Hetero-assembly of a Li4Ti5O12 nanosheet and multi-walled carbon nanotube nanocomposite for high-performance lithium and sodium ion batteries

Abstract

A nanocomposite composed of crystalline Li₄Ti₅O₁₂ (LTO) nanosheets and multi-walled carbon nanotubes (denoted as LTO/MWCNTs) is prepared for lithium/sodium storage via a facile hetero-assembly process driven by the screening effect of electrostatic repulsion and following thermal treatment. The morphology and microstructure characterizations reveal that LTO nanosheets are embedded in a highly porous and electrically conductive MWCNT network, thereby producing robust inner-connected architectures. Owing to improved electron and ion transportation during electrochemical reaction rendered by a unique integrated architecture of two-dimensional LTO nanosheets and MWCNTs, the nanocomposite exhibits excellent lithium and sodium storage performances. For lithium ion batteries, the anode delivers reversible capacity of 149.7 mA h g⁻¹ at 10C after 500 cycles. As anode for sodium ion batteries, it has reversible capacity of 82 mA h g⁻¹ at 5C. The prepared LTO/MWCNT nanocomposite has great potential as a high-performance anode material for dual storage applications in lithium and sodium ion batteries.