Construction of hierarchical C/MoS nanobelts wrapped by N-doped carbon toward high-performance lithium/sodium storage.

As an ideal choice for anode materials in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), molybdenum disulfide (MoS) still encounters the obstacles of undesirable conductivity, volume expansion and self-agglomeration during cycling that need to be conquered. Herein, a novel hierarchical nanobelt structure of N-doped carbon-coated C/MoS (denoted as C/MoS@NC) was synthesized by self-sacrificing template method and facile double carbon coating process. In this hierarchical structure, MoS nanosheets grown vertically along the nanobelt axis offer a plethora of active sites for electrode reaction and expedite the transport of Li/Na, thus promoting the electrochemical process. Furthermore, the double carbon coating effectively enhances the conductivity of MoS and alleviates its volume expansion, wherein the inner carbon playing a pivotal role in preserving the nanobelt structure, while the outermost N-doped carbon effectively prevents polysulfide dissolution and further reinforce structural stability. Consequently, the C/MoS@NC-2 electrode presents exceptional electrochemical behavior for both LIBs (1254 mAh g at 0.2 A g after 100 cycles, 884 mAh g at 1 A g after 500 cycles, and rate capacity of 629 mAh g at 10 A g) and SIBs (441 mAh g at 0.2 A g after 100 cycles and capacity retention rate of 80.4 % after 1000 cycles at 1 A g). Moreover, the Li/Na-ion full cells show good cycling stability, confirming the C/MoS@NC-2 electrode's viability for practical applications in these energy storage systems.