Metal-organic framework cobalt gallate derived high-voltage carbon coated lithium cobalt oxide cathode and porous carbon supported cobalt oxide anode materials for superior lithium-ion storage

Exploring innovative green synthesis strategies for both cathode and anode materials with improved lithium-ion storage capabilities is of great importance in developing advanced lithium-ion batteries. In this work, a metal-organic framework (MOF) typed sample cobalt gallate (Co-GA), prepared by the direct redox coprecipitation reaction using gallic acid (GA) molecules and metallic cobalt (Co) foils in mild hydrothermal condition, is employed as a precursor for engineering electrode materials for lithium-ion batteries with high atomic efficiency and low environmental impact. Taking the advantages of the unique microstructure and chemical composition of MOF materials, the Co-GA precursor can be easily converted to a rod-like porous carbon framework confined cobalt oxide nanoparticle anode material (Co3O4/RPC) and a thin carbon layer coated nanosized lithium cobalt oxide (LiCoO2) cathode material (LCO/C), respectively, by simply changing the solid-state reaction conditions. In half-cells with metallic lithium as counter electrode, the LCO/C cathode delivers a stable reversible capacity of 189.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 128.61 mAh·g−1 after 800 cycles at 1000 mA·g−1 in the voltage range of 3.0–4.6 V, while the Co3O4/RPC anode shows a high reversible capacity of 1081.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 901.09 mAh·g−1 after 400 cycles at 1000 mA·g−1. This work provides a new perspective for green engineering of both anodic and cathodic materials with enhanced lithium-ion storage performances derived from MOF-typed precursors.