Pd-based Multi-metal Catalysts For Fuel Cells

In recent years,direct formic acid fuel cell(DFAFC)has received more and more attention because it has many advantages.Many efforts are on the improvements in the electrocatalytic performance of the catalysts of DFAFC.The electrocatalytic performance of the catalysts is mainly related to the component,structure and support of the catalyst.In this paper,we mainly study multi-element Pd based catalysts and catalysts with smaller amounts of Pd.These catalysts are applied to formic acid electrooxidation,ethanol electrooxidation and oxygen reduction reaction.The cyclic voltammetry(CV),linear sweeping curves(LSV)and chronoamperometric curves(CA)were used to measure the electrocatalytic activity and stability of the catalysts.Carbon loaded Pd-Cu-Fe catalysts(Pd-Cu-Fe/C)and Pd-NiCu/C catalysts(Pd-Ni-Cu/C)were fabricated with a novel strategy of partly etching carbon loaded tunable binary Cu-Fe alloy and Ni-Cu templates.They were applied to formic acid electrooxidation and ethanol electrooxidation,respectively.Catalysts started from the template of Cu7Fe3 template exhibit the highest catalytic activity and a high stability.The peak potential was 110 mV more negative than that of Pd/C catalyst.The peak potential was 48.3%higher than Pd/C.A series of Pd-Ni-Cu/C catalysts were used for the ethanol electrooxidation.The experiments indicated high performance for ethanol electrooxidation in alkaline solution.The onset potential of catalyst started from Ni8Cu2 template was 18 mV more negative than Pd/C catalyst.The Pd-Cu/C catalysts with smaller amounts of Pd were prepared by a sodium borohydride reduction method.The catalysts exhibit high catalytic performance for oxygen reduction reaction.The onset potential of Pd4Cu6/C was 26 mV more positive than Pd/C catalyst.