Pt/Ti catalyst prepared by simultaneous etching-displacement method and the electrocatalysis toward oxygen reduction reaction

Titanium supported Pt catalyst (Pt/Ti) is successfully prepared by a simultaneous etching-displacement method, in which the surface oxides on Ti particles is pre-etched by a home-made etching solution followed by a Pt deposition process via a displacement reaction of Pt precursor with newly exposed surface titanium atoms in the presence of etching reagents. In comparison with two carbon supported Pt (Pt/C) samples with different Pt particle sizes, the cyclic voltammetry of Pt/Ti shows a positive shift in the peak potential for surface oxide reduction, indicating a weakened oxygen adsorption. In accordance, the catalytic activity of Pt/Ti toward the oxygen reduction reaction (ORR) is remarkably improved in terms of both the surface activity and the mass activity. Pt/Ti also shows an improved catalytic activity toward the oxidative removal of adsorbed CO as revealed by an about 0.1 V negative shift in oxidation peak potential and a 0.3 V negative shift in the oxidation onset potential.

► Titanium supported Pt catalyst (Pt/Ti) prepared by an etching-displacement method. ► Weaker oxygen adsorption on Pt/Ti compared to Pt. ► The catalytic activity of Pt/Ti toward the ORR is remarkably high.