Ultra-high ICE and long cycle stability sodium-ion battery anode: hybrid nanostructure of dominant pyridine N-doped sisal fiber derived carbon-MoS2

Abstract

The development of anode materials with low-cost sustainability and excellent electrochemical properties is imminent for the mass production of sodium-ion batteries (SIBs) for future new energy applications. In this work, sisal fiber was selected as the hard carbon precursor and urea as the dopant to prepare dominant pyridine N-doped tubular sisal fiber carbon (TSFC)-MoS₂ nanosheets for SIB anode materials. The obtained MoS₂/N-TSFC shows ultra-high ICE (93%), high reversible specific capacity (589.4 mAh g⁻¹ at 0.02 A g⁻¹) and an ultra-long cycle life (3000 cycles at 1 A⁻¹). Combined with DFT theoretical calculations, ex situ XRD technique and electrochemical tests, the electrochemical performance enhancement of MoS₂/N-TSFC was investigated, and the results show that the introduction of N can effectively reduce the specific surface area and enhance the adsorption of Na to increase the reversible capacity to obtain ultra-high ICE, the synergistic effect of pyridine N and graphite N can effectively enhance its structural stability to realize the ultra-long cycle life of the material. Therefore, this work balances capacity and ICE perfectly and provides a new strategy for the design of biomass hard carbon anode materials for advanced SIBs.