Enhanced Charge Separation in Nanostructured TiO₂ Materials for Photocatalytic and Photovoltaic Applications

Abstract

Titanium dioxide (TiO 2 ) has been extensively investigated in solar energy applications, including heterogeneous photocatalysis and photovoltaics. For most TiO 2 materials, charge recombination between photoexcited electrons and holes severely limits the efficiencies of solar energy conversion. Different strategies have been attempted to improve charge separation in TiO 2 materials. This review focuses on three effective approaches to achieve enhanced charge separation by constructing mixed-phase TiO 2 , highly dispersed titanium oxides, and nanotubular TiO 2 materials. Selected examples from the literature are discussed to demonstrate how the three approaches could be implemented in the context of photocatalytic water splitting, photocatalytic CO 2 reduction, and dye-sensitized solar cells. The discussion provides useful insights regarding the design of new TiO 2 nanostructures for use in solar energy conversion. 2 3 2

Understanding the Reaction Mechanism of Photocatalytic Reduction of CO2 with H2O on TiO2-Based Photocatalysts: A Review

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