Ru-doped Ta2O5 supported Pt nanoparticles: an efficient electrocatalyst for methanol oxidation

In this work, Ru-doped Ta 2 O 5 was firstly synthesized as support for Pt nanoparticles by calcination and chemical precipitation. The prepared Pt/Ru-Ta 2 O 5 catalysts were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). These characterization methods confirm that Pt nanoparticles were successfully supported on Ru-doped Ta 2 O 5 (Ru-Ta 2 O 5 ). The TEM reveals that Pt nanoparticles with an average diameter of ca. 4.0 ± 0.5 nm were uniformly distributed on the Ru-Ta 2 O 5 . The further electrochemical characterizations including cyclic voltammograms (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) methods show that Pt/Ru-Ta 2 O 5 catalysts have larger electrochemical surface area, better electrocatalytic activity, and higher stability toward the methanol oxidation reaction compared to the pure Ta 2 O 5 supported Pt catalysts. The excellent electrocatalytic performance is mainly contributed to the improvement of Ru for the dispersion of Pt nanoparticles, the increased conductivity of Ta 2 O 5 , as well as the promotion of oxidation reactivity by Ru. This work demonstrated that Ru-Ta 2 O 5 is a promising anode catalyst support for direct methanol fuel cells.