A review of one-dimensional TiO2 nanostructured materials for environmental and energy applications

One-dimensional TiO2 (1D TiO2) nanomaterials with unique structural and functional properties have been extensively used in various fields including photocatalytic degradation of pollutants, photocatalytic CO2 reduction into energy fuels, water splitting, solar cells, supercapacitors and lithium-ion batteries. In the past few decades, 1D TiO2 nanostructured materials with a well-controlled size and morphology have been designed and synthesized. Compared to 0D and 2D nanostructures, more attention has been paid to 1D TiO2 nanostructures due to their high aspect ratio, large specific surface area, and excellent electronic or ionic charge transport properties. In this review, we present the crystal structure of TiO2 and the latest development on the fabrication of 1D TiO2 nanostructured materials. Besides, we will look into some critical engineering strategies that give rise to the excellent properties of 1D TiO2 nanostructures such as improved enlargement of the surface area, light absorption and efficient separation of electrons/holes that benefit their potential applications. Moreover, their corresponding environmental and energy applications are described and discussed. With the fast development of the current economy and technology, more and more effort will be put into endowing TiO2-based materials with advanced functionalities and other promising applications.