Binder-free α-MoO3 nanobelt electrode for lithium-ion batteries utilizing van der Waals forces for film formation and connection with current collector

Abstract

We demonstrate a facile and effective way for the fabrication of a flexible, homogeneous and neat α-MoO₃ thin-film electrode for lithium-ion batteries with high performance without using any binder and conductive additives. Single-crystalline α-MoO₃ nanobelts with uniform width of around 200 nm and length at the micrometer level are first synthesized by a simple water-based hydrothermal route. The as-obtained α-MoO₃ slurry is then directly deposited onto a copper foil current collector by the doctor blade method. The formation of the α-MoO₃ film and its good adhesion to the current collector is realized via van der Waals attraction forces through a drying process. The structure and morphology of the α-MoO₃ nanobelt particles and thin-film electrode are systematically characterized by XRD, Raman spectra, TEM, SEM and XPS techniques, and the electrochemical properties are investigated by CV and constant current discharge–charge test techniques. The α-MoO₃ film electrode exhibits a reversible specific capacity of ∼1000 mA h g⁻¹ at 50 mA g⁻¹ and a stable capacity retention of 387–443 mA h g⁻¹ at 2000 mA g⁻¹, indicating its high Li storage capacity, superior rate performance and good cycling stability. The electrode material, as well as the fabrication technique, is highly promising for practical use in high energy and power density lithium-ion batteries.