▎ 摘　　要

Preparation of a noble metal-graphene nanocomposite (MGN)-based clean and stable catalyst with uniform distribution of ultrafine nanoparticles can greatly improve the performance of fuel cells. Here, we show that surfactant-free MGNs for different noble metals can be prepared for high-performance fuel cell catalysis by the reaction of respective ultrasmall colloidal metal oxide/hydroxides with partially reduced colloidal graphene oxide. The resultant MGN is composed of highly dispersed M-M+n based nanoparticles of ultrasmall size and produces a strong and stable catalytic current for ethanol and formic acid oxidation.