In Situ Copper Nanoparticles on Reduced Graphene Oxide (rGO/Cu) for Biphasic Hydrogen Evolution

Abstract Graphene‐based nanocomposites have attracted a tremendous attention, showing excellent performance in energy conversion applications, such as reduction of carbon dioxide and hydrogen evolution reaction (HER). Herein, a study on in situ generation Cu nanoparticles on reduced graphene oxide (rGO/Cu) by reducing simultaneously both graphene oxide and Cu 2+ ions during the biphasic HER by organic sacrificial agent decamethylferrocene (DMFc) was reported. The in situ‐generated rGO/Cu catalyst was morphologically and structurally characterized by microscopic and spectroscopic techniques, respectively. The hydrogen evolution catalytic activity of rGO/Cu was investigated by using 4‐electrode voltammetry and two‐phase reaction methods. rGO/Cu nanocomposite catalyst displayed a better catalytic activity than the non‐catalyzed reaction and free‐Cu catalyst by enhancing the HER rate approximately 208‐ and 3‐times, respectively. The HER activity of rGO/Cu gave results comparable to the noble metallic and the other nanocomposite catalysts such as Pt, Pd, MoS x and their nanocomposites with carbon‐based materials.