Niobium-doped titanium dioxide on a functionalized carbon supported palladium catalyst for enhanced ethanol electro-oxidation

Abstract

Pd nanoparticles anchored on Nb-doped TiO2 with functionalized carbon support (denoted as Pd/Nb-TiO2-C) is synthesized through a controllable hydrolysis and impregnation method. The as-synthesized catalyst is characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Pd nanoparticles exhibit a uniform distribution with an average particle size of 3 nm. The electrochemical performance is tested by cyclic voltammetry (CV) and chronoamperometry (CA). Compared with Pd supported by functionalized carbon (Pd/C), Pd/Nb-TiO2-C demonstrates 15.7% higher metallic Pd content, 23% higher electrochemical active surface area, 75% higher current density in ethanol electro-oxidation, 5% higher durability, and better tolerance of carbonaceous species. The performance enhancement is attributed to the increased conductivity from Nb-doping and the synergistic effect between Pd and TiO2.