Preparation and Electrochemical Activities of Pt–Ti Alloy PEFC Electrocatalysts

Abstract

Titanium is one of the most stable materials, remaining undissolved under strongly acidic polymer electrolyte fuel cell (PEFC) conditions. Nanocrystalline alloy electrocatalysts with a catalyst grain size of several nanometers have been successfully prepared by the colloidal and sol-gel method, characterized by X-ray diffraction, field-emission scanning electron microscope, scanning transmission electron microscope, energy-dispersive X-ray analysis, and X-ray photoelectron spectroscopy. Electrochemical activities were evaluated by current-voltage characteristics measurements using membrane electrode assemblies for humidified fuels with or without , cyclic voltammetry, and -stripping voltammetry in . alloy electrocatalysts exhibited higher electrochemical performance than pure Pt catalyst, i.e., higher activity for oxygen reduction reactions and improved tolerance.