Engineering Interface and Oxygen Vacancies of NixCo1-xSe2 to Boost Oxygen Catalysis for Flexible Zn-Air Batteries.

Abstract

Exploring efficiently bifunctional oxygen electrocatalysts is the critical element for developing high power density metal-air batteries. Here, we propose an interface and oxygen vacancy engineering strategy to integrate subtle lattice distortions, oxygen vacancies and nanoporous on the surface of NixCo1-xSe2-O interface nanocrystals, which exhibit efficient bifunctional catalytic performances for oxygen evolution and reduction (OER and ORR). The results from X-ray absorption spectroscopy and electron spin resonance spectroscopy, demonstrate that the defect structure can enlarge the number of active sites for electrocatalytic performances. Flexible Zn-air battery using NixCo1-xSe2-O as cathode displays large specific capacity and remarkable stability even after twisting at any angles, thus promising for wearable and portable electronic device application. The implementation of our method provides a powerful strategy for preparing advanced catalysts for energy utilization.