High performance of anodic TiO2 microcones as negative electrodes for lithium-ion batteries

초록

Recently, nanostructured materials have led to significant improvements of physical properties in lithium ion batteries (LIB). Among them, nanostructured TiO2 is one of potential candidates that can substitute conventional graphite anode owing to nontoxicity, chemically stability and low processing cost. It has been already reported that TiO2 electrode with various morphologies such as nanotubes, nanobelts, nanorods, nanowire and so on has been successfully used as anode for LIBs showing safety and inherent overcharge protection. Herein, highly ordered TiO2 microcones were prepared by anodization of a Ti foil under specific conditions. The as-prepared TiO2 microcones had a hollow core and anatase phase, which were confirmed by SEM, XRD and TEM with EDS mapping. The TiO2 microcone electrodes were evaluated as anodes for lithium-ion batteries, exhibiting excellent electrochemical performance. The areal capacity of TiO2 microcones was higher than that of TiO2 nanotubes and the excellent cycling stability was observed over 500 charge/discharge cycles. The cycled TiO2 microcone electrodes preserved the original morphology of TiO2 microcones due to probably a hollow structure and low volume expansion.