Cross-linked K2Ti4O9 nanoribbon arrays with superior rate capability and cyclability for lithium-ion batteries

Abstract Cross-linked K2Ti4O9 nanoribbon arrays (KTO-NRAs) have been synthesized and firstly utilized as additive-free anodes for lithium-ion batteries (LIBs). The cross-linked nanoribbon array configuration endows the KTO-NRAs with excellent structural stability and directional ion and electron transport pathways. Meanwhile, the layer structure of K2Ti4O9 nanoribbons offers a large interlayer spacing of 0.91 nm for fast lithium ions insertion/extraction. Consequently, the KTO-NRAs electrode exhibits high reversible capacity (241.5 mAh g−1 at 0.2 A g−1) and superior rate capability (105.9 mAh g−1 at 5.0 A g−1), as well as impressive cyclability (85.5% capacity retention efficiency over 3000 continuous cycles at 2.0 A g−1), holding a good prospect of application in high-performance LIBs.