A nickel and cobalt bimetal organic framework with high capacity as an anode material for lithium-ion batteries

摘要

Owing to the high controllability and regular pore structure, metal-organic frameworks (MOFs) have been considered as promising electrode materials. In this work, we report the synthesis of a nickel and cobalt 1,3,5-benzenetricarboxylate bimetal organic framework (Ni-Co-BTC) using a common solvothermal method, and investigate its electrochemical performance as an anode material for lithium-ion batteries. The Ni-Co-BTC anode shows a high specific capacity of 1242 mA h g(-1) at a current density of 200 mA g(-1) in the potential window of 0.01-3.0 V versus Li/Li+ along with excellent rate performance (384 mA h g(-1) at a current density of 4 A g(-1)), which could be ascribed to the conjugated carboxylates with a stronger pi-pi interaction and the synergistic effect of two cations. In addition, the mechanism of Li storage demonstrated that Li+ inserts into (or extracts from) the carboxylate groups and the benzene ring without the direct engagement of metal ions during galvanostatic charge-discharge measurements. More importantly, the Ni-Co-BTC MOF will be regarded as one of the promising anode materials for advanced Li storage.

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