Trimetallic (Co/Ni/Cu) Hydroxyphosphate Nanosheet Array as Efficient and Durable Electrocatalyst for Oxygen Evolution Reaction

The construction of earth-abundant and non-noble-metal-based oxygen evolution reaction (OER) electrocatalysts that could work effectively with long-term stability in alkaline electrolyte is of primary significance, but still challenging. Herein, we propose a novel OER electrocatalyst based on trimetallic (Co/Ni/Cu) hydroxyphosphate with unique nanosheet array architecture grown on nickel foam, aiming at designing the non-noble-metal-based OER electrocatalyst with both excellent durability and catalytic activity. The copper hydroxyphosphate was employed with a two-step hydrothermal/ion-exchange strategy for the fabrication of the target material. Serving as an OER electrocatalyst, the obtained trimetallic (Co/Ni/Cu) hydroxyphosphate/Ni foam composite demonstrates excellent electrocatalytic activity with an low overpotential of 370 mV at 50 mA/cm(2) (vs 523 mV of RuO2) and outstanding stability of 45 h (vs 8.5 h of RuO2) in 0.1 M KOH.