Cobalt-doped TaOCl3 nanoparticles/carbon compounds with advanced specific capacity for lithium-ion batteries

Transition metal oxychlorides, such as VOCl and BiOCl, have become an attractive candidate material for lithium-ion batteries (LIBs). In this paper, the TaOCl3/Co-CNT was obtained by a non-hydrosol gel method, which used for lithium-ion anode materials. Pure TaOCl3 possesses a higher theoretical capacity, but the expected effect would not be obtained due to the volume expansion. The introduction of Co-CNT enhances the stability of the structure, shortens the Li+ transmission distance, and introduces conductive metal cobalt, which improves the electrochemical performance of the electrode material. TaOCl3/Co-CNT, as the anode electrode, exhibits superb electrochemical properties, including a high reversible specific capacity of 1295 mA h g−1 at 100 mA g−1, the perfect cycle stability (the capacity of TaOCl3/Co-CNT electrode achieved 650 mA h g−1 at 500 mA g−1 after 200 cycles) and the excellent rate performance. The results confirm that this product combined with facile fabrication process is promising for the practical applications in LIBs.