 This review highlights the potential applications of TiO2 in efficient photocatalysis, including various modification strategies such as noble metal deposition, elemental doping, inorganic acid modification, heterojunctions with other semiconductors, disensitization, and metal ion implantation, for enhancing its photocatalytic activities in CO2 conversion, water splitting, and pollutants degradation. This article was authored by M. Humayun, F. Razik, Akon, and others.