Synthesis of core-shell NiSe/C nanospheres as anodes for lithium and sodium storage

In this study, we design a facile strategy to synthesize the core-shell NiSe/C composites through a two-step method, in which the NiSe nanospheres were coated with a thin polydopamine layer by in-situ polymerization process and then calcined under inert atmosphere. When served as anodes for LIBs and SIBs, the core-shell NiSe/C composites can exhibit a superior cycling performance within 50 cycles and an excellent rate performance due to the synergistic effect between the core of NiSe nanospheres and the shell of robust carbon layer, which can effectively improve the conductivity of NiSe/C composites and accommodate volume and stress change during the cycling process.