Ni-Mo2C hollow carbon nanospheres with enhanced performance as the cathode for lithium sulfur batteries

How to design the components of the cathode carrier is very important for the adsorption and catalysis of polysulfide conversion. Herein, Ni-Mo2C codoped hollow carbon nanospheres were prepared by two-step solvent synthesis and subsequent heat treatment. Ni as a supplementary material, it can effectively solve the problems of few electrochemical active sites and poor catalytic effect of lithium polysulfide (LPS) of Mo2C carbon nanospheres, and the optimal ratio of Ni to Mo2C was explored. Through the comparison of electrochemical tests, the Ni-Mo2C carbon nanospheres of optimal proportion shows high discharge specific capacity (0.2 C, 1101.3 mAh center dot g - 1) and excellent rate performance (2 C, 692.9 mAh center dot g - 1), which shows the best catalytic and adsorption effect on LPS. In addition, the optimal proportion of Ni-Mo2C carbon nanospheres has the highest lithium ion diffusion coefficient, which can accelerate the transport of Li+ and the kinetics of electrochemical reaction.