Preparation And Performance Of New Electrocatalysts For Oxygen Reduction Reaction (ORR)

Electrocatalyst is the key materials of Fuel Cells, currently cathode oxygen reduction and anode CO tolerant catalysts mainly Pt/C and PtRu/C, respectively. However, the high costs of such catalysts, restraining the commercialization of fuel cell one of the important factors. Thus, we have chosen cathode catalysts for oxygen reduction as a research and development -- a new type of high-performance catalysts, using rotating disk electrode techniques to research mechanism of oxygen reduction.Catalyst (Pt-NbPOx)/MWCNTs were prepared by using a simple microwave irradiation route on multi-walled carbon nanotubes (MWCNTs). The (Pt-NbPOx)/MWCNTs catalyst was characterized by CV, LSV and Tafel electrochemistry method. The results were indicated that 10wt %NbPOx was the best loading in terms of current density. Compared liquid reduction to microwave reduction prepared Pt-FePOx/MWCNTs; electrochemical results indicated that the latter exhibited better electrocatalytic. It was proved that microwave reduction was a better method to synthesis nano-composite.Pt-M/MWCNTs (M=Au, Ag) was prepared by intermittent microwave heat reduction method. Results indicated that Pt: Au mass ration of 1:2 exhibited the highest catalytic activity for oxygen reduction. Alloy method was an effiency way to improve the catalytic of Pt-based catalyst. Pt-Ag/MWCNTs catalyst was modified by cyclic voltammetric (CV) method. The modified catalyst lowered overpotential of oxygen reduction reaction.Hydrothermal prepared Ag-MoO3 and Ag-WO3 were firstly used as electrocatalyt for oxygen reduction. Composite catalysts can promote the dissociation and adsobtion of O2 molecule, improved the catalytic of oxygen reduction reaction.