Fiber-like nanostructured Ti4O7 used as durable fuel cell catalyst support in oxygen reduction catalysis

Abstract

We report on the successful synthesis of fiber-like nanostructured Ti₄O₇ (NS-Ti₄O₇) by multistep method. The specific surface area of this NS-Ti₄O₇ was 26 m² g⁻¹. The synthesized NS-Ti₄O₇ was platinized and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray photoelectron spectroscopy (XPS) and electrochemical testing. It was found that the monodispersed Pt nanoparticles supported on NS-Ti₄O₇ with a uniform size of 4.8 nm. The prepared Pt/NS-Ti₄O₇ catalysts exhibited superior durability as well as enhanced Pt mass activity in comparison to commercial Pt/XC-72 catalyst. After undergoing accelerated durability tests (ADT), the oxygen reduction reaction (ORR) mass activity of Pt/NS-Ti₄O₇ was nearly thirty times higher than that of Pt/XC-72. The superior durability of Pt/NS-Ti₄O₇ is attributed to the high stability of Ti₄O₇ and the strong metal–support interaction between Pt and Ti₄O₇.