Facile synthesis of porous microspheres composed of TiO2 nanorods with high photocatalytic activity for hydrogen production

A facile, high-yield and reproducible hydrothermal route was developed to synthesize novel well-knit (i.e., solid and compacted) and porous anatase TiO2 microspheres, consisting of morphologically controlled and uniform TiO2 nanorods. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) revealed that the resulting TiO2 microspheres exhibited a nanoporous structure that was formed by the self-assembled accumulation of uniform nanorods, which is reported here for the first time. The effect of the surfactant type, surfactant amount and other additives such as urea and water on the formation of the microspheres was investigated. X-ray diffraction and N-2 adsorption-desorption characterization showed that the synthesized TiO2 microspheres exhibited a high degree of crystallinity with a high surface area (similar to 103.9 m(2)/g), which was twice larger than that of commercial P25. The synthesized TiO2 microsphere photocatalysts also exhibited superior photocurrent density with a 4.8-fold improvement in photocurrent over the commercial P25. Additionally, these TiO2 microspheres showed good performance in the generation of hydrogen. (C) 2013 Elsevier B.V. All rights reserved.