Highly Stable and Active Pt/Nb-TiO₂Carbon-Free Electrocatalyst for Proton Exchange Membrane Fuel Cells

Abstract

The current materials used in proton exchange membrane fuel cells (PEMFCs) are not sufficiently durable for commercial deployment. One of the major challenges lies in the development of an inexpensive, efficient, and highly durable and active electrocatalyst. Here a new type of carbon-free Pt/Nb-TiO 2 electrocatalyst has been reported. Mesoporous Nb-TiO 2 hollow spheres were synthesized by the sol-gel method using polystyrene (PS) sphere templates. Pt nanoparticles (NPs) were then deposited onto mesoporous Nb-TiO 2 hollow spheres via a simple wet-chemical route in aqueous solution, without the need for surfactants or potentiostats. The growth densities of Pt NPs on Nb-TiO 2 supports could be easily modulated by simply adjusting the experimental parameters. Electrochemical studies of Pt/Nb-TiO 2 show much enhanced activity and stability than commercial E-TEK Pt/C catalyst. PtNP/Nb-TiO 2 is a promising new cathode catalyst for PEMFC applications.