The nanosized Au particles supported by mesoporous carbon (MPC) and VXC-72R carbon black (CB) were prepared as catalyst for the direct oxidation of sodium borohydride, and labeled as Au/MPC and Au/CB, respectively. The structure and surface morphology of Au/MPC and Au/CB were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results showed that the nanosized Au particles had a face cubic structure and were uniformly distributed on the surfaces of the mesoporous carbon and VXC-72R carbon black. Besides, the size of the Au particles supported by the mesoporous carbon was about 16 nm, which was apparently less than that supported by the VXC-72R carbon black. The electrochemical properties of the samples were investigated by the cyclic voltammogram and linear potential sweeping. It was found that the peak current of oxidation on the Au/MPC electrode was 42.88 mA•cm^－2, which was 12.5% higher than that on the Au/CB electrode (38.10 mA•cm^－2).

Key words: direct borohydride fuel cell, anode catalyst, catalyst supporter, electrooxidation