An ultrasonic assisted electrochemical method was used for the shape-controlled synthesis of platinum electrocatalysts at room temperature. The 3D platinum cubic spongelike particles, branched particles and spherical porous particles were prepared with or without shape controlling agents, such as polyvinyl pyrrolidone (PVP) and cetyltrimethyl ammonium chloride (CTAC), respectively. The transmission electron microscopy, X-ray diffraction and electrochemical measurements showed that the morphology, microstructure and electrocatalytic activities of these platinum electrocatalysts could be changed by shape control agent. In addition, the electrocatalytic properties of these platinum electrocatalysts for oxygen reduction reaction and methanol oxidation reaction were systematically investigated. The results showed that spherical porous particles had a higher electrochemical active surface, which resulted in the better and more stable electrocatalytic properties than other 3D platinum electrocatalysts.

Key words: electrochemistry, sonochemistry, shape-control, platinum electrocatalyst, 3D nanostructure