Amorphous carbon intercalated <scp>MoS<sub>2</sub></scp> nanosheets embedded on reduced graphene oxide for excellent high‐rate and ultralong cycling sodium storage
Jun Xu, Junbao Jiang, Shoufu Cao, Suwan Li, Yuanming Ma, Junwei Chen, Y. Zhang, Xiaoqing Lü
Abstract
Abstract MoS 2 as a typical layered transition metal dichalcogenide (LTMD) has attracted considerable attention to work as sodium host materials for sodium‐ion batteries (SIBs). However, it suffers from low semiconducting behavior and high Na + diffusion barriers. Herein, intercalation of N‐doped amorphous carbon (NAC) into each interlayer of the tiny MoS 2 nanosheets embedded on rGO conductive network is achieved, resulting in formation of rGO@MoS 2 /NAC hierarchy with interoverlapped MoS 2 /NAC superlattices for high‐performance SIBs. Attributed to intercalation of NAC, the resulting MoS 2 /NAC superlattices with wide MoS 2 interlayer of 1.02 nm facilitates rapid Na + insertion/extraction and accelerates reaction kinetics. Theoretical calculations uncover that the MoS 2 /NAC superlattices are beneficial for enhanced electron transport, decreased Na + diffusion barrier and improved Na + adsorption energy. The rGO@MoS 2 /NAC anode presents significantly improved high‐rate capabilities of 228, 207, and 166 mAh g −1 at 20, 30, and 50 A g −1 , respectively, compared with two control samples of pristine MoS 2 and MoS 2 /NAC counterparts. Excellent long‐term cyclability over 10 000 cycles with extremely low capacity decay is demonstrated at high current densities of 20 and 50 A g −1 . Sodium‐ion full cells based on the rGO@MoS 2 /NAC anode are also demonstrated, yielding decent cycling stability of 200 cycles at 5C. Our work provides a novel interlayer strategy to regulate electron/Na + transport for fast‐charging SIBs. image