Interfacial charge regulation in Co-modified WS2/rGO for enhanced sodium storage kinetics

Due to the large ionic radius of Na⁺, sodium storage is often accompanied by sluggish ion transport and limited interfacial reaction kinetics, posing significant challenges for the development of high-performance sodium-ion battery electrode materials. To address these issues, a Co-modified WS 2 /rGO composite was constructed via a hydrothermal method combined with subsequent thermal treatment. The Co-WS 2 /rGO electrode delivers a reversible capacity of 283.5 mAh g -1 after 300 cycles at a current density of 2 A g -1 , along with favorable rate capability. Kinetic analyses reveal a higher surface-controlled contribution and lower charge-transfer resistance for Co-WS 2 /rGO compared with WS 2 /rGO. Operando electrochemical analyses further reveal reduced polarization and improved reaction reversibility during Na⁺ storage. These results demonstrate that Co modification combined with rGO incorporation is an effective strategy for improving the interfacial electrochemical kinetics and sodium-storage performance of WS 2 -based anodes. Download: Download high-res image (196KB) Download: Download full-size image