Ultrafine TiO2 nanoparticles on reduced graphene oxide as anode materials for lithium ion batteries

Abstract

TiO2 nanoparticles/reduced graphene oxide (TiO2/rGO) was prepared by controllable hydrolysis and followed by thermal treatment. First, hydrolysis of titanium isopropoxide formed amorphous titanium hydroxide thin layer on graphene oxide (GO). After annealing at 450°C under forming gas, amorphous titanium hydroxide layer converted to TiO2 nanoparticles with particle size of around 5nm and GO reduced to rGO with enhanced conductivity. TiO2/rGO was demonstrated as promising anode materials for high performance lithium ion batteries. The high operation potential window of TiO2 in lithium ion battery can prevent the formation of solid electrolyte interface and subsequently enhance the safety and cycle performance. The high rate and high cycling performance of lithium ion batteries could be ascribed to that the ultrafine TiO2 nanoparticles provide high active surface area and the strong connection between TiO2 and high conductive rGO network can enhance the charge transfer.