Design and synthesize hollow spindle Ni-doped Co9S8@ZnS composites and their enhanced cycle performance

Abstract Transition metal sulfides are considered as a kind of promising anode for lithium ion batteries due to their high theoretical capacity, but their further development are still greatly hampered by their volume expansion and electrical conductivity problems. Here, hollow spindle Ni-doped Co9S8@ZnS composites are synthesized by a simple two-steps hydrothermal method. The unique hollow structure, multi-component synergistic effect as well as effective ion doping can improve the comprehensive performance. When the as-obtained composites are used for the lithium ion batteries, which exhibit an ultra-long cycle performance. The capacity of 585 mAh/g can be maintained at 0.1 A/g after a long cycling of 1000 cycles. Even when the current density is raised to 1 A/g, the composites exhibit a high reversible discharge capacity of 758 mAh/g after 500 cycles.