Metal-Support Interaction of Pt Nanoparticles with Ionically and Non-Ionically Conductive Supports for CO Oxidation

Abstract

Platinum nanoparticles of narrow size distribution (∼2.5 nm) were synthesized using a modified polyol method and deposited on yttria-stabilized zirconia (Pt/YSZ), carbon (Pt/C) and γ-alumina (Pt/γ-Al2O3) supports, resulting in 1 wt % of Pt loading. Pt/YSZ has the highest catalytic activity toward CO oxidation among the studied catalysts. Decrease in the average particle size of Pt/YSZ led to the increase in CO conversion at low temperatures. Enhanced performances can be explained by the thermally induced O2− backspillover from YSZ over Pt nanoparticles in agreement with the electrochemical promotion mechanism. Observed effect becomes more pronounced with decreasing the particle size.