBH4, and may also be KBH4, LiBH4, or mixtures thereof; the pretreatment conditions include: reducing agent dosage, treatment temperature, treatment time, etc., and by adjusting the above conditions, an activated interface layer with a rough porous structure, defect sites, and good wettability is formed on the titanium-based surface.

[0007] As a more preferred embodiment, in step 1), the pretreatment method is as follows: the titanium felt treated with oxalic acid is spread flat on top of the NaBH4 powder in the crucible, and then covered with another layer of NaBH4 powder, so that the titanium felt is between the upper and lower layers of NaBH4. The mixture is heated to 200-500 ℃ in air or an inert atmosphere and kept at that temperature for 1-6 h, and then cooled to obtain the titanium felt carrier pretreated with NaBH4.

[0008] Preferably, the metal precursor solution is loaded onto the surface of a pretreated titanium-based support by dropping, impregnation, spraying, or other wet chemical methods to obtain a titanium-based precursor electrode loaded with the metal precursor; wherein, the metal M is selected from one or more metals such as Ru, Ir, V, Fe, Co, Ni, Mn, Cu, Mo, Cr, Pr, Rh, Sn, W, Os, Pt, Pd, Pb, Re, Te, Zn, Hg, Ge, Nb, and Ta; the metal salt is a soluble precursor such as chloride, nitrate, sulfate, acetate, or organometallic salt; the solvent can be water, ethylene glycol, alcohol, or a water / alcohol mixture.

[0009] As a more preferred option, when there are one or two metal elements, a binary or multi-element MTiO is formed. x Solid solution; when there are three or more metal elements, a high-entropy multimetallic titanium oxide catalytic layer is formed.

[0010] As a more preferred embodiment, in step 2), the multi-metal precursor solution used for dropwise addition or impregnation is obtained by dissolving 1 mg of multi-metal salt (based on the total mass of metal) in a mixed solvent of 40 µL of water and 40-240 µL of ethylene glycol, wherein the volume ratio of water to alcohol solvent is 1:(1-6).

[0011] Preferably, in step 3), the drying conditions are: drying at 50-200 ℃ in a forced-air drying oven for 1-5 h.

[0012] Preferably, in step 4), the dried precursor electrode is calcined in air at 400-700 °C for 1-6 h, with a heating rate of 1-20 °C / min. -1 This allows the multi-metal precursor to be fully converted into a multi-metal titanium oxide or high-entropy titanium oxide catalyst layer.

[0013] Preferably, during annealing, the dried precursor electrode is placed in a heat treatment apparatus and calcined in an oxygen-containing atmosphere or an inert / oxygen-containing mixed atmosphere, so that the multi-metal precursor reacts with the surface of the titanium-based support to form a multi-metal titanium oxide solid solution or a high-entropy titanium oxide catalytic layer in situ on the surface of the titanium-based support, thereby obtaining an integrated multi-metal titanium oxide electrocatalytic electrode.

[0014] Accordingly, the present invention also provides an integrated multi-metal titanium oxide electrocatalytic electrode on a titanium-based support prepared by the above-described method. The electrode comprises a titanium-based support and a multi-metal titanium oxide catalytic layer grown in situ on its surface, wherein the catalytic layer comprises binary or multi-component MTiO. x Solid solution and / or high-entropy multimetallic titanium oxide structure.

[0015] Furthermore, the present invention also discloses the application of the above-mentioned integrated multi-metal titanium oxide electrocatalytic electrode in electrochemical reactions, including but not limited to: serving as hydrogen evolution reaction (HER) and / or oxygen evolution reaction (OER) electrodes in acidic, alkaline or neutral electrolytes for water splitting reactions; serving as ORR / OER electrodes in fuel cells or metal-air batteries; and serving as anodes and / or cathodes in other electrocatalytic reactions such as CO2 electroreduction and oxidation / reduction of small organic molecules.

[0016] Preferred, RuTiO x @TM is composed of uniformly distributed and densely packed nanorods.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses a method for preparing electrocatalytic materials with multi-metal titanium oxides loaded on a titanium-based support. The method involves pretreating the titanium-based support with a borohydride, followed by multi-metal precursor solution loading and thermal conversion (drying and annealing). This preparation process uses simple equipment and mild conditions, eliminating the need for complex vacuum systems or multi-step sol-gel / vapor deposition processes required by existing technologies. It is suitable for large-area continuous processing on porous titanium-based supports such as titanium felt. On one hand, NaBH4 pretreatment introduces a rough porous structure and defect sites on the titanium-based surface, which facilitates uniform wetting and firm anchoring of the multi-metal precursor. This significantly reduces the interfacial contact resistance between the active layer and the current collector in traditional powder electrodes, minimizing the risk of catalyst layer peeling under high current density and long-term operation conditions, and improving the mechanical stability and structural durability of the electrode. On the other hand, the same process platform is compatible with various metal types and ratios, enabling the preparation of both binary and multi-component MTiO. x Solid solutions can also be used to construct high-entropy multimetallic titanium oxide catalytic layers, exhibiting good versatility and scalability.

[0018] Furthermore, the metal elements in the metal precursor used in this invention are flexibly adjustable, enabling the construction of high-entropy multi-metal systems. This invention employs a solution-supported multi-metal precursor method, allowing for flexible design of the catalytic layer composition within a wide compositional space by changing the types and molar ratios of metal salts. This enables the preparation of RuTiO₂. x IrTiO x VTiO x RuIrTiO x Binary or multi-component MTiO x Solid solutions can also be constructed using RuIrVMnCrTiO x High-entropy titanium oxide systems containing multiple transition metals. The synergistic effect of multiple metals and the high-entropy effect are beneficial for controlling the electronic structure, defect concentration, and diversity of active sites, providing a wealth of design freedom for optimizing the interface structure for different electrocatalytic reactions.

[0019] Furthermore, this invention achieves both low precious metal usage and excellent overall performance by doping / co-doping precious metals (such as Ru, Ir, Pt, etc.) with non-precious metals (such as V, Fe, Co, Ni, Mn, Cr, etc.) into the titanium oxide framework. This significantly improves the utilization efficiency of precious metals, maintaining or enhancing catalytic performance while reducing the overall amount of precious metals used. The synergistic effect of multiple metals and the introduction of defects such as oxygen vacancies are beneficial for optimizing the adsorption-desorption behavior of intermediates, lowering the reaction energy barrier, and inhibiting excessive oxidation and dissolution of precious metals, thus achieving both high activity and high stability.

[0020] The integrated multi-metal titanium oxide electrocatalytic electrode on a titanium-based support prepared by the method of this invention is suitable for various electrolytes and electrocatalytic reactions. Benefiting from the corrosion resistance of the titanium-based support and the structural stability of the multi-metal titanium oxide catalyst layer, the electrode can operate in various electrolytes, including acidic, alkaline, and neutral electrolytes, and is suitable for water splitting (HER / OER), ORR, and various small molecule oxidation / reduction reactions. By selecting different metal combinations and ratios, the catalytic activity and selectivity can be controlled for specific reactions, achieving a single preparation method applicable to multiple electrocatalytic applications. The electrocatalyst performance of this invention is based on RuTiO2. x As a representative example, it demonstrates that it can simultaneously serve as a cathode for hydrogen production and an anode for oxygen production in water electrolysis, achieving a yield of 10 mA cm⁻¹ in an acidic electrolyte of 0.5 M H₂SO₄. -2 The overpotential of the OER is 248 mV, and the overpotential of the HER is 46 mV. It can operate stably in alkaline, neutral, and seawater electrolytes. In a three-electrode system at 10 mA cm⁻¹... -2 It can work stably for 400 hours. Attached Figure Description

[0021] Figure 1 RuTiO2 prepared in Example 1 x @TM's XRD pattern; Figure 2 RuTiO2 prepared in Example 1 x @TM's SEM image; Figure 3 RuTiO2 prepared in Example 1 x XAS spectrum of @TM; Figure 4 RuTiO2 prepared in Example 1 x Performance graphs of @TM in water oxidation / reduction in 0.5 M H2SO4; where a) is the LSV graph of OER; b) is the LSV graph of HER; Figure 5 RuTiO2 prepared in Example 1 xStability diagram of @TM in water oxidation / reduction in 0.5 M H2SO4. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] The present invention will now be described in further detail with reference to the accompanying drawings: All raw materials involved in this application are commercially available.

[0025] This invention provides a method for preparing an integrated multi-metal titanium oxide electrocatalytic material on a titanium-based support, comprising the following steps: 1) The titanium-based support is pretreated in a borohydride-containing system to obtain a surface-activated titanium-based support; 2) A precursor solution containing one or more metal ions is loaded onto the surface of a pretreated titanium-based support by means of drop addition, impregnation or spraying to obtain a titanium-based precursor electrode loaded with metal precursor; 3) The titanium-based precursor electrode is dried and then heat-treated in an oxygen-containing atmosphere or air to convert the metal precursor into a multi-metal titanium oxide catalytic layer in situ on the titanium-based surface, thus obtaining an integrated electrocatalytic electrode MTiO. x @TM, where 1≤x≤4.

[0026] In this invention, the titanium-based support can be porous titanium materials such as titanium felt, titanium mesh, titanium foil, and titanium foam; the borohydride reducing agent is preferably NaBH4, but can also be other borohydrides that can produce similar effects; the metal M can be selected from one or more of the following metals: Ru, Ir, V, Fe, Co, Ni, Mn, Cu, Mo, Cr, Pr, Rh, Sn, W, Os, Pt, Pd, Pb, Re, Te, Zn, Hg, Ge, Nb, and Ta; and the resulting catalyst layer can be either binary or multi-component MTiO. x Solid solutions can also be high-entropy multimetallic titanium oxides containing multiple metals.

[0027] Note that if Ru has the standard coordination number, it is generally denoted as MTiO2. However, the introduction of transition metal ions as doping leads to the formation of oxygen vacancies in the crystal lattice, which is no longer the standard coordination number. Therefore, it is generally denoted as MTiO2. x .

[0028] Specifically, the method of the present invention includes the following steps: 1) Take a 1 cm × 1.5 cm titanium felt and treat it in a 10 wt% oxalic acid solution at 75 ℃ for 1 h. Clean it ultrasonically with deionized water and ethanol for 10 min each, then dry it for later use. Weigh an appropriate amount of NaBH4 powder and place it at the bottom of a porcelain crucible. Spread the titanium felt evenly on the NaBH4 powder, then cover it with another layer of NaBH4 powder, ensuring the titanium felt is positioned between the two layers of NaBH4. Place the crucible in a muffle furnace and heat it at 5 ℃·min in an air atmosphere. -1 The temperature was raised to 350 °C, held for 3 h, and then naturally cooled to room temperature to obtain a titanium felt carrier pretreated with NaBH4.

[0029] 2) Weigh 1 mg of RuCl3·3H2O and dissolve it in a mixed solvent consisting of 40 μL of deionized water and 160 μL of ethylene glycol, forming a homogeneous solution under magnetic stirring. Add the above 150 μL Ru precursor solution dropwise evenly to a titanium felt pretreated with NaBH4, ensuring the solution fully wets the titanium felt. Allow it to stand for a period of time to ensure sufficient adsorption of the Ru precursor, thus obtaining the Ru precursor electrode.

[0030] 3) The above precursor electrode was placed in a drying oven and dried at 70 °C for 3 h to obtain a dried precursor electrode. It was then placed in a muffle furnace and dried at 5 °C / min in an air atmosphere. - ¹ The temperature was raised to 500 °C, held for 3 h, and then allowed to cool naturally to room temperature to obtain RuTiO₂. x @TM Integrated Electrode.

[0031] The present invention will be further described below with reference to the embodiments.

[0032] Example 1 1) A 1 cm × 1.5 cm titanium felt was treated in a 10 wt% oxalic acid solution at 75 ℃ for 1 h, then ultrasonically cleaned with deionized water and ethanol for 10 min each, and dried for later use. An appropriate amount of NaBH4 powder was placed at the bottom of a porcelain crucible. The dried titanium felt was then spread evenly on top of the NaBH4 powder, and then covered with another layer of NaBH4 powder, ensuring the titanium felt was positioned between the two layers of NaBH4. The crucible was placed in a muffle furnace and heated at 5 ℃·min in air. -1 The temperature was raised to 350 ℃ and held for 3 h. After cooling naturally to room temperature, the titanium felt carrier pretreated with NaBH4 was removed.

[0033] 2) Weigh 1 mg of RuCl3·3H2O and dissolve it in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol to form a homogeneous precursor solution under magnetic stirring. Add the Ru precursor solution evenly dropwise onto the pretreated titanium felt to fully impregnate the titanium fibers and pores. Allow it to stand for a certain period to ensure sufficient adsorption of the Ru precursor, thus obtaining a Ru precursor / titanium felt precursor electrode.

[0034] 3) Place the precursor electrode in a drying oven and dry it at 70 °C for 3 h to obtain a dried precursor electrode. Then, heat it in a muffle furnace at 5 °C / min. -1 Heating to 500 °C and holding in air for 3 hours, followed by natural cooling, yields RuTiO₂. x @TM integrated electrode.

[0035] Figure 1 RuTiO2 prepared in Example 1 x As shown in Figure 1, the XRD pattern of the @TM catalyst shows that the main diffraction peaks of the sample correspond to the characteristic peaks of TiO2 and RuO2, indicating that a crystallized oxide layer was formed in situ on the surface of the titanium felt. Figure 2 RuTiO2 prepared in Example 1 x Scanning electron microscope image of the @TM catalyst, illustrating RuTiO x @TM is composed of uniformly distributed nanorods. Figure 3 RuTiO2 prepared in Example 1 x The XAS spectrum of @TM, comparing and illustrating the Ru in the catalyst. 4+ The increased content leads to a rise in oxygen vacancy content, thereby enhancing catalytic activity and conductivity.

[0036] The RuTiO prepared in Example 1 x The @TM catalyst was drop-coated onto glassy carbon as the working electrode, a mercurous sulfate electrode was used as the reference electrode, and a carbon rod was used as the counter electrode. Electrochemical performance was tested using an electrochemical workstation in 0.5 M H₂SO₄ solution. The linear sweep spectroscopy curve of the oxygen production reaction is shown below. Figure 4 As shown. RuTiO2 prepared in Example 1 x @TM reaches 10 mA cm -2 The oxygen production overpotential at current density is 248 mV, reaching 10 mA cm⁻¹. -2 The hydrogen production overpotential at the current density is 46 mV. RuTiO x The oxygen production stability test results of the @TM catalyst are as follows: Figure 5 As shown, it can achieve 10 mA cm -2 The RuTiO2O3 operated stably for 400 hours at a current density of 0.5 M H2SO4 without significant performance degradation, indicating that its performance is stable. x The @TM catalytic electrode exhibits good catalytic stability.

[0037] Example 2 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0038] By replacing RuCl3·3H2O in Example 1 with an equimolar amount of IrCl3·3H2O, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, IrTiO2 can be obtained. x @TM integrated electrode.

[0039] Example 3 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0040] By replacing RuCl3·3H2O in Example 1 with an equimolar amount of VCl3, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, VTiO2 can be obtained. x @TM integrated electrode.

[0041] Example 4 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0042] By replacing RuCl3·3H2O in Example 1 with an equimolar amount of MnCl2·4H2O, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, MnTiO2 can be obtained. x @TM integrated electrode.

[0043] Example 5 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0044] By replacing RuCl3·3H2O with an equimolar amount of CrCl3·6H2O in Example 1, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, CrTiO2 can be obtained. x @TM integrated electrode.

[0045] Example 6 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0046] By replacing RuCl3·3H2O in Example 1 with an equimolar amount of FeCl3·6H2O, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, FeTiO2 can be obtained. x @TM integrated electrode.

[0047] Example 7 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0048] By replacing RuCl3·3H2O in Example 1 with an equimolar amount of Ni(NO3)2·6H2O, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, NiTiO2 can be obtained. x @TM integrated electrode.

[0049] Example 8 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0050] By replacing RuCl3·3H2O with an equimolar amount of CoCO3 in Example 1, while keeping the NaBH4 pretreatment conditions, precursor solution ratio, and drying and calcination conditions unchanged, CoTiO2 can be obtained. x @TM integrated electrode.

[0051] Example 9 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0052] Weigh out RuCl3·3H2O, IrCl3·3H2O, VCl3, Fe(NO3)3·9H2O, and Co(NO3)2·6H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrVFeCoTiO x @TM integrated electrode.

[0053] Example 10 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0054] Weigh out RuCl3·3H2O, IrCl3·3H2O, VCl3, MnCl2·4H2O, and CoCl2·6H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol, and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrVMnCoTiO2. x @TM integrated electrode.

[0055] Example 11 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0056] Weigh out RuCl3·3H2O, IrCl3·3H2O, CrCl3·6H2O, MnCl2·4H2O, and NiCl2·6H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrCrMnNiTiO2. x @TM integrated electrode.

[0057] Example 12 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0058] Weigh out RuCl3·3H2O, IrCl3·3H2O, CrCl3·6H2O, Mn(NO3)2·4H2O, and NiCl2·6H2O, mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg, and dissolve them in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol. Stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrCrMnNiTiO2. x @TM integrated electrode.

[0059] Example 13 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0060] Weigh out RuCl3·3H2O, IrCl3·3H2O, VCl3, Cr(NO3)3·9H2O, and MnCl2·4H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrCrMnVTiO2. x @TM integrated electrode.

[0061] Example 14 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0062] Weigh out RuCl3·3H2O, IrCl3·3H2O, CrCl3·6H2O, MnCl2·4H2O, NiCO3, and HAuCl4·3H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrCrMnNiAuTiO x @TM integrated electrode.

[0063] Example 15 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0064] Weigh out RuCl3·3H2O, IrCl3·3H2O, PrCl3·6H2O, RhCl3·3H2O, NiCO3, and CrCl3·6H2O and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuIrPrRhNiCrTiO. x @TM integrated electrode.

[0065] Example 16 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0066] Weigh out RuCl3·3H2O, SnCl2·2H2O, WCl6, OsCl3, H2PtCl6·6H2O, and PdCO3 in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol, and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuSnWOsPtPdTiO2. x @TM integrated electrode.

[0067] Example 17 This embodiment only changes the type of metal precursor; the remaining steps are the same as in Embodiment 1.

[0068] Weigh out RuCl3·3H2O, PbCl2, ReCl5, Zn(NO3)2·6H2O, HgCl2, NbCl5, and TaCl5 and mix them in a molar ratio of 1:1:1:1:1 to make a total metal mass of 1 mg. Dissolve the mixture in a mixed solution of 40 μL deionized water and 160 μL ethylene glycol and stir to form a homogeneous high-entropy multi-metal precursor solution. Add this solution uniformly dropwise onto a pretreated titanium felt to obtain RuPbReZnHgNbTaTiO x @TM integrated electrode.

[0069] Example 18 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0070] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 40 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0071] Example 19 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0072] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 80 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0073] Example 20 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0074] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 120 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0075] Example 21 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0076] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 180 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0077] Example 22 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0078] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 200 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0079] Example 23 Except for the ethylene glycol content, the other steps are the same as in Example 1.

[0080] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 240 μL ethylene glycol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0081] Example 24 Except for the different types of alcohols, the other steps are the same as in Example 1.

[0082] 1 mg of RuCl3·3H2O was weighed and dissolved in a mixed solution of 40 μL deionized water and 160 μL ethanol, and stirred to form a homogeneous Ru metal precursor solution. This solution was then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0083] Example 25 Except for the different types of alcohols, the other steps are the same as in Example 1.

[0084] Weigh 1 mg of RuCl3·3H2O and dissolve it in a mixed solution of 40 μL deionized water and 160 μL isopropanol, stirring to form a homogeneous Ru metal precursor solution. This solution is then uniformly added dropwise onto a pretreated titanium felt to obtain RuTiO2. x @TM integrated electrode.

[0085] Example 26 Except for the calcination temperature, the other steps are the same as in Example 1.

[0086] The dried electrode was calcined at 400 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0087] Example 27 Except for the calcination temperature, the other steps are the same as in Example 1.

[0088] The dried electrode was calcined at 450 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0089] Example 28 Except for the calcination temperature, the other steps are the same as in Example 1.

[0090] The dried electrode was calcined at 600 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0091] Example 29 Except for the heating rate, the other steps are the same as in Example 1.

[0092] The dried electrode was calcined at 500 °C for 3 h at a heating rate of 3 °C / min to obtain RuTiO. x @TM.

[0093] Example 30 Except for the heating rate, the other steps are the same as in Example 1.

[0094] The dried electrode was calcined at 500 °C for 3 h at a heating rate of 8 °C / min to obtain RuTiO. x @TM.

[0095] Example 31 Except for the drying temperature, the other steps are the same as in Example 1.

[0096] The titanium felt loaded with the precursor solution was dried at 50 °C for 3 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO.x @TM.

[0097] Example 32 Except for the drying temperature, the other steps are the same as in Example 1.

[0098] The titanium felt loaded with the precursor solution was dried at 80 °C for 3 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0099] Example 33 Except for the drying temperature, the other steps are the same as in Example 1.

[0100] The titanium felt loaded with the precursor solution was dried at 1200 °C for 3 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0101] Example 34 Except for the drying time, the other steps are the same as in Example 1.

[0102] The titanium felt loaded with the precursor solution was dried at 70 °C for 1 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0103] Example 35 Except for the drying time, the other steps are the same as in Example 1.

[0104] The titanium felt loaded with the precursor solution was dried at 70 °C for 5 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0105] Example 36 Except for the drying time, the other steps are the same as in Example 1.

[0106] The titanium felt loaded with the precursor solution was dried at 70 °C for 8 h, and the dried electrode was calcined at 500 °C for 3 h at a heating rate of 5 °C / min to obtain RuTiO. x @TM.

[0107] Example 37 Except for the borohydride treatment temperature, the other steps are the same as in Example 1.

[0108] The titanium felt was treated with oxalic acid, dried, and then placed between NaBH4 powders. It was calcined at 200 °C for 3 h, followed by repeated washing with deionized water / ethanol. The subsequent preparation and loading of the single-metal solution were the same as in Example 1, yielding RuTiO₂. x @TM.

[0109] Example 38 Except for the borohydride treatment temperature, the other steps are the same as in Example 1.

[0110] The titanium felt was treated with oxalic acid, dried, and then placed between NaBH4 powders. It was calcined at 400 °C for 3 h, followed by repeated washing with deionized water / ethanol. The subsequent preparation and loading of the single-metal solution were the same as in Example 1, yielding RuTiO₂. x @TM.

[0111] Example 39 Except for the borohydride treatment temperature, the other steps are the same as in Example 13.

[0112] The titanium felt was treated with oxalic acid, dried, and then placed between NaBH4 powders. It was calcined at 600 °C for 3 h, followed by repeated washing with deionized water / ethanol. The subsequent preparation and loading of the multi-metal solution were the same as in Example 13, yielding RuIrCrMnVTiO. x @TM integrated electrode.

[0113] Example 40 Except for the types of borohydrides, the remaining steps are the same as in Example 1.

[0114] The titanium felt was treated with oxalic acid, dried, and then placed between KBH4 powders. It was calcined at 350 °C for 3 h, followed by repeated washing with deionized water / ethanol. The subsequent preparation and loading of the multi-metal solution were the same as in Example 1, yielding RuTiO₂. x @TM integrated electrode.

[0115] Example 41 Except for the types of borohydrides, the remaining steps are the same as in Example 1.

[0116] The titanium felt was treated with oxalic acid, dried, and then placed between LiBH4 powders. It was calcined at 350 °C for 3 h, followed by repeated washing with deionized water / ethanol. The subsequent preparation and loading of the multi-metal solution were the same as in Example 1, yielding RuTiO₂. x @TM integrated electrode.

[0117] This invention provides a titanium-based solid solution (MTiO). xThe preparation method of @TM (electrocatalyst) exhibits extremely high process versatility and potential for large-scale production. Based on the electrode samples prepared according to the above embodiments, this application conducted relevant OER and HER tests. The compatibility of this preparation system with multiple metal elements and stable experimental repeatability fully demonstrate its feasibility as a general strategy for large-scale industrial preparation. This "one method, multiple functions" characteristic greatly reduces the development threshold and production cost of high-performance electrocatalyst materials, providing crucial material support for achieving large-scale green hydrogen energy production. The results are shown in Tables 1-7 below.

[0118] Table 1

[0119] As shown in Table 1, this method is not limited to a specific single metal. Through simple process adjustments, a series of transition metal solid solution catalyst layers, including Ru, Ir, V, Mn, Cr, Fe, Ni, and Co, can be constructed in situ on a titanium substrate. In terms of actual performance, Example 1 (RuTiO₂) demonstrates this capability. x Materials represented by @TM exhibited excellent electrocatalytic activity. This result strongly proves that while simplifying the preparation process and eliminating the need for additional binders, this process did not sacrifice the electrochemical activity of the materials. On the contrary, it enhanced the exposure and stability of active sites through the structure-activity advantages of in-situ growth.

[0120] Table 2

[0121] The preparation method described in this invention exhibits unique advantages in constructing high-entropy / multi-component metal oxides. Experimental data (Examples 9-17) shown in Table 2 demonstrate that this process can overcome the limitations of traditional methods on the number of components, achieving in-situ synergistic loading of five or more metal elements on a titanium substrate. With increasing component complexity, the catalytic activity is further enhanced through the synergistic effect between multiple metals. This not only proves that this method is a universal platform for preparing high-performance, multi-component electrocatalysts, but also lays the theoretical and experimental foundation for their industrial application in complex electrochemical environments.

[0122] Table 3

[0123] Referring to Table 3, gradient experiments on ethylene glycol content in the range of 40-240 μL revealed that the material activity exhibited a significant "volcano-like" pattern with the amount added, reaching the optimal performance balance point at 160 μL (OER of 248 mV and HER of 46 mV). This strongly demonstrates the key regulatory role of ethylene glycol in the quality of the catalyst layer and the existence of the optimal ratio.

[0124] Table 4

[0125] Referring to Table 4, a comparison of the amount of ethylene glycol used and its use with similar alcohol solvents (ethanol, isopropanol) demonstrates that ethylene glycol can, through its unique regulatory effect, enable RuTiO2 to... x The @TM system achieved optimal electrocatalytic activity (OER: 248 mV, HER: 46 mV), providing solid data support for the process parameter range protected by this invention.

[0126] Table 5

[0127] Referring to Table 5, the calcination temperature maintained good catalytic activity within the range of 400℃-600℃, with the best performance observed at 500℃ (Example 1). Fluctuations in the heating rate within the range of 3℃ / min-8℃ / min had minimal impact on performance, with 5℃ / min being the optimal parameter balancing efficiency and activity.

[0128] Table 6

[0129] As shown in Table 6, drying temperature and time have a significant impact on material activity. Experiments revealed that drying at 70°C for 3 hours (Example 1) is the optimal process combination; excessively high drying temperature (e.g., 120°C) or excessively long / short drying time both lead to varying degrees of increase in OER and HER overpotentials, indicating that an appropriate solvent evaporation rate is crucial for forming the ideal precursor morphology.

[0130] Table 7

[0131] Referring to Table 7, the experimental results show that the reduction modification process described in this invention exhibits significant temperature sensitivity and chemical specificity. Treatment with NaBH4 at 350°C for 3 hours results in unexpected activity gains in the catalyst; deviations from this optimal temperature range or changes in the type of reducing agent (such as KBH4 or LiBH4) lead to a significant decline in catalytic performance. This establishes the uniqueness and superiority of using NaBH4 at 350°C as the core modification parameter in this process.

[0132] In summary, the integrated multi-metal titanium oxide electrocatalytic material on a titanium-based support and its preparation method provided by this invention have advantages such as simple process, adjustable composition, strong interface, and wide applicability, showing good application prospects in various electrochemical energy conversion and utilization devices. Specifically, the method of this invention involves pretreating the titanium-based support with NaBH4 to construct a rough activation layer on its surface, then drop-coating a precursor solution containing one or more metal ions onto the titanium-based surface. After drying, it is calcined at a certain temperature to form a multi-metal titanium oxide catalytic layer in situ on the titanium-based support. The process is simple, the conditions are mild, and the types and composition of metals can be flexibly controlled. This invention further utilizes RuTiO2. x As a representative example, it demonstrates that it can simultaneously serve as a cathode for hydrogen production and an anode for oxygen production in water electrolysis, achieving a yield of 10 mA cm⁻¹ in an acidic electrolyte of 0.5 M H₂SO₄. -2 The overpotential of the OER is 248 mV, and the overpotential of the HER is 46 mV. It can operate stably in alkaline, neutral, and seawater electrolytes. In a three-electrode system at 10 mA cm⁻¹... -2 This integrated titanium-based multimetal titanium oxide electrode, capable of stable operation for 400 hours, combines high activity and high stability, and is expected to reduce the cost of hydrogen production through water electrolysis, and is suitable for industrial water electrolysis hydrogen production applications.

[0133] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing an electrocatalytic material of multi-metal titanium oxide supported on a titanium-based support, characterized in that, Includes the following steps: 1) The titanium-based support is pretreated in a borohydride-containing system to obtain a surface-activated and porous titanium-based support; 2) Load the metal precursor onto the surface of the titanium-based support after step 1) to obtain a titanium-based precursor electrode loaded with the metal precursor; 3) The titanium-based precursor electrode loaded with the metal precursor is dried and then annealed to convert the metal precursor into a multi-metal titanium oxide catalytic layer in situ on the titanium substrate surface, thus obtaining the electrocatalytic material MTiO loaded with multi-metal titanium oxide on a titanium-based support. x @TM, where M represents a metallic element.

2. The method for preparing electrocatalytic materials of multi-metal titanium oxides supported on a titanium-based support according to claim 1, characterized in that, In step 1), the preprocessing operations are as follows: In air, a clean titanium-based support is placed between two layers of borohydride powder and annealed at 200-500 °C for 1-6 h to obtain a surface-activated and porous titanium-based support.

3. The method for preparing electrocatalytic materials of multi-metal titanium oxides supported on a titanium-based support according to claim 1, characterized in that, In step 2), the metal element in the metal precursor includes one or more of Ru, Ir, V, Fe, Co, Ni, Mn, Cu, Mo, Cr, Pr, Rh, Sn, W, Os, Pt, Pd, Pb, Re, Te, Zn, Hg, Ge, Nb, and Ta.

4. The method for preparing electrocatalytic materials of multi-metal titanium oxide supported on a titanium-based support according to claim 3, characterized in that, When there are one or two metallic elements, binary or ternary MTiO is formed. x Solid solution; when there are three or more metal elements, a medium / high entropy multimetallic titanium oxide catalytic layer is formed.

5. The method for preparing electrocatalytic materials of multi-metal titanium oxides supported on a titanium-based support according to claim 3, characterized in that, The specific steps for loading metal precursors onto the surface of a titanium-based substrate are as follows: The metal salt of the metal precursor is dissolved in a solvent to form a homogeneous multi-metal salt precursor solution. This multi-metal salt precursor solution is then uniformly loaded onto the surface of a titanium-based carrier by dropwise addition, impregnation, or spraying. The metal salt is a chloride, nitrate, sulfate, acetate, or organometallic salt. The solvent is a mixture of water and alcohol, with a volume ratio of water to alcohol of 1:(1-6).

6. The method for preparing electrocatalytic materials of multi-metal titanium oxide supported on a titanium-based support according to claim 1, characterized in that, In step 3), the drying process is carried out at 50-200 ℃ for 1-5 h; the annealing temperature is 400-700 ℃, the annealing time is 2-4 h, and the heating rate is 1-10 ℃·min. -1 .

7. An integrated multi-metal titanium oxide electrocatalytic electrode on a titanium-based support, characterized in that, The electrocatalytic electrode is prepared by the method for preparing a multi-metal titanium oxide supported on a titanium-based support according to any one of claims 1-6, characterized in that the electrocatalytic electrode comprises a titanium-based support and a multi-metal titanium oxide or high-entropy multi-metal titanium oxide catalytic layer grown in situ on its surface.

8. The integrated multi-metal titanium oxide electrocatalytic electrode on a titanium-based support according to claim 7, characterized in that, The electrocatalytic electrode is composed of densely distributed nanorods.

9. The application of the integrated multi-metal titanium oxide electrocatalytic electrode on a titanium-based support as described in claim 7 or 8 in electrochemical reactions, characterized in that, The electrocatalytic electrode is used as the anode and / or cathode electrode in acidic, alkaline, or neutral electrolytes, and is suitable for hydrogen evolution and / or oxygen evolution reactions in water splitting reactions, as well as oxygen reduction reactions and / or oxidation / reduction reactions of small organic molecules.

10. The application according to claim 9, characterized in that, When the electrocatalytic electrode is used as the working electrode, it reaches 10 mA cm⁻¹. -2 The oxygen production overpotential at current density reaches 248 mV, reaching 10 mA cm⁻¹. -2 The hydrogen production overpotential reaches 46 mV at the current density; this electrocatalytic electrode is suitable for electrocatalytic reactions at various pH values.

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