To improve the electrode reaction speed of low-temperature fuel cells, the key is the cathode catalyst. Cathode catalyst must have the advantages of large surface areas, good stability, high activity, not easy to poison. Currently, most cathode catalysts of the fuel cells are mainly carbon with platinum (Pt / C) catalyst or platinum alloy catalyst. Direct methanol fuel cell (DMFC) has a serious problem - "methanol crossover", that is when methanol gets through the electrolyte membrane from the anode to enter into the cathode, since the reduction of oxygen and the oxidation of methanol are carried out simultaneously, and the intermediates from the oxidation of methanol make cathode catalyst poisoning, severely reducing the coulomb efficiency and the voltage efficiency of the battery.

 

The purpose of this method is to overcome the disadvantages of the prior art, to provide an oxygen reduction reaction (ORR) has a high selectivity and high catalytic activity, and a small amount of methanol in the presence, not only did not affect the reduction of oxygen, and even promote oxygen reduction of direct methanol fuel cell cathode catalyst. Here is a method to prepare the direct methanol fuel cell cathode catalyst described above, the preparation method is simple, with low cost and strong controllability.

 

The direct methanol fuel cell cathode catalyst, is a kind of tungsten bronze platinum-based compound catalyst, the basic structure formula is Pt-H_xWO₃ (0 <x≤l). Preparation method of this direct methanol fuel cell cathode catalyst has the following steps. (1)  dissolve chloroplatinic acid and sodium tungstate as the mole ratio of 1: 100~1: 20 in the sulfuric acid of 0.5~3molL acidity, dubbed uniform pale yellow sol; (2) the carbonaceous material is placed in the prepared sol in the range of any set -0.2~0.1V a potential value potentiostatic electrodeposition that prepared the basic structure of the formula Pt-H_xWO₃ platinum-based composite catalyst. Cathode catalyst prepared in this manner improves the catalytic activity of oxygen reduction, but also has good stability, so that the composite catalyst Pt-H_xWO₃ is a good fuel cell cathode catalyst. This method for preparing a catalyst deposition process is simple, easy to operate, easy to control, can be electrodeposited at room temperature, and therefore a lower cost of catalyst preparation.