Executive Summary : | Photocatalysis is the process of light absorption by a semiconductor, followed by the generation of electron-hole pairs used for chemical reactions. Efficient photocatalysis requires quick separation of photogenerated electron-hole pairs to minimize recombination. The primary approach has been the use of an electric field, but recent discoveries have shown that electron spin can also assist in charge separation and reduce recombination through "spin polarization". One approach to achieve spin polarization is to create metal ion vacancies, which result in desired spin orientation. Chemical functionalization can effectively create such vacancies in TiO₂, but the density of such vacancies may not be reproducible. This proposal aims to achieve spin polarization through metal vacancies created by high-energy ion beam irradiation, which can create metal vacancies in TiO₂ in a precise and repeatable manner. The proposal also explores spin-polarized photocatalysts for photocatalytic CO₂ reduction and nano-plastics degradation in water. The proposal is based on the prior experience of the Photoion Photocatalyst (PI) in the fields of photocatalytic CO₂ reduction and high-energy ion beam irradiation. The objective is to explore the effect of employing both charge and spin states of photogenerated electrons to minimize recombination, resulting in greater reaction rate. Environmental concerns and nano-plastic contamination in water bodies are also addressed, and the proposal aims to design and develop novel and tailored photocatalysts to achieve these goals with higher efficiency. |