▎ 摘　　要

Graphene is attracting a lot of researchers due to its diversified applications in various fields. However, till now there is no report about the usage of graphene as an electrocatalyst for catalyzing electrochemical Hydrogen Evolution Reaction (HER) in a water electrolyzer. Here, we demonstrate that chemically Reduced Graphene Oxide (rGO) exhibits hydrogen evolution activity close to that of 20 wt.% Pt/C in an acid electrolyte when it is subjected to electrochemical cycling in the potential window -180 to + 420 mV vs. RHE. rGO exhibits an increase in the HER activity after cyclic voltammetry (CV) activation, provided Platinum (Pt) is used as the Counter Electrode (C.E). When pure graphite rod is employed as a C.E, unfortunately, the HER activity on rGO is negligible. When Pt is used as the C.E, Pt dissolves from the Pt C.E and subsequently deposites on the rGO material coated onto the Working Electrode (W.E). Transmission Electron Microscopy (TEM) analysis indicates that the deposited particles remain as Pt Nanoparticles (Nps) on the surface of the rGO material. Possibly, improved activity is achieved due to the presence of Pt Nps on the surface of the rGO material rather than the activation of the rGO material itself.