Titanium dioxide nanostructures for photoelectrochemical applications

This review comprehensively summarized the progresses in the design and modification of titanium dioxide (TiO2) nanostructures as photoelectrode materials for photoelectrochemistry (PEC) applications, mainly in solar-fuel conversion. Various kinds of TiO2 nanostructures including the nanoparticulate, one-dimensional (nanowires, nanorods, nanotubes), two-dimensional (nanobelt, nanoribbon, nanosheet), three-dimensional (meso/nanoporous, branched nanostructures, etc.), and the crystal-facet tailored TiO2 nanostructures are surveyed and discussed. For each type of nanostructure, the commonly-used and effective modification strategies are reviewed followed with a deep discussion on the properties relevant to PEC performances. Moreover, the surface modification approaches (surface disordering, passivation and decoration) on TiO2 nanostructures are highlighted for developing efficient TiO2-based PEC cells. This review will serve as a good resource or guideline for researchers who are currently focusing on TiO2 materials as well as for those who are interested in versatile semiconductor-based PEC applications.