▎ 摘　　要

Polyol-free synthesis of highly loaded Pt catalysts on sulfuric-acid-treated graphene oxide (SGO) was reported. Sulfuric acid treatment increased the surface hydroxyl groups on graphene oxide (GO), which contributed to the reduction of Pt precursors in the absence of external reducing agent. By adjusting pH during the Pt reduction, we can get uniformly dispersed 2.5 nm size Pt nanoparticles on GO surface even at 50 wt% Pt loading amount. Cyclic voltammetry showed that increased pH resulted in increased electrochemical surface area.