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

2D MoS2 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 MoS2 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 MoS2 vertically grown on BHCF surface and the strong interaction between the S edges of MoS2 and the carbon surface. The few layer nanosheets structure and the enhanced conductivity of MoS2 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 MoS2@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 MoS2@BHCF in LIBs, owing to a much lower energy barrier of Li atoms diffusing through MoS2 crystals than the Na counterparts.