ZIF-67/COF-derived highly dispersed Co3O4/N-doped porous carbon with excellent performance for oxygen evolution reaction and Li-ion batteries

摘要

Herein we report a facile bottom-up strategy to prepare highly dispersed supported Co3O4 on N-doped Porous Carbon (NPC). Specifically, ZIF-67 (ZIF = Zeolitic Imidazolate Frameworks) microcrystals firstly grow on benzoic acid modified covalent organic framework (BFC), resulting in ZIF-67/COF composite. Subsequently, highly dispersed Co3O4/NPC was obtained via the calcination of ZIF-67/COF. Interestingly, high dispersion of supported Co3O4 is dominated by homogeneous distribution of benzoic acid auchoring on nanoporous COF. More notably, largely triggered by the porosity and confining effect of COF, the resultant Co3O4/NPC features highly active crystal plane and a large specific surface area of 228.0 m(2)/g. Furthermore, the oxygen evolution reaction (OER) measurement results demonstrated that highly dispersed Co3O4/NPC features good catalytic activity (330 mV overpotential at 10 mA.cm(-2), 79 mV. dec(-1) Tafel slope and mass activity of 130 A.g(-1) at overpotential of 400 mV) and durable stability, superior to currently available counterparts. Moreover, Li-ion battery (LIB) tests also showed high reversible capacity (785 mA.h.g(-1) at 500 mA.g(-1)) as well as excellent cycling stability and rate performance. Furthermore, Density functional theory (DFT) calculation results demonstrated that these superior OER properties can be attributed to the geometrical and electronic effects of Co3O4/NPC on activation and adsorption/desorption of reaction species.