Sonoelectrochemical fabrication of PDDA-RGO-PdPt nanocomposites as electrocatalyst for DAFCs

Sonoelectrochemical technique was successfully used to fabricate alloy-graphene nanocomposites. It not only provides a simple way to synthesize alloy nanoparticles, but also shows a general strategy for fabricating graphene-based nanostructures with anticipated properties. Pd was co-electrodeposited with Pt at different atomic ratios, and then was anchored with reduced graphene oxide (RGO) simultaneously in the presence of PDDA. The morphologies and structures of the as-prepared PDDA-RGO-PdPt nanocomposites were extensively investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The composition was evaluated by energy dispersive X-ray spectrometry (EDS) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Raman spectra revealed the surface properties of graphene and its interaction with metallic nanoparticles. Cyclic voltammetric (CV) and chronoamperometric experiments further exhibited their catalytic activity and stability for the electro-oxidation of ethanol in alkaline media, which could be applied as promising electrocatalysts for direct alcohol fuel cells (DAFCs).