阅读说明：本技术 一种燃料电池双元合金催化剂的微波制备方法 (Microwave preparation method of fuel cell binary alloy catalyst ) 是由 华秋茹 张义煌 张明 刘倩 包喆宇 陈杰 李刚 于 2020-05-15 设计创作，主要内容包括：本发明属于燃料电池技术领域,特别涉及到一种燃料电池双元合金催化剂的微波制备方法。本发明的制备方法包括前驱体悬浮液配制过程、微波反应过程、催化剂酸洗处理过程,利用添加剂和微波同步还原铂与过渡金属,一步合成双元合金催化剂,可以在较低温度焙烧甚至省去焙烧过程,从而有效抑制合金颗粒的长大；微波还原后进行酸洗可以除去未合金化的过渡金属元素,工艺、设备简单,合成周期短,易于实现工业化生产；使用过渡金属与铂制备双元合金催化剂,降低了贵金属铂的用量,能够有效降低催化剂的成本,制备出的催化剂合金化程度良好,元素比例与颗粒粒径可控,催化活性及稳定性高。(The invention belongs to the technical field of fuel cells, and particularly relates to a microwave preparation method of a fuel cell binary alloy catalyst. The preparation method comprises a precursor suspension liquid preparation process, a microwave reaction process and a catalyst acid pickling treatment process, wherein the additive and microwave are used for synchronously reducing platinum and transition metal, so that the binary alloy catalyst is synthesized in one step, and can be roasted at a lower temperature, even the roasting process is omitted, and the growth of alloy particles is effectively inhibited; the non-alloyed transition metal elements can be removed by acid washing after microwave reduction, the process and equipment are simple, the synthesis period is short, and the industrial production is easy to realize; the binary alloy catalyst prepared from the transition metal and the platinum reduces the using amount of the noble metal platinum, can effectively reduce the cost of the catalyst, and has the advantages of good alloying degree, controllable element proportion and particle size, high catalytic activity and stability.)

1. A microwave preparation method of a fuel cell binary alloy catalyst is characterized by comprising the following steps:

(1) dispersing a carbon carrier, a platinum-containing compound solution and a transition metal salt solution in ethylene glycol, and performing ultrasonic dispersion or stirring dispersion to obtain a binary precursor suspension;

(2) adding an additive and a precipitator into the binary precursor suspension prepared in the step (1), stirring, heating in a microwave oven to boil, cooling to room temperature, and standing for 0.1-24 h;

(3) adding an acid solution into the mixed solution obtained in the step (2), standing for 0.1-100h, then carrying out centrifugal washing or filter pressing washing, and carrying out forced air drying at 30-90 ℃ to obtain a binary alloy catalyst;

or centrifugally washing or filter-pressing washing the mixed solution in the step (2), blowing and drying at 30-90 ℃, then putting into a tubular furnace, roasting at 100-500 ℃ in a protective atmosphere for 0.5-6h, then adding an acid solution, standing for 0.1-100h, then centrifugally washing or filter-pressing washing again, and blowing and drying at 30-90 ℃ to obtain the binary alloy catalyst.

2. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the platinum-containing compound comprises one or more of chloroplatinic acid, potassium chloroplatinate, platinum chloride and dinitroso diammine platinum, and the concentration of the platinum-containing compound solution is 0.5-800 g/L.

3. The microwave preparation method of a fuel cell binary alloy catalyst as claimed in claim 1, wherein the transition metal salt is a soluble salt of cobalt, nickel or copper, including cobalt nitrate, cobalt chloride, cobalt sulfate, nickel nitrate or copper sulfate, and the concentration of the transition metal salt is 0.1-500 g/L.

4. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the solvent in the platinum compound-containing solution or/and the transition metal salt solution is ethylene glycol and/or water, and the ratio of the amount of water to the amount of ethylene glycol is 0-100: 1.

5. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the precipitant is one or more of sodium hydroxide, ammonia water or sodium carbonate, and the molar ratio of the precipitant to the transition metal is controlled to be 0.1-120: 1.

6. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the additive is one or more of sodium hypophosphite, sodium formate, sodium sulfite, citric acid or ethylene diamine tetraacetic acid, and the molar ratio of the additive to the transition metal is 0-200: 1.

7. The microwave preparation method of the fuel cell binary alloy catalyst as claimed in claim 1, wherein the power of the microwave oven in step (2) is 100-9000W, and the heating time is 1-120 min.

8. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the acid solution in the step (3) is one or more of hydrochloric acid, sulfuric acid or nitric acid, the concentration range is 0.01-18.4mol/L, and the addition amount is 2-5000 mL.

9. The microwave preparation method of the fuel cell binary alloy catalyst according to claim 1, wherein the introduced shielding gas during the calcination in the step (3) is one or more of nitrogen, argon and hydrogen.

Technical Field

The invention belongs to the technical field of fuel cells, and particularly relates to a microwave preparation method of a fuel cell binary alloy catalyst.

Background

The fuel cell technology has wide application, can be applied to industries such as automobiles, aviation, energy storage, power generation, ships and the like, wherein the proton exchange membrane fuel cell has the advantages of high energy efficiency, environmental friendliness, high starting speed, safe and reliable operation and the like, and is always a hotspot of research. The cost and performance of the catalyst directly affect the cost and performance of the fuel cell, so the task of developing a high-performance and low-cost catalyst is urgent.

Due to the high difficulty in preparing the multi-element alloy catalyst, the difficult control of element proportion and the high industrialization difficulty, the research on the binary alloy catalyst such as platinum cobalt, platinum nickel, platinum palladium and the like has more industrial significance. In the process of preparing the platinum-palladium catalyst in the patent CN105642309A, the platinum-based catalyst is used, and then the palladium element is added and roasted at the high temperature of 700 ℃ and 1000 ℃ to alloy the platinum-palladium catalyst, so that the energy consumption is large and the industrial amplification is difficult. In the existing preparation method of the binary alloy catalyst, most of the binary alloy catalysts need to be prepared in advance, and another element is added for high-temperature roasting to form the binary alloy, so that the preparation method has the disadvantages of multiple preparation steps, complex device, difficult control of particle size, large energy consumption and high cost.

Disclosure of Invention

The invention aims to provide a microwave preparation method of a fuel cell binary alloy catalyst. The preparation method can synchronously reduce the platinum and the cobalt elements to form the fuel cell binary alloy catalyst in one step, can effectively reduce the consumption of noble metals of the fuel cell, reduce the cost and improve the catalytic activity and stability of oxygen reduction.

In order to solve the technical problems, the invention adopts the following technical scheme: a microwave preparation method of a fuel cell binary alloy catalyst comprises the following steps:

(1) dispersing a carbon carrier, a platinum-containing compound solution and a transition metal salt solution in ethylene glycol, and performing ultrasonic dispersion or stirring dispersion to obtain a binary precursor suspension;

(2) adding an additive and a precipitator into the binary precursor suspension prepared in the step (1), stirring, heating in a microwave oven to boil, cooling to room temperature, and standing for 0.1-24 h;

(3) adding an acid solution into the mixed solution obtained in the step (2), standing for 0.1-100h, then carrying out centrifugal washing or filter pressing washing, and carrying out forced air drying at 30-90 ℃ to obtain a binary alloy catalyst;

or centrifugally washing or filter-pressing washing the mixed solution in the step (2), blowing and drying at 30-90 ℃, then putting into a tubular furnace, roasting at 100-500 ℃ in a protective atmosphere for 0.5-6h, then adding an acid solution, standing for 0.1-100h, then centrifugally washing or filter-pressing washing again, and blowing and drying at 30-90 ℃ to obtain the binary alloy catalyst.

The platinum-containing compound comprises one or more of chloroplatinic acid, potassium chloroplatinate, platinum chloride and dinitroso diammineplatinum, and the concentration of the platinum-containing compound solution is 0.5-800 g/L.

The transition metal salt is soluble salt of cobalt, nickel or copper, and comprises cobalt nitrate, cobalt chloride, cobalt sulfate, nickel nitrate or copper sulfate, and the concentration of the transition metal salt is 0.1-500 g/L.

The solvent in the platinum-containing compound solution or/and the transition metal salt solution is glycol and/or water, and the ratio of the water to the glycol is 0-100: 1.

The precipitant is one or more of sodium hydroxide, ammonia water or sodium carbonate, and the molar ratio of the precipitant to the transition metal is controlled to be 0.1-120: 1.

The additive is one or more of sodium hypophosphite, sodium formate, sodium sulfite, citric acid or ethylene diamine tetraacetic acid, and the molar ratio of the additive to the transition metal is 0-200: 1.

The power of the microwave oven in the step (2) is 100-9000W, and the heating time is 1-120 min.

The acid solution in the step (3) is one or more of hydrochloric acid, sulfuric acid or nitric acid, the concentration range is 0.01-18.4mol/L, and the adding amount is 2-5000 mL.

And (3) introducing protective gas during roasting, wherein the protective gas is one or more of nitrogen, argon and hydrogen.

Compared with the prior art, the invention has the following advantages:

1. the preparation method of the binary alloy catalyst utilizes the additive and the microwave to synchronously reduce the platinum and the transition metal, synthesizes the binary alloy catalyst in one step, has simple process and equipment, short synthesis period and is easy to realize industrial production.

2. The invention uses transition metal and platinum element to prepare the binary alloy catalyst, reduces the dosage of noble metal platinum and effectively reduces the cost of the catalyst.

3. The invention adopts the microwave preparation process to accelerate and promote the reduction of platinum and transition metal, and the alloy catalyst is formed in one step, so that the roasting process can be saved even at a lower temperature, thereby effectively inhibiting the growth of alloy particles; the non-alloyed transition metal elements can be removed by acid washing after microwave reduction.

4. The catalyst prepared by the preparation method has good alloying degree, controllable element proportion and particle size, and high catalytic activity and stability.

Drawings

FIG. 1 is a flow chart of the preparation of the binary alloy catalyst of the present invention.

Figure 2 is a comparison of XRD patterns of catalysts prepared in examples 1-4 of the present invention.

FIG. 3 is a cyclic voltammogram of the catalysts prepared in examples 5 and 6 of the present invention.

FIG. 4 is an oxygen reduction contrast curve of the catalyst prepared in example 7 of the present invention versus a commercial catalyst.

Detailed Description

The following detailed description of the invention refers to the accompanying drawings.