2D MoS2 grown on biomass-based hollow carbon fibers for energy storage

Abstract 2D MoS 2 sheets have been extensively served as the anode materials for lithium and sodium ion batteries (LIBs, SIBs) due to its high theoretical capacity. However, its low electrical conductivity and large volume change during cycles impair the rate performance and lifespan of the electrodes. Herein, few layer MoS 2 nanosheets vertically grown on biomass-based hollow carbon fibers (BHCFs) derived from palm silk are prepared via a facile hydrothermal method. The density functional theory (DFT) calculations verify an optimized structure of MoS 2 vertically grown on BHCF surface and the strong interaction between the S edges of MoS 2 and the carbon surface. The few layer nanosheets structure and the enhanced conductivity of MoS 2 by biomass derived hollow BHCF ameliorate the diffusion of both Li and Na ions and electrons, as well as the electrode reaction kinetics. Deservedly, the MoS 2 @BHCF electrodes display excellent lithium and sodium storage performance, especially remarkable high-rate capabilities in LIBs. The higher reversible capacity in LIBs than in SIBs reflects the better kinetics of MoS 2 @BHCF in LIBs, owing to a much lower energy barrier of Li atoms diffusing through MoS 2 crystals than the Na counterparts.