Preparation of NiSe2/CoSe2/C composites and their lithium storage properties

As an effective energy storage device, lithium-ion batteries (LIBs) have attracted great attention in the past 40 years because of their advantages of high energy density, long cycle life, light weight, and less environmental pollution, and people have put forward higher requirements for the performance of LIBs. The performance of LIBs depends largely on the choice of cathode and anode materials, while the anode materials are limited by their lithium intercalation mechanism, so they are difficult to greatly improve their specific capacity. In this work, NiSe2/CoSe2/C composites were prepared by calcining Ni-Co PBA and selenium powders in inert atmosphere at high temperature. The as-prepared samples are granular with a thin carbon layer on the surface. The average crystallite size of NiSe2/CoSe2/C-350 is 14.03 nm. The NiSe2/CoSe2/C-350 composites exhibit a high initial discharge specific capacity of 1381.5 mAh g(-1) at a current density of 0.1 A g(-1), and a reversible capacity of 695.3 mAh g(-1) after 200 cycles and remains at 425.3 mAh g(-1) after 800 cycles at a high current density of 1 A g(-1). Therefore, NiSe2/CoSe2/C-350 composites have a good development prospect as a new generation of anode materials for LIBs.

Automated summary

NiSe2/ CoSe2/C composites were prepared and exhibited excellent performance as anode materials for lithium-ion batteries, showing high initial discharge specific capacity and good cycle stability.