Charge Redistribution in Co-Doped Nickel Sulfide to Accelerate Its Alcohol Electrooxidation

Electrochemical alcohol oxidation reaction (AOR) coupled with hydrogen evolution reaction is a significant way to coproduce green hydrogen and value-added chemicals with a low energy consumption. Herein, we report the synthesis of a series of M-doped (M = Co, Fe, and Cu) nickel sulfide nanowires (NWs), and the obtained Ni₂Co₁S₂ NWs exhibit high AOR performance. It shows a high benzyl alcohol oxidation activity of 56.8 mA/cm² at 1.35 V, which is 24.6 times as high as the activity for Ni₃S₂ NWs and also better than for most of the reported catalysts. The Ni₂Co₁S₂ NWs also show high activity for glycerol and ethylene glycol oxidations. The high AOR activity of Ni₂Co₁S₂ is attributed to the optimized charge redistribution induced by Co, which promotes the formation of the AOR active Ni(III) species. These results suggest the redistributed charge induced by foreign elements could significantly promote the catalytic performance, and the obtained catalysts are promising for AOR.