Mechanistic Understanding in Manipulating Energetics of TiO<sub>2</sub> for Photocatalysis
Rayhan Hossain, Md Aslam Uddin, M. Arif Khan
Abstract
Titanium dioxide (TiO 2 ) is a wide bandgap semiconductor that has a wide range of applications including wastewater treatment, photocatalysis, solar cells, and sensors owing to its excellent electronic and optical properties. However, the wide bandgap of TiO 2 (∼3.2 eV) along with the recombination processes of the photoexcited charge carriers reduce its interfacial charge transport properties and respective activities. Energetics, optical response, and corresponding photophysics of excited charge carriers can be altered through doping and codoping of TiO 2 and composite formulation . Therefore, it is very crucial to understand the structure–property and property-application relationships of doped, co-doped, and composite TiO 2 to maximize the efficiency and extend the fundamental understanding for their applications in different fields. In this Perspective, we summarize the ongoing research on the advancement of undoped, doped, co-doped, and composite TiO 2 including their structure and morphology, energetics, and corresponding photophysics relative to their applications in photocatalysis, wastewater treatment, and water-splitting reactions. We then propose our perspectives on the future potential of energetic manipulation of photocatalytic TiO 2 to develop advanced and highly efficacious catalytic materials.