Nb-doped TiO₂ support with enhanced durability as a cathode for polymer electrolyte membrane fuel cells

Stability is one of the key requirements of electrocatalyst support materials for polymer electrolyte membrane fuel cells. To develop a highly stable Pt catalyst support material, in this work, we have synthesized Nb-doped TiO₂ electrocatalyst supports. The amount of Nb dopant is measured using inductively coupled plasma mass spectrometry, while the characteristics of the as-prepared Nb-doped TiO₂ supports are analyzed by transmission electron microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. Durability experiments are conducted by high potential cycling using the as-prepared Pt/TiO₂-Nb _x materials; half-cell cyclic voltammetry and single-cell performance measurements reveal that Pt/TiO₂-Nb₄ shows superior durability and corrosion resistance with a degradation rate of only 20% while the performance of commercial Pt/C support decreased 55%.