Recent advances in the synthesis and energy applications of TiO2-graphene nanohybrids

Abstract Owing to its excellent optical, electronic properties, good chemical and thermal stability, titanium dioxide (TiO 2 ) has been applied in promising energy technologies including new dye-sensitized solar cells, rechargeable batteries, supercapacitors, photocatalysts and gas sensors in recent years. However, wide band gap and poor electron transporting ability of TiO 2 has largely limited its application in some aspects like photocatalytic hydrogen generation and lithium ion batteries. Therefore, the modification of TiO 2 is essential for improving its optical and electrical properties. Graphene (GR), a two dimensional carbon nanostructure, is an ideal material to modify TiO 2 owing to its excellent electronic transport properties, exceptional thermal, and electrical conductivity. Compared to a pure TiO 2 nanostructure, the conjugation of GR leads to the increase of its adsorption capacity and photocatalytic activity, and improve the electrical conductivity and Li-ion diffusion pathways. In this review, we have firstly discussed pure TiO 2 nanostructures and introduced different methods for the preparation of TiO 2 -graphene nanohybrids (TiO 2 -GRNHs), and then discussed the practical applications of the TiO 2 -GRNHs in different energy technologies. It is expected that the continuous breakthroughs in the synthesis and modifications of TiO 2 -GRNHs will bring new high-performance materials with exotic properties and potential applications in emerging energy technologies.