Method for preparing carbon-loaded platinum electrocatalyst for fuel cell

Abstract

The invention provides a method for preparing a carbon-loaded platinum electrocatalyst for a fuel cell. The preparation method comprises the following steps of: dissolving a platinum precursor compound, a complexing agent and an auxiliary inorganic salt compound in water to form a solution, performing standing for a certain period of time, adding a reducing agent compound and a carbon carrier material, carrying out reaction for a certain period of time, and finally, carrying out subsequent treatment of filtering, washing and drying on the reacted system to obtain the carbon-loaded platinum electrocatalyst. According to the preparation method, the platinum nanoparticles newly generated by reaction can be stabilized, agglomeration of the generated platinum particles is effectively avoided, the loaded metal platinum particles are excellent in isotropic property, small in particle size and uniform in distribution, and the catalytic activity and stability can be effectively improved.

Description

technical field [0001] The invention relates to a method for preparing a catalyst, in particular to a method for preparing a carbon-loaded platinum electrocatalyst for a fuel cell. Background technique [0002] At present, the core active material of fuel cells is still relatively mature with carbon-supported platinum precious metals. The preparation of catalysts by chemical reduction is the most commonly used method at present. Including impregnation reduction method and polyol reduction method. The solid-phase impregnation reduction method is to firstly impregnate the platinum noble metal precursor and the carrier, dry and grind, and then reduce it with hydrogen in a tube furnace at high temperature (generally greater than 200°C). This method consumes a lot of energy and the noble metal is distributed on the carbon carrier. Inhomogeneous; the liquid phase impregnation reduction method is to first impregnate the noble metal precursor and carbon support, and then add a str...

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Problems solved by technology

The solid-phase impregnation reduction method is to firstly impregnate the platinum noble metal precursor and the carrier, dry and grind, and then reduce it with hydrogen in a tube furnace at high temperature (generally greater than 200°C). This method consumes a lot of energy and the noble metal is distributed on the carbon carrier. Inhomogeneous; the liquid phase impregnation reduction method is to first impregnate the noble metal precursor and carbon support, and then add a strong reducing agent to reduce at room temperature. Although this method is simple, fast and energy-free, the prepared electrocatalyst has a large particle size and Uneven diameter distribution

The most commonly used polyol reduction method is to use polyols such as ethylene glycol as a solvent and a reducing agent at the same time, heat (120-160°C) for 3-8 hours, and reduce the precious metal precursor to an electrocatalyst. Since the polyol also acts as a protective agent The electrocatalyst prepared by this method has a small particle size and is uniformly dispersed. Its disadvantages are high energy consumption, and polyhydric alcohols such as ethylene glycol are oxidized during the reaction process, which cannot be recycled, and the cost is high.

In addition, due to the anisotropy and large particle size of the platinum particles prepared by the above chemical reduction methods, they are easy to mature and grow during use, so the stability is poor and the catalytic activity is still not ideal.

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