Enhanced Oxygen Evolution Reaction Performance on NiS x @Co 3 O 4 /Nickel Foam Electrocatalysts with Their Photothermal Property.

Based on the principle of heterogeneous catalysis for water electrolysis, electrocatalysts with appropriate electronic structure and photothermal property are expected to drive the oxygen evolution reaction effectively. Herein, amorphous NiS x -coupled nanourchin-like Co 3 O 4 was prepared on nickel foam (NiS x @Co 3 O 4 /NF) and investigated as a electrocatalyst for photothermal-assisted oxygen evolution reaction. The experimental investigations and simulant calculations jointly revealed NiS x @Co 3 O 4 /NF to be of suitable electronic structure and high near-infrared photothermal conversion capability to achieve the oxygen evolution reaction advantageously both in thermodynamics and in kinetics. Relative to Co 3 O 4 /NF and NiS x /NF, better oxygen evolution reaction activity, kinetics, and stability were achieved on NiS x @Co 3 O 4 /NF in 1.0 M KOH owing to the NiS x /Co 3 O 4 synergetic effect. In addition, the oxygen evolution reaction performance of NiS x @Co 3 O 4 /NF can be obviously enhanced under near-infrared light irradiation, since NiS x @Co 3 O 4 can absorb the near-infrared light to produce electric and thermal field. For the photothermal-mediated oxygen evolution reaction, the overpotential and Tafel slope of NiS x @Co 3 O 4 /NF at 50 mA cm -2 were reduced by 23 mV and 13 mV/dec, respectively. The present work provides an inspiring reference to design and develop photothermal-assisted water electrolysis using abundant solar energy.