Deactivated-desulfurizer-derived hollow copper sulfide as anode materials for advanced sodium ion batteries

Zinc oxide is widely used in industry due to its excellent desulfurization effect, but the green recycling of waste desulfurizer is facing huge challenges. In this research, we firstly introduced the ion exchange process to transform ZnS deactivated desulfurizers to hollow CuS electrode materials which have excellent energy storage performance as anode materials for sodium ion batteries: its initial charge specific capacity is 418.6 mAh g−1 at the current density of 100 mA g−1with the first coulomb efficiency of 91.6%. After 100 cycles, the charge capacity of copper sulfide still maintains 86.4% due to the formation of NaxCuS intermediate product. In rate performance test, the reversible capacity can reach 246.4 mAh g−1 at 5 A g−1. In addition, Zn2+ after ion exchange can transform into Zinc oxide for recycling. This research not only fundamentally solves the problem of zinc oxide adsorbent regeneration, but also provides a high-performance anode material for sodium ion batteries to achieve the high value-added recycle and application of waste desulfurizer.