Morphology-Controlled Synthesis of Palladium Nanostructures by Sonoelectrochemical Method and Their Application in Direct Alcohol Oxidation

A simple sonoelectrochemical method was used to realize the morphology-control led synthesis of palladium nanostructures at room temperature. The palladium spherical nanoparticles, multitwinned particles, and spherical spongelike particles (SSPs) were successfully prepared in the presence of different surfactants or polymers. It was found that the size and shape of the Pd nanostructures could be controlled by varying current density and pH value of the precursor solution. The Pd nanostructures were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, field emission scanning electron microscopy, energy-dispersive X-ray, and X-ray diffraction. The possible formation mechanism was discussed. In addition, the electrocatalytic properties of the Pd nanostructures for direct alcohol oxidation in alkaline media were systematically investigated. The results showed that SSPs had a higher electrochemical active surface and result in more stable and better electrocatalytic properties than other Pd nanostructures for the ethanol electrooxidation.