Electrocatalytic Activity of PtAu Nanoparticles Deposited on TiO2 Nanotubes

We report on a facile photoassisted approach to directly deposit PtAu nanoparticles (NPs) with controllable compositions on TiO 2 nanotubes (TiO 2 NTs), which were synthesized by electrochemical anodization of Ti substrates. The fabricated TiO 2 NTs and TiO 2 -supported Pt and PtAu NPs were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The electrocatalytic activity of the TiO 2 NT supported, variably composed PtAu NPs was investigated by using cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). Our studies have shown that TiO 2 NT-supported PtAu nanoparticles with the Au composition between 30 and 50% exhibit very high electrocatalytic activity toward formic acid oxidation and that the direct dehydrogenation is the dominant reaction pathway in the electrochemical oxidation process.