Plasma-Engraved Lattice-Matched NiO/NiFeO Heterostructure with Ample Oxygen Vacancies for Efficient Water Electrolysis and Zn-Air Batteries.

Heterogeneous interface and defect engineering offer effective pathways to accelerate oxygen evolution reaction (OER) charge transfer kinetics and motivate optimal intrinsic catalytic activity. Herein, we report the lattice-matched NiO/NiFeO heterostructure with ample oxygen vacancies (Vo-NiO/NiFeO) induced by a feasible hydrothermal followed by calcination and plasma-engraving assistant technique, which shows the unique porous microflower arrangement of intertwined nanosheets. Benefitting from the synergetic effects between lattice-matched heterointerface and oxygen vacancies induce the strong electronic coupling, optimized OH/O diffusion pathway and ample active sites, thus-prepared Vo-NiO/NiFeO presents a favorable OER performance with a low overpotential (261 mV @ 10 mA cm) and small Tafel slope (39.