Influences of Mesopore Size on Oxygen Reduction Reaction Catalysis of Pt/Carbon Aerogels

A series of carbon aerogel (CA) samples with different pore sizes were loaded with platinum nanoparticles through the polyol reduction method. All the Pt/CAs possess nano Pt particles (2.5−3.5 nm) and uniform dispersion. The catalytic activities to oxygen reduction reaction (ORR) of Pt/CAs were evaluated by cyclic voltammetry in O2 saturated HClO4 with a rotating disk electrode. The catalytic activities of Pt/CAs are higher than that of commercial carbon black supported catalyst with the same Pt loading amount. Among the Pt/CAs, the relationship between ORR activity and mean meso pore size shows that the greater meso pore size can promote the catalysis activity. In the present study, the carbon aerogel with the mean meso pore size of 18.5 nm achieves the best ORR performance.