Toward Rapid‐Charging Sodium‐Ion Batteries using Hybrid‐Phase Molybdenum Sulfide Selenide‐Based Anodes
Yongxin Huang, Ziheng Wang, Minrong Guan, Feng Wu, Renjie Chen
Abstract
Abstract To attain both high energy density and power density in sodium‐ion (Na + ) batteries, the reaction kinetics and structural stability of anodes should be improved by materials optimization. In this work, few‐layered molybdenum sulfide selenide (MoSSe) consisting of a mixture of 1T and 2H phases is designed to provide high ionic/electrical conductivities, low Na + diffusion barrier, and stable Na + storage. Reduced graphene oxide (rGO) is used as a conductive matrix to form 3D electron transfer paths. The resulting MoSSe@rGO anode exhibits high capacity and rate performance in both organic and solid‐state electrolytes. The ultrafast Na + storage kinetics of the MoSSe@rGO anode is attributed to the surface‐dominant reaction process and broad Na + channels. In situ and ex situ measurements are conducted to reveal the Na + storage process in MoSSe@rGO. It is found that the MoS and MoSe bonds effectively limit the dissolution of the active materials. The favorable Na + storage kinetics of the MoSSe@rGO electrode are ascribed to its low adsorption energy of −1.997 eV and low diffusion barrier of 0.087 eV. These results reveal that anion doping of metal sulfides is a feasible strategy to develop sodium‐ion batteries with high energy and power densities and long life‐span.