Photocatalytic synthesis of TiO ₂ and reduced graphene oxide nanocomposite for lithium ion battery

In this work, we synthesized graphene oxide (GO) using the improved Hummers oxidation method. TiO ₂ nanoparticles can be anchored on the GO sheets via the abundant oxygen-containing functional groups such as epoxy, hydroxyl, carbonyl, and carboxyl groups on the GO sheets. Using the TiO ₂ photocatalyst, the GO was photocatalytically reduced under UV illumination, leading to the production of TiO ₂-reduced graphene oxide (TiO ₂-RGO) nanocomposite. The as-prepared TiO ₂, TiO ₂-GO, and TiO ₂-RGO nanocomposite were used to fabricate lithium ion batteries (LIBs) as the active anode materials and their corresponding lithium ion insertion/extraction performance was evaluated. The resultant LIBs of the TiO ₂-RGO nanocomposite possesses more stable cyclic performance, larger reversible capacity, and better rate capability, compared with that of the pure TiO ₂ and TiO ₂-GO samples. The electrochemical and materials characterization suggest that the graphene network provides efficient pathways for electron transfer, and the TiO ₂ nanoparticles prevent the restacking of the graphene nanosheets, resulting in the improvement in both electric conductivity and specific capacity, respectively. This work suggests that the TiO ₂ based photocatalytic method could be a simple, low-cost, and efficient approach for large-scale production of anode materials for lithium ion batteries.