Ni Foam-Supported Ni Nanoclusters for Enhanced Electrocatalytic Oxygen Evolution Reaction

Developing oxygen evolution reaction (OER) electrocatalysts is essential to accomplish viable CO2 and water electrolysis. Herein, we report the fabrication and OER performance of Ni-foam (NF)-immobilized Ni-6 nanoclusters (NCs) (Ni-6/NF) prepared by a dip-coating process. The Ni-6/NF electrode exhibited a high current density of 500 mA/cm(2) for the OER at an overpotential as low as 0.39 V. Ni-6/NF exhibited high durability in an alkaline solution without corrosion. Electrokinetic studies revealed that OER can be easily initiated on Ni-6 NC with fast electron-transfer rates. Finally, we demonstrated stable CO2-to-CO electroreduction using an NC-based zero-gap CO2 electrolyzer operated at a current density of 100 mA/cm(2) and a full-cell potential of 2.0 V for 12 h.