Soft-template-assisted synthesis of Petals-like MoS2 nanosheets covered with N-doped carbon for long cycle-life sodium-ion battery anode

Abstract

The Petals-like N -doped carbon@MoS 2 (N–C@MoS 2 ) nanosheets are elaborately constructed by g-C 3 N 4 soft-template. As a remarkable anode for SIBs, the N–C@MoS 2 electrode has long-term stability properties, which delivers high capacities of 246 mA h/g at 1.5 A/g after 1000 cycles. • G-C 3 N 4 template inhibits the agglomeration of MoS 2 and realize nitrogen doping of carbon layer. • N -doped carbon layers can improve electronic conductivity and ionic diffusion rate. • The electrode can deliver the capacity of 246 mA h g −1 at 1.5 A/g after 1000 cycles. • The superior performance is ascribed to enhanced conductivity and alleviation volume variation. Molybdenum disulphide (MoS 2 ) is a promising anode material for sodium-ion batteries (SIBs) owing to its graphene-like layered structure and high-capacity (670 mAh/g). However, its inherent poor electrical conductivity and slow Na-ion transportation are the two vital factors limiting its application in SIBs. Herein, the petals-like N -doped carbon@MoS 2 (N–C@MoS 2 ) nanosheets anode are elaborately constructed by the MoS 2 host, g-C 3 N 4 soft-template and carbonated pyrrole conductive matrix. Particularly, the g-C 3 N 4 as a soft-template can effectively inhibit the agglomeration of MoS 2 nanosheets during high temperature treatment and realize nitrogen doped of carbon layer. Most importantly, N -doped carbon layers can improve the electronic ionic diffusion rate and conductivity as well as generate numerous active sites. The volume expansion of MoS 2 is also mitigated due to the constraint of carbon layer by improving the surface electrical property and surface activity. Therefore, the N–C@MoS 2 electrode displays excellent long cycle-life and high-capacity as SIBs anode, which delivers high-capacity of 399 and 246 mAh/g after 300 and 1000 cycles at 0.2 and 1.5 A/g, respectively. The idea of preparing N–C@MoS 2 composite material based on g-C 3 N 4 soft-template afford experimental origin for the further progress of Na-storage device and can be certainly stretched to other transition metal compounds that can form composite structure with g-C 3 N 4 .