Self-supported hierarchical porous Li4Ti5O12/carbon arrays for boosted lithium ion storage

Abstract

Abstract The development of fast rechargeable lithium ion batteries (LIBs) is highly dependent on the innovation of advanced high-power electrode materials. In this work, for the first time, we report a sacrificial NiO arrays template method for controllable synthesis of self-supported hierarchical porous Li4Ti5O12/C (LTO/C) nanoflakes arrays, for use as fast rechargeable anodes for LIBs. The ultrathin (2–3 nm) carbon layer was uniformly coated on the LTO forming arrays architecture. The hierarchical porous LTO/C nanoflakes consisted of primary cross-linked nanoparticles of 50–100 nm and showed large porosity. Because of the enhanced electrical conductivity and accelerated ion transfer channels, the well-designed binder-free porous LTO/C nanoflakes arrays exhibited notable high-rate lithium ion storage performance with smaller polarization, better electrochemical reactivity, higher specific capacity (157 mAh g−1 at the current density of 20C) and improved long-term cycling life (96.2% after 6000 cycles at 20 C), superior to the unmodified porous LTO arrays counterpart (126 mAh g−1 at 20C and 88.0% after 6000 cycles at 20 C). Our work provides a new template for the construction of high-performance high-rate electrodes for electrochemical energy storage.