Hierarchical Nanorods Constructed by Vertical WS₂ Nanosheets on Carbon Nanotube Cores with Enhanced Lithium Storage Properties

A nanorod hybrid constructed by vertical WS₂ nanosheets on multi-walled carbon nanotubes (MWCNTs) core is synthesized by a facile solvothermal method. The WS₂ nanorod is difficult to form compared to its MoS₂ counterpart because of the relatively sluggish dynamics of W⁴⁺. Herein, multi-site nucleation of WS₂ are initiated by the acid- and heat-treated MWCNT bundles with high concentration of defects and functional groups, forming nanorods with high aspect ratio, and inducing strong interface interaction between MWCNTs and WS₂. WS₂ nanosheets are vertically assembled on the surfaces of MWCNT bundles without agglomeration, exposing abundant active sites for Li⁺ storage. A three-dimensional electron conductive network is formed by the nanorods to improve the charge transport efficiency and alleviate the structure change/restacking of WS₂ during lithium-ion batteries cycling. A specific capacity of 963 mAh g⁻¹ at 0.5 A g⁻¹ after 500 cycles is retained by the nanorod hybrid anode, showing excellent electrochemical performances.