Core-Shell NiO@Ni-P Hybrid Nanosheet Array for Synergistically Enhanced Oxygen Evolution Electrocatalysis: Experimental and Theoretical Insights.

Cost-effective and highly-efficient electrocatalysts for the oxygen evolution reaction are crucial for electrolytic hydrogen production. Here, we report core-shell NiO@Ni-P nanosheet arrays as a high-performance 3D catalyst for water oxidation electrocatalysis. Such nanoarrays demand overpotentials of 292 and 350 mV to drive geometrical catalytic current densities of 10 and 100 mA cm-2 , respectively, with an activity superior to its NiO and Ni-P counterparts. Notably, this catalyst also shows a high long-term electrochemical durability with a Faradaic efficiency of 98.1 %. Density functional theory calculation reveals that the superior activity benefits from the synergistic effect between NiO and Ni-P.