One-step synthesis of graphene-AuNPs by HMTA and the electrocatalytical application for O2 and H2O2

► HMTA is an environmentally friendly reducing and stabilizing agent. ► GO and Au precursor can be reduced to graphene-AuNPs nanocomposites by HMTA in one-step. ► The AuNPs are well-dispersed on graphene nanosheets in narrow size range. ► The graphene-AuNPs nanocomposites modified GCE showed excellent electrocatalytic activity toward O2 and H2O2.