Titanium-based platinum-nickel electrode materials, preparation methods, and applications thereof

Abstract

The present disclosure relates to the technical field of electrode materials and provides a titanium-based platinum-nickel electrode material, a preparation method, and an application thereof. The method includes: performing a first anodic oxidation and a second anodic oxidation sequentially on a titanium sheet in an ammonium fluoride solution to obtain an oxidized titanium sheet; performing calcination on the oxidized titanium sheet to obtain a titanium sheet containing a titanium dioxide layer; and performing electrodeposition on the titanium sheet containing the titanium dioxide layer in a platinum-based electrolyte to obtain the titanium-based platinum-nickel electrode material. The prepared titanium-based platinum-nickel electrode material effectively reduces the usage amount of Pt-based precious metals and can maintain high activity and stability to generate hydrogen peroxide on-line under the neutral condition; its cathode current density efficiency reaches 76.40%, the anode current density efficiency reaches 70.23%, and the bilayer capacitance value is 1.33 mF·cm−2, which is 4.2 times the bilayer capacitance value of the titanium-based platinum-nickel electrode material obtained without anodic oxidation, and has a very good industrial application prospect.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of electrode materials, and in particular, to titanium-based platinum-nickel electrode materials, preparation methods, and applications thereof.BACKGROUND

[0002] Hydrogen peroxide (H2O2), as a green fuel and an oxidizer, has attracted extensive attention in energy and environment-related fields in recent years. Currently, the industrial synthesis method of H2O2 involves an energy-intensive anthraquinone oxidation-reduction process. While this process is capable of generating large quantities of H2O2 at high concentrations, it also requires complex, large-scale equipment and generates large amounts of waste. Additionally, in most cases, the used concentration of H2O2 is low, which is typically less than 9 wt %. The electrochemical oxidation-reduction reaction (ORR) with a significant 2-electron (2e−) pathway is considered as a “green” pathway for the on-line generation of H2O2 compared to the anthraquinone oxidation-reduction process. The process produces H2O2 without any chemical waste output by inputting H2O, renewable electricity, and O2 in the air. However, during the reaction, O2 may be reduced to H2O through the 4-electron (4e−) ORR pathway (O2+4H++4e−→2H2O), or other side reactions may occur, thus reducing the production efficiency of H2O2. Accordingly, it is of great importance to design an ideal catalyst for the on-line synthesis of H2O2.SUMMARY

[0003] The purpose of the present disclosure is to overcome the existing problems in the prior art, and to provide titanium-based platinum-nickel electrode materials, preparation methods, and applications thereof.

[0004] In order to realize the above purpose, the present disclosure provides the following technical solution.

[0005] The present disclosure provides a preparing method for a titanium-based platinum-nickel electrode material, comprising:

[0006] (1) performing a first anodic oxidation and a second anodic oxidation sequentially on a titanium sheet in an ammonium fluoride solution to obtain an oxidized titanium sheet;

[0007] (2) performing calcination on the oxidized titanium sheet to obtain a titanium sheet containing a titanium dioxide layer; and

[0008] (3) performing electrodeposition on the titanium sheet containing the titanium dioxide layer in a platinum-based electrolyte to obtain the titanium-based platinum-nickel electrode material.

[0009] Preferably, in step (1), a solvent of the ammonium fluoride solution includes ethylene glycol and water; wherein a mass-volume-volume ratio of the ammonium fluoride, the ethylene glycol, and the water is (1-10) g:(100-1000) mL:(5-100) mL.

[0010] Preferably, in step (1), a voltage of the first anodic oxidation is within a range of 10-50 V and a time of the first anodic oxidation is within a range of 10-100 min.

[0011] Preferably, in step (2), a temperature of the calcination is within a range of 300-550° C., and a time of the calcination is within a range of 20-240 min.

[0012] Preferably, in step (3), the platinum-based electrolyte includes a platinum salt, a quaternary ammonium salt, and a hydrogen-bond donor; wherein the platinum salt is one or more of potassium chloroplatinate, potassium tetrachloroplatinate, platinum acetylacetonate, and chloroplatinic acid; the quaternary ammonium salt is one or more of choline chloride, tetramethylammonium chloride, and benzyltriethylammonium chloride; and the hydrogen-bond donor is ethylene glycol and / or propanetriol.

[0013] Preferably, a molar-volume ratio of the platinum salt and the hydrogen-bond donor is (1-10) mmol:(80-240) mL; and a molar ratio of the hydrogen-bond donor and the quaternary ammonium salt is (1-10):(1-5).

[0014] Preferably, an anode for the electrodeposition is nickel foam, nickel cloth, or nickel mesh; the electrodeposition is carried out at a temperature of 70-90° C., at a current of 0.005-0.1 A, and for a time of 10-120 min; and during a process of the electrodeposition, a relationship between a concentration of anodic dissolved nickel and time is represented as: C=C0+2kpt1 / 2; wherein Cis a concentration of dissolved nickel ions, which has a unit of mol / L; C0 is an initial concentration of dissolved nickel ions, which has a unit of mol / L; t is a reaction time, which has a unit of s; and kp is a reaction rate constant, which has a unit of mol·L−1·s−1 / 2.

[0015] Preferably, in step (3), a relationship between a current efficiency for anodic dissolution and an amount of dissolution in the process of the electrodeposition is represented as:ηa=m1I×q1×t×100⁢%;a relationship between a current efficiency for cathodic deposition and an amount of deposition is represented as:ηc=m2I×q1×t×100⁢%+m3I×q2×t×100⁢%;wherein ηa is the current efficiency for anodic dissolution, which has a unit of %; m1 is an amount of nickel produced by dissolution within a time t, which has a unit of g; l is a current of the electrolysis cell, which has a unit of A; q1 is an electrochemical equivalent of nickel, which is 1.042 g / (A·h); t is an electrolysis time, which has a unit of h; ηc is the current efficiency for cathodic deposition, which has a unit of %; m2 is an amount of nickel deposited within a time t, which has a unit of g; m3 is an amount of platinum deposited within a time t, which has a unit of g; q2 is an electrochemical equivalent of platinum, which is 0.867 g / (A·h).The present disclosure also provides a titanium-based platinum-nickel electrode material, which is prepared by the described method.The present disclosure also provides an application of the titanium-based platinum-nickel electrode material in the generating hydrogen peroxide.The beneficial effects of the present disclosure includes:(1) The present disclosure uses titanium sheets as a substrate material and performs the first anodic oxidation and the second anodic oxidation on the substrate material in the ammonium fluoride solution in sequence, which can expose more deposition sites for the subsequent electrodeposition process and increase the electrochemical specific surface area involved in the reaction, thus contributing to the enhancement of the selectivity of the 2e−ORR.

[0020] (2) The present disclosure prepares titanium-based platinum-nickel electrode materials by a simple and scalable constant-current electrodeposition process. In particular, nickel is gradually introduced by sacrificing a nickel anode, compared to the commonly used inert anode, a nickel source is provided and the electrodeposition process is regulated by introducing a nickel anode, thus significantly reducing the voltage required for the system (energy consumption). Moreover, the nickel anode itself participates in dissolution, which is expected to significantly reduce the decomposition of solvents in the electrodeposition system and the contamination of the inert anode at high potentials.

[0021] (3) The present disclosure uses a specific platinum-based electrolyte, which reduces the concentration of hydrogen atoms in the solution compared to the electrodeposition of metals in aqueous solutions, effectively avoiding the occurrence of hydrogen evolution reaction and hydrogen embrittlement, avoiding a decrease in aesthetics and mechanical properties of the plating layer.

[0022] (4) The titanium-based platinum-nickel electrode material prepared by the present disclosure not only effectively reduces the usage amount of Pt-based precious metal, but also can maintain high activity and stability to generate hydrogen peroxide on-line under the neutral condition, having a very good industrial application prospect.

[0023] (5) The titanium-based platinum-nickel electrode material prepared by the present disclosure has a cathode current density efficiency of 76.40%, an anode current density efficiency of 70.23%, and a bilayer capacitance value of 1.33 mF-cm−2, which is 4.2 times the bilayer capacitance value of the titanium-based platinum-nickel electrode material obtained without anodic oxidation.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a SEM image of an oxidized titanium sheet in Example 1;

[0025] FIG. 2 is a linear sweep voltammetry curve of a titanium-based platinum-nickel electrode material in Example 1;

[0026] FIG. 3 is a curve illustrating a relationship between the concentration of H2O2 generated by a titanium-based platinum-nickel electrode material under the neutral condition and time in Example 1;

[0027] FIG. 4 is a curve illustrating a relationship between a scan rate and a current density of titanium-based platinum-nickel electrode materials in Example 1 and Comparative Example 1.DETAILED DESCRIPTION

[0028] The present disclosure provides a preparing method for a titanium-based platinum-nickel electrode material, comprising:

[0029] (1) performing a first anodic oxidation and a second anodic oxidation sequentially on a titanium sheet in an ammonium fluoride solution to obtain an oxidized titanium sheet;

[0030] (2) performing calcination on the oxidized titanium sheet to obtain a titanium sheet containing a titanium dioxide layer; and

[0031] (3) performing electrodeposition on the titanium sheet containing the titanium dioxide layer in a platinum-based electrolyte to obtain the titanium-based platinum-nickel electrode material.

[0032] In the present disclosure, a material of the titanium sheet in step (1) is preferably TA0, TA1, TA2, TC4, or TC16.

[0033] In the present disclosure, the titanium sheet in step (1) is preferably pretreated before use, and the pretreatment includes the following steps: polishing the titanium sheet with metallographic sandpaper, placing the polished titanium sheet in acetone, hydrochloric acid, ethanol, and water in sequence for ultrasonic treatment, and finally drying the treated titanium sheet to complete the pretreatment of the titanium sheet.

[0034] In the present disclosure, the polishing includes a first polishing, a second polishing, and a third polishing carried out sequentially. The mesh number of the metallographic sandpaper for the first polishing is preferably 100-320 mesh, further preferably 150-280 mesh, and more preferably 180-240 mesh; the mesh number of the metallographic sandpaper for the second polishing is preferably 800-2000 mesh, further preferably 1000-1500 mesh, and more preferably 1200-1400 mesh; the mesh number of the metallographic sandpaper for the third polishing is preferably 2500-7000 mesh, further preferably 3000-5000 mesh, and more preferably 3500-4000 mesh.

[0035] In the present disclosure, a frequency of ultrasonic treatment of the polished titanium sheet in acetone, hydrochloric acid, ethanol, and deionized water is independently preferably 20-60 kHz, further preferably 30-50 kHz, more preferably 35-45 KHz; and a time of ultrasonic treatment of the titanium sheet in acetone, hydrochloric acid, ethanol, and deionized water is independently preferably is 30-210 min, further preferably 60-180 min, more preferably 80-120 min; a temperature of the drying is preferably 20-80° C., further preferably 30-60° C., more preferably 35-50° C.; and a the time of the drying is preferably 5-60 min, further preferably 10-50 min, more preferably 20-40 min.

[0036] In the present disclosure, a solvent of the ammonium fluoride solution in step (1) includes ethylene glycol and water; wherein a mass-volume-volume ratio of the ammonium fluoride, the ethylene glycol, and the water is preferably (1-10) g:(100-1000) mL:(5-100) mL, further preferably (2-9) g:(200-900) mL:(10-60) mL, more preferably (3-8) g:(300-800) mL:(15-50) mL.

[0037] In the present disclosure, a cathode of the first anodic oxidation in step (1) is graphite, a platinum sheet, or a titanium sheet; the graphite is a graphite rod or a graphite sheet; the first anodic oxidation is carried out in ammonium fluoride solution, and after completion, the obtained sample is placed in water for ultrasonic cleaning and drying, and after the drying, the sample is placed in the same ammonium fluoride solution (the same as that of the first anodic oxidation) for the second anodic oxidation; the cathode of the second anodic oxidation is graphite, a platinum sheet, or a titanium sheet; the graphite is graphite rod or graphite sheet; after the second anodic oxidation is completed, the obtained sample is subjected to water washing and then ethanol washing, and after the ethanol washing, secondary drying is carried out.

[0038] In the present disclosure, a voltage of the first anodic oxidation is preferably within a range of 10-50 V, further preferably within a range of 20-40 V, more preferably within a range of 25-35 V; a time of the first anodic oxidation is preferably within a range of 10-100 min, further preferably within a range of 20-90 min, more preferably within a range of 30-80 min.

[0039] In the present disclosure, after the first anodic oxidation is completed, a frequency of the ultrasonic cleaning is preferably within a range of 20-60 kHz, further preferably within a range of 30-50 kHz, more preferably within a range of 35-45 kHz; and a time of ultrasonic cleaning is preferably within a range of 10-90 min, further preferably within a range of 20-80 min, more preferably within a range of 30-60 min; a temperature of the drying is preferably within a range of 20-80° C., further preferably within a range of 30-60° C., more preferably within a range of 35-50° C.; and a time of the drying is preferably within a range of 5-60 min, further preferably within a range of 10-50 min, more preferably within a range of 20-40 min.

[0040] In the present disclosure, a voltage of the second anodic oxidation is preferably within a range of 10-50 V, further preferably within a range of 20-40 V, more preferably within a range of 25-35 V; and a time of the second anodic oxidation is preferably within a range of 10-120 min, further preferably within a range of 20-100 min, more preferably within a range of 30-90 min.

[0041] In the present disclosure, after the second anodic oxidation is completed, a temperature of the secondary drying is preferably within a range of 20-80° C., further preferably within a range of 30-60° C., more preferably within a range of 35-50° C.; and a time of the secondary drying is preferably within a range of 5-60 min, further preferably within a range of 10-50 min, more preferably within a range of 20-40 min.

[0042] In the present disclosure, a temperature of the calcination in step (2) is preferably within a range of 300-550° C., further preferably within a range of 350-500° C., more preferably within a range of 400-450° C.; a time of the calcination is preferably within a range of 20-240 min, further preferably within a range of 50-210 min, more preferably within a range of 80-180 min.

[0043] In the present disclosure, the platinum-based electrolyte in step (3) includes a platinum salt, a quaternary ammonium salt, and a hydrogen-bond donor; the platinum salt is one or more of potassium chloroplatinate, potassium tetrachloroplatinate, platinum acetylacetonate, and chloroplatinic acid; the quaternary ammonium salt is one or more of choline chloride, tetramethylammonium chloride, and benzyltriethylammonium chloride; and the hydrogen-bond donor is ethylene glycol and / or propanetriol.

[0044] In the present disclosure, a molar-volume ratio of the platinum salt and hydrogen-bond donor is preferably (1-10) mmol:(80-240) mL, further preferably (2-9) mmol:(100-220) mL, more preferably (3-8) mmol:(150-170) mL; the molar ratio of hydrogen-bond donor and quaternary ammonium salt is preferably (1-10):(1-5), further preferably (2-9):(2-4), more preferably (3-8):(2.5-3.5).

[0045] In the present disclosure, an anode for the electrodeposition in step (3) is nickel foam, nickel cloth, or nickel mesh; the electrodeposition is preferably carried out at a temperature of 70-90° C., further preferably 75-85° C., more preferably 77-83° C.; a current of the electrodeposition is preferably within a range of 0.005-0.1 A, further preferably within a range of 0.01-0.09 A, more preferably within a range of 0.03-0.07 A; a time of the electrodeposition is preferably within a range of 10-120 min, further preferably within a range of 20-110 min, more preferably within a range of 50-80 min.

[0046] In the present disclosure, during a process of the electrodeposition in step (3), a relationship between a concentration of anodic dissolved nickel and time is represented as: C=C0+2kpt1 / 2; wherein Cis a concentration of dissolved nickel ions, which has a unit of mol / L; C0 is an initial concentration of dissolved nickel ions, which has a unit of mol / L; t is a reaction time, which has a unit of s; and kp is a reaction rate constant, which has a unit of mol·L−1·s−1 / 2.

[0047] In the present disclosure, during a process of the electrodeposition in step (3), a relationship between a current efficiency for anodic dissolution and an amount of dissolution is represented as:ηa=m1I×q1×t×100⁢%;and a relationship between a current efficiency for cathodic deposition and an amount of deposition is represented as:ηc=m2I×q1×t×100⁢%+m3I×q2×t×100⁢%;wherein ηa is the current efficiency for anodic dissolution, which has a unit of %; m1 is an amount of nickel produced by dissolution within a time t, which has a unit of g; l is a current of the electrolysis cell, which has a unit of A; q1 is an electrochemical equivalent of nickel, which is 1.042 g / (A·h); tis an electrolysis time, which has a unit of h; ηc is the current efficiency for cathodic deposition, which has a unit of %; m2 is an amount of nickel deposited within a time t, which has a unit of g; ms is an amount of platinum deposited within a time t, which has a unit of g; q2 is an electrochemical equivalent of platinum, which is 0.867 g / (A·h).In the present disclosure, after the electrodeposition in step (3) is completed, the obtained sample is subjected to alcohol washing and water washing sequentially to obtain the titanium-based platinum-nickel electrode material; the alcohol washing and water washing can be accomplished according to the conventional technical means in the field, alcohol washing aims to clean the introduced organic reagents, and water washing aims to clean the inorganic ions on the surface of the electrode material.The present disclosure also provides a titanium-based platinum-nickel electrode material, which is prepared by the described method.The present disclosure also provides an application of the titanium-based platinum-nickel electrode material in generating hydrogen peroxide.

[0051] The technical solutions provided by the present disclosure are described in detail below in connection with the embodiments, which are not to be construed as limiting the scope of protection of the present disclosure.Example 1

[0052] The TA0 titanium sheet was sequentially polished with 200 mesh, 1200 mesh, and 4000 mesh metallographic sandpaper, and placed in acetone, hydrochloric acid, ethanol, and water for ultrasonic treatment (a frequency of the ultrasonic treatment was independently 40 kHz, and a time of the ultrasonic treatment was independently 120 min) and dried for 60 min at 25° C. to complete the pretreatment of the titanium sheet. 3 g of ammonium fluoride, 940 mL of ethylene glycol, and 60 mL of water were mixed to obtain an ammonium fluoride solution; the pretreated titanium sheet was placed in the ammonium fluoride solution for a first anodic oxidation, with a platinum sheet as a cathode, a voltage of 20 V and a time of 30 min, the obtained sample was placed in water for ultrasonic cleaning at a frequency of 40 KHz for 60 min, and dried at 25° C. for 40 min; after drying, the sample was placed in the same ammonium fluoride solution for a second anodic oxidation, with a platinum sheet as a cathode, a voltage of 20 V and a time of 90 min, after the second anodic oxidation is completed, the obtained sample was subjected to water washing and then ethanol washing, and dried at 25° C. for 30 min to obtain an oxidized titanium sheet; the oxidized titanium sheet was calcined at 450° C. for 90 min to obtain a titanium sheet containing a titanium dioxide layer. 4 mmol of potassium tetrachloroplatinate, 100 mL of ethylene glycol, and choline chloride (a molar ratio of ethylene glycol to choline chloride was 4:2) were mixed to obtain a platinum-based electrolyte. The nickel foam was used as an anode and the prepared titanium sheet containing a titanium dioxide layer was used as a cathode, electrodeposition was carried out for 60 min at a temperature of 80° C. and a current of 0.04 A, after the electrodeposition, the obtained sample was sequentially subjected to alcohol washing and water washing to obtain the titanium-based platinum-nickel electrode material.

[0053] The oxidized titanium sheet prepared in the Example was subjected to SEM characterization to obtain the SEM image of the oxidized titanium sheet, as shown in FIG. 1. As can be seen from FIG. 1, after the titanium sheet was anodized, each nanotube is compactly surrounded by 6-7 nearest nanotubes, indicating the formation of a more regular nanotube array structure on the surface, which is conducive to promoting the material transfer during the ORR process, providing a channel for the timely desorption of the H2O2 generated on-line, and avoiding the further reduction of H2O2 resulted from the blocked diffusion, thereby contributing to the enhancement of the selectivity of 2e− ORR.

[0054] The titanium-based platinum-nickel electrode material prepared in the Example was tested for electrochemical performance to obtain a linear sweep voltammetry curve of the titanium-based platinum-nickel electrode material, as shown in FIG. 2. As can be seen from FIG. 2, the titanium-based platinum-nickel electrode material has an onset potential of 0.673 V (vs. RHE), indicating that the electrode material had a higher 2e ORR activity.

[0055] The titanium-based platinum-nickel electrode material prepared in the Example was applied to the preparation of H2O2 to obtain a curve illustrating the relationship between the concentration of H2O2 generated by the titanium-based platinum-nickel electrode material under the neutral condition and time, as shown in FIG. 3. As can be seen from FIG. 3, the concentration of H2O2 increases with time. It is worth mentioning that 6.2 mg / L H2O2 is produced at 20 min using the titanium-based platinum-nickel electrode material prepared in the Example.

[0056] The titanium-based platinum-nickel electrode material prepared in the Example was tested for a current density efficiency, indicating that the titanium-based platinum-nickel electrode material has a cathode current density efficiency of 76.40% and an anode current density efficiency of 70.23%.Example 2

[0057] The TC4 titanium sheet was sequentially polished with 200 mesh, 1000 mesh, and 5000 mesh metallographic sandpaper, and placed in acetone, hydrochloric acid, ethanol, and water for ultrasonic treatment (a frequency of the ultrasonic treatment was independently of 50 kHz, and a time of the ultrasonic treatment was independently of 80 min), and dried for 30 min at 60° C. to complete the pretreatment of the titanium sheet. 6 g of ammonium fluoride, 950 mL of ethylene glycol, and 50 mL of water were mixed to obtain an ammonium fluoride solution; the pretreated titanium sheet was placed in the ammonium fluoride solution for a first anodic oxidation, with a graphite rod as a cathode, a voltage of 50 V, and a time of 60 min, the obtained sample was placed in water for ultrasonic cleaning at a frequency of 50 kHz for 30 min, and dried at 60° C. for 30 min; after the drying, the sample was placed in the same ammonium fluoride solution for a second anodic oxidation, with a graphite rod as a cathode, a voltage of 50 V, and a time of 90 min, after the second anodic oxidation is completed, the obtained sample was subjected to water washing and then ethanol washing, and dried at 60° C. for 20 min to obtain an oxidized titanium sheet; the oxidized titanium sheet was calcined at 400° C. for 120 min to obtain a titanium sheet containing a titanium dioxide layer. 3 mmol of platinum acetylacetonate, 100 mL of propanetriol, and choline chloride (a molar ratio of propanetriol to choline chloride was 3:2) were mixed to obtain a platinum-based electrolyte. The nickel foam was used as an anode and the prepared titanium sheet containing a titanium dioxide layer was used as a cathode, electrodeposition was carried out for 90 min at a temperature of 70° C. and a current of 0.05 A, after the electrodeposition, the obtained sample was sequentially subjected to alcohol washing and water washing to obtain a titanium-based platinum-nickel electrode material.

[0058] The titanium-based platinum-nickel electrode material prepared in the Example was tested for a current density efficiency, indicating that the titanium-based platinum-nickel electrode material has a cathode current density efficiency of 62.48% and an anode current density efficiency of 64.10%.Example 3

[0059] The TC16 titanium sheet was sequentially polished with 200 mesh, 1200 mesh, and 3000 mesh metallographic sandpaper, and placed in acetone, hydrochloric acid, ethanol, and water for ultrasonic treatment (a frequency of the ultrasonic treatment was independently 45 kHz, and a time of the ultrasonic treatment was independently 100 min), and dried at 55° C. for 40 min to complete the pretreatment of the titanium sheet. 6 g of ammonium fluoride, 900 mL of ethylene glycol, and 100 mL of water were mixed to obtain an ammonium fluoride solution; the pretreated titanium sheet was placed in the ammonium fluoride solution for a first anodic oxidation, with a graphite sheet as a cathode, a voltage of 30 V, and a time of 50 min, the obtained sample was placed in water for ultrasonic cleaning at a frequency of 45 kHz for 40 min, and dried at 55° C. for 30 min; after the drying, the sample was placed in the same ammonium fluoride solution for a second anodic oxidation, with a graphite sheet as a cathode, a voltage of 30V, and a time of 60 min, after second anodic oxidation is completed, the obtained sample was subjected to water washing and then ethanol washing, and dried at 55° C. for 30 min to obtain an oxidized titanium sheet; the oxidized titanium sheet was calcined at 350° C. for 150 min to obtain a titanium sheet containing a titanium dioxide layer. 7 mmol of potassium chloroplatinate, 150 mL of ethylene glycol, and tetramethylammonium chloride (a molar ratio of ethylene glycol to tetramethylammonium chloride was 4:3) were mixed to obtain a platinum-based electrolyte. The nickel mesh was used as an anode and the prepared titanium sheet containing a titanium dioxide layer was used as a cathode, electrodeposition was carried out for 80 min at a temperature of 85° C. and a current of 0.07 A, after the electrodeposition, the obtained sample was sequentially subjected to alcohol washing and water washing to obtain a titanium-based platinum-nickel electrode material.

[0060] The titanium-based platinum-nickel electrode material prepared in the Example was tested for a current density efficiency, indicating that the titanium-based platinum-nickel electrode material has a cathode current density efficiency of 73.18% and an anode current density efficiency of 69.58%.Comparative Example 1

[0061] The TA1 titanium sheet was sequentially polished with 200 mesh, 1200 mesh, and 4000 mesh metallographic sandpaper, and placed in acetone, hydrochloric acid, ethanol, and water for ultrasonication (a frequency of the ultrasonic treatment was independently 40 kHz, and a time of the ultrasonic treatment was independently 120 min) and dried at 25° C. for 40 min to complete the pretreatment of the titanium sheet. 4 mmol of potassium tetrachloroplatinate, 100 mL of ethylene glycol, and choline chloride (a molar ratio of ethylene glycol and choline chloride was 4:2) were mixed to obtain the platinum-based electrolyte. The nickel foam was used as an anode, and the pretreated titanium sheet was used as a cathode, electrodeposition was carried out for 60 min at a temperature of 80° C. and a current of 0.04 A, after the electrodeposition, the obtained sample was sequentially subjected to alcohol washing and water washing to obtain a titanium-based platinum-nickel electrode material.

[0062] The titanium-based platinum-nickel electrode material prepared in the Comparative Example was subjected to a current density efficiency test, indicating that the titanium-based platinum-nickel electrode material has a cathode current density efficiency of 49.75% and an anode current density efficiency of 53.02%.

[0063] The titanium-based platinum-nickel electrode material prepared in Example 1 (labeled as TiO2@PtNi) and the titanium-based platinum-nickel electrode material prepared in Comparative Example 1 (labeled as Ti@PtNi) were tested for electrochemical performance to obtain curves illustrating a relationship between a scan rate and current density of the titanium-based platinum-nickel electrode materials in Example 1 and the Comparative Example 1, as shown in FIG. 4. As can be seen in FIG. 4, a slope of the straight line is a bilayer capacitance value, and the electrochemical specific surface area is directly proportional to the bilayer capacitance value; the bilayer capacitance value of the obtained titanium-based platinum-nickel electrode material after anodic oxidation is 1.33 mF-cm−2, which is 4.2 times of the bilayer capacitance value of the obtained titanium-based platinum-nickel electrode material without anodic oxidation, illustrating that the obtained titanium-based platinum-nickel electrode material after anodic oxidation has a larger electrochemical specific surface area, which not only improves the mass transfer between the catalyst and the electrolyte, but also provides additional active sites that are favorable for the 2e ORR process.

[0064] As can be seen from the above Examples, the present disclosure provides the titanium-based platinum-nickel electrode material with a cathode current density efficiency of 76.40%, an anode current density efficiency of 70.23%, and a bilayer capacitance value of 1.33 mF-cm−2, which is 4.2 times of the bilayer capacitance value of the obtained titanium-based electrode material without anodic oxidation. The titanium-based platinum-nickel electrode material provided by the present disclosure not only effectively reduces the usage amount of Pt-based precious metal, but also can maintain high activity and stability to generate hydrogen peroxide on-line under the neutral condition, and has a very good industrial application prospect.

[0065] The foregoing is only a preferred embodiment of the present disclosure, and it should be pointed out that, for ordinary technicians in this technical field, a number of improvements and embellishments may be made without departing from the principles of the present disclosure, and the improvements and embellishments shall also be regarded as the protection scope of the present disclosure.

Claims

1. A preparing method for a titanium-based platinum-nickel electrode material, comprising:(1) performing a first anodic oxidation and a second anodic oxidation sequentially on a titanium sheet in an ammonium fluoride solution to obtain an oxidized titanium sheet;(2) performing calcination on the oxidized titanium sheet to obtain a titanium sheet containing a titanium dioxide layer; and(3) performing electrodeposition on the titanium sheet containing the titanium dioxide layer in a platinum-based electrolyte to obtain the titanium-based platinum-nickel electrode material.

2. The method of claim 1, wherein in step (1), a solvent of the ammonium fluoride solution comprises ethylene glycol and water; whereina mass-volume-volume ratio of the ammonium fluoride, the ethylene glycol, and the water is (1-10) g:(100-1000) mL:(5-100) mL.

3. The method of claim 1, wherein in step (1), a voltage of the first anodic oxidation is within a range of 10-50 V and a time of the first anodic oxidation is within a range of 10-100 min; and a voltage of the second anodic oxidation is within a range of 10-50 V and a time of the second anodic oxidation is within a range of 10-120 min.

4. The method of claim 1, wherein in step (2), a temperature of the calcination is within a range of 300-550° C., and a time of the calcination is within a range of 20-240 min.

5. The method of claim 1, wherein in step (3), the platinum-based electrolyte includes a platinum salt, a quaternary ammonium salt, and a hydrogen-bond donor; wherein the platinum salt is one or more of potassium chloroplatinate, potassium tetrachloroplatinate, platinum acetylacetonate, and chloroplatinic acid; the quaternary ammonium salt is one or more of choline chloride, tetramethylammonium chloride, and benzyltriethylammonium chloride; and the hydrogen-bond donor is ethylene glycol and / or propanetriol.

6. The method of claim 5, wherein a molar-volume ratio of the platinum salt and the hydrogen-bond donor is (1-10) mmol:(80-240) mL; and a molar ratio of the hydrogen-bond donor and the quaternary ammonium salt is (1-10):(1-5).

7. The method of claim 1, wherein in step (3), an anode for the electrodeposition is nickel foam, nickel cloth, or nickel mesh;the electrodeposition is carried out at a temperature of 70-90° C., at a current of 0.005-0.1 A, and for a time of 10-120 min; andduring a process of the electrodeposition, a relationship between a concentration of anodic dissolved nickel and time is represented as: C=C0+2kpt1 / 2;wherein C is a concentration of dissolved nickel ions, which has a unit of mol / L; C0 is an initial concentration of dissolved nickel ions, which has a unit of mol / L; t is a reaction time, which has a unit of s; and kp is a reaction rate constant, which has a unit of mol·L−1·s−1 / 2.

8. The method of claim 1, wherein in step (3), a relationship between a current efficiency for anodic dissolution and an amount of dissolution in the process of the electrodeposition is represented as:ηa=m1I×q1×t×100⁢%;and a relationship between a current efficiency for cathodic deposition and an amount of deposition is represented as:ηc=m2I×q1×t×100⁢%+m3I×q2×t×100⁢%;wherein ηa is the current efficiency for anodic dissolution, which has a unit of %; m1 is an amount of nickel produced by dissolution within a time t, which has a unit of g; l is a current of the electrolysis cell, which has a unit of A; q1 is an electrochemical equivalent of nickel, which is 1.042 g / (A·h); t is an electrolysis time, which has a unit of h; ηc is the current efficiency for cathodic deposition, which has a unit of %; m2 is an amount of nickel deposited within a time t, which has a unit of g; m3 is an amount of platinum deposited within a time t, which has a unit of g; q2 is an electrochemical equivalent of platinum, which is 0.867 g / (A·h).

9. A titanium-based platinum-nickel electrode material, which is prepared by the method of claim 1.

10. (canceled)

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