Combining Zn0.76Co0.24S with S-doped graphene as high-performance anode materials for lithium- and sodium-ion batteries

An easy and facile hydrothermal method is presented to synthesize hybrid materials of hollow mesoporous Zn Co S nanospheres anchored on reduced graphene oxide (rGO) sheets (Zn Co S@N/S-rGO), in which the obtained Zn Co S nanospheres are composed of numerous nanoparticles. Being evaluated as anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), the Zn Co S@N/S-rGO composites exhibited a high reversible capacity of 804 and 605 mA h g at the current density of 1 A g after 500 cycles for LIBs and SIBs, respectively. The excellent electrochemical performance of Zn Co S@N/S-rGO composites originates from the synergistic effect between hollow Zn Co S nanospheres and reduction graphene, as well as the void spaces between the neighbouring nanoparticles of Zn Co S providing large contact areas with electrolyte and buffer zone to accommodate the volume variation during the cycling process.