TiO2 beads as photocatalyst and photoelectrode for dye‐sensitized solar cells synthesized by a microwave‐assisted hydrothermal method

In this study, a two‐step process involving a sol–gel and microwave‐assisted hydrothermal (MH) techniques has been used to synthesize a novel TiO₂ structure, namely, TiO₂ mesoporous beads. Various hydrothermal synthesis parameters were investigated to study their effects on the resulting beads. It was found that within the processing conditions used, the TiO₂ beads have similar sizes (~325 nm) and contain uniform‐sized anatase TiO₂ nanoparticles (<10 nm), which are single crystals. Crystalline TiO₂ beads are obtained in as short as 15 min at a low temperature of only 140 °C without any post‐process calcination. Less surface oxygen vacancies was obtained at a higher MH temperature. Compare to the commercial P‐25 TiO₂ powders and conventional hydrothermal synthesized TiO₂ beads, MH synthesized TiO₂ beads exhibit much higher values of specific surface areas, pore volumes, and porosities. The use of TiO₂ beads as photocatalyst and photoelectrode for dye‐sensitized solar cells has also been investigated. Copyright © 2015 John Wiley & Sons, Ltd.