Boosting The Electrocatalytic Activity Of Hollow Nico Layered Double Hydroxides Nanocages Via A Self-Regulating Support Effect: A Highly Efficient Oxygen Electrode For Lithium-Oxygen Batteries

Surface engineering has been considered as one of the most useful strategies to enhance the activities of catalysts. However, conventional surface regulations usually require high cost and complicated chemical or physical processes, which restrict their practical applications. Herein, a zeolitic imidazolate framework-67 (ZIF-67) precursor is anchored first on Ni foam substrate, and then a hollow NiCo layered double hydroxides (NiCo-LDHs) nanocage is generated through a simple internal phase transition reaction. It is illustrated that with the selfregulating of Ni foam, more unsaturated metals sites and oxygen vacancy are created in the self-regulating NiCo-LDHs, which are key factors in improving the catalytic activities and durability. The self-regulating NiCo-LDHs electrode is used as cathode in nonaqueous lithium-oxygen (Li-O-2) battery, and the battery exhibits a high initial capacity (26853 mAh center dot g@200 mA center dot g(-1)), high rate capability (upto 2000 mA center dot g(-1)), low overpotential (1.07 V), and long cycle life (upto 500 h). This work opens a facile direction to fabricate highly efficient electrocatalytic material through optimizing the electrode support effect.