Novel metal-organic anode material by in-situ chelating Ni2+ with tannic acid on carbon nanotube for high-performance Li storage

Lithium-ion batteries (LIBs) with natural organic anode are attracting intensive interest for application owing to their structural diversity, cost-effectiveness, eco-friendliness, and high specific capacity. However, directly usage of natural organic materials as anode materials usually encounters poor electrochemical properties such as low reversible capacity and short cycling life. Thus, developing high-performance organic electrode materials for LIBs remains a great challenge. Herein, we present a rational design and fabrication of TA-Ni@CNTs by in-situ coating TA-Ni polymers onto the surface of carbon nanotubes (CNTs) as a superior anode material for LIBs. Specifically, the highly conductive CNTs can effectively relieve the aggregation of TA-Ni and improve the electronic conductivity. Meanwhile, the strong chelation among nickel irons and catechol groups enhances the structure stability and inhibits the dissolving property. Consequently, as an anode material for LIBs, the resulting TA-Ni@CNTs achieves a high reversible capacity of 1418.8 mAh·g−1 at 0.1 A·g−1 after 216 cycles and an outstanding cycling stability with 951.1 mAh·g−1 at 0.5 A·g−1 after 323 cycles. The presented design strategy holds great promise for developing more-efficient electrode materials for LIBs.