Palladium Nanoparticles Loaded on TiO2–Graphene Hybrids (Pd/TiO2–Gr) with Enhanced Electrocatalytic Activity in Formic Acid Oxidation

Abstract

We first report the hybrids of TiO2 and graphene (Gr) used as the support of Pd nanoparticles, showing high performance electrocatalysts for formic acid oxidation. The hybrids are prepared with the solvothermal method, and tetrabutyl titanate and graphene-oxide (GO) are used as the precursors. The initial mass ratios of Ti:GO in the precursors are 0.07, 0.15, 0.26, 0.60, respectively. Compared to Pd/graphene, the as-obtained Pd/TiO2–Gr electrocatalysts exhibit higher catalytic activity and stability. Among them, the Pd/TiO2–Gr (Ti : GO = 0.26, initial mass ratio) exhibit the highest activity. Its current density is about 3.1 times of Pd/graphene, and the agglomeration of Pd metal that can be seen in Pd/graphene has been inhibited in the as prepared Pd/TiO2–Gr. Thus the electrocatalytic performance of Pd for formic acid oxidation is greatly improved by the binary TiO2–graphene support.