Co-Mo microcolumns decorated with trace Pt for large current density hydrogen generation in alkaline seawater

Electrolysis in seawater is cost-saving but challenging approach for hydrogen production. In this study, self-supported anticaustic three dimensional (3D) microcolumns anchored with trace Pt clusters on nickel foam (NF) is prepared through solvothermal followed by thermal reduction procedures (Pt-Co-Mo). The as-synthesized electrode owns superhydrophilic and aerophilic surface which favors close contact between the electrode and electrolyte and release of the generated hydrogen bubbles. Besides, the strong synergistic effect between Pt and matrix lead to a significantly improved HER intrinsic activity. Thanks to the above merits, the self-supported Pt-Co-Mo electrode presents outstanding HER activity, which only requires an extremely low overpotentials of 179.2 mV and 194.1 mV to reach a large current density of 2000 mA cm−2 in 1 M KOH and 1 M KOH seawater, respectively. For overall water splitting, cell voltages down to 1.50 V and 1.51 V are necessary to drive 10 mA cm−2 in 1 M KOH and alkaline seawater, respectively.