The controlled study of surfactants on the morphologies of three-dimensional turbine-like V2O5 for the application of high performance lithium ion storage

Abstract

Rationally designing the morphology of V2O5 nanomaterial has caused great significance in the applications of lithium ion storage due to its promising physico-chemical properties. Herein, various V2O5 hierarchical structures have been first successfully synthesized via a facile hydrothermal method followed by an annealing treatment. The V2O5 morphologies undergo a nanoribbon → nanosheet →micro flower structure process with hydrothermal reaction increasing time. After surfactant-assisted hydrothermal process, four types of as-prepared surfactants modified V2O5 exhibit extraordinary valuable morphologies and excellent electrochemical properties in comparison with unmodified V2O5. Especially, cetyltrimethyl ammonium bromide modified V2O5 (defined as V5@CTAB) displays a unique morphology of the combination of three-dimensional (3D) turbine-like micro flowers and low-dimensional nanoparticles. As a thin film cathode material free of binders and conductive agent for lithium-ion batteries, V5@CTAB shows the exceptional high reversible specific capacity of 237 mAh g−1 at current density of 200 uA cm−2, outstanding rate performance, as well as an excellent cycling stability (only 0.10% capacity loss per cycle for 35 cycles). The excellent electrochemical performance might be ascribed that the unique 3D turbine-like microstructure favors the efficient contact between active material and electrolyte, providing more efficient 3D electron transfer pathways, shortening Li+ diffusion distances and thus leading to fast kinetics. These advantages make the 3D turbine-like V2O5 micro flowers structure a promising candidate of the cathode material for lithium-ion batteries.