Intimately coupled WS2 nanosheets in hierarchical hollow carbon nanospheres as the high-performance anode material for lithium-ion storage

Lithium-ion hybrid capacitors (LIHCs) have drawn extensive attention in field of energy storage. However, the absence of appropriate electrode materials with rapid kinetics restricted the overall performance of the capacitors. Herein, hierarchical N, P-codoped hollow carbon nanospheres coupling with WS2 nanosheets (N, P-codoped HCNS/WS2 NSs) were fabricated for boosting lithium storage materials. Specially, the WS2 nanosheets with several layers embedded in the N, P-codoped hollow carbon nanospheres could not only enhance the conductivity of composites, but also provide abundant channels for the rapid transfer of ions. As a result, as-prepared N, P-codoped HCNS/WS2 NSs demonstrated superior rate performance and long-term cycling stability. The reversible discharge capacity of 725.2 mAh·g−1 could be preserved after 1000 cycles at a current density of 1.0 A·g−1. Furthermore, LIHCs devices were assembled by using N, P-codoped HCNS/WS2 NSs and activated carbon (AC) as the cathode and anode, which exhibited high energy density of 166.7 Wh·kg−1 and power density of 5312.4 W·kg−1. Last but not least, the capacity almost had no obvious deterioration after 6000 cycles at a high current density of 10.0 A·g−1.