Near‐Infrared Light Responsive TiO2 for Efficient Solar Energy Utilization

Abstract TiO 2 , as a benchmark in the field of ultraviolet photocatalysis, is one of the most widely used semiconductor photocatalysts. However, its inherent drawbacks, including wide bandgap and fast recombination of charge carriers, lead to the underutilization of solar light. Increasing the overall solar spectrum utilization of TiO 2 , especially in the near‐infrared region (NIR, ≈52%), is the key to efficient solar energy conversion. In this review, the strategies to enhance NIR light capture of TiO 2 ‐based photocatalysts, including hybridization with narrow optical gap semiconductors, bandgap engineering, upconversion materials, plasmonic materials, and photosensitizers, are elaborated. The basic mechanisms for NIR light conversion employed by TiO 2 and the preparation methods of photoactive materials are summarized. Furthermore, their applications in photocatalytic pollutants purification, hydrogen and oxygen evolution, multifunctional smart windows, nitrogen photofixation, as well as carbon dioxide photoreduction and photocatalytic disinfection are discussed. Finally, this review presents the limitations and perspectives for the future development of efficient NIR solar photon conversion of TiO 2 ‐based materials.