Ordered mesoporous carbon-TiO2 materials for improved electrochemical performance of lithium ion battery

A series of ordered mesoporous carbon-TiO2 (OMCT) materials with various weight percentages of TiO2 (50-75 wt%) were synthesized by evaporation-induced self-assembly and in-situ crystallization at various calcination temperatures (600-1200 degrees C) to evaluate the Li-ion storage performance. The OMCT has ordered 2D hexagonal mesoporous structures and the TiO2 nanocrystals with different phases are embedded into the frameworks of carbonaceous matrix. The reversible capacity of OMCT is highly dependent on the phase and content of TiO2, and the anatase TiO2 is a superior crystalline phase to rutile and TiN for Liion insertion. The OMCT65 which contains 35 wt% carbon and 65 wt% TiO2 shows a high capacity of 500 mAh g(-1) at 0.1C after 80 cycles. In addition, OMCT65 exhibits a good cyclability and rate capability. The reversible capacity remains at 98 mAh g(-1) at a high rate of 5C, and then recoveries to 520 mAh g(-1) at 0.1C after 105 cycles. The excellent reversible capacity and rate capability of OMCT65 are attributed to the embedment of well-dispersed anatase TiO2 nanocrystals into the specific porous structure of OMCT, which can not only facilitate the fast Li-ion charge transport but can also strengthen the carbon-TiO2 coconstructing channels for lithiated reactions. (C) 2012 Elsevier Ltd. All rights reserved.