u/Mammoth-Ad-3503

I'm currently preparing an oral presentation on photocatalytic concrete and I'm interested in the reaction. After a lot of research, I understand that TiO₂ is primarily used as a catalyst to create two radicals, but I can't find the complete reaction or what happens to the titanium after the formation of OH⁻ and O₂. Any help would be greatly appreciated, and please excuse me if my question isn't worded correctly; I'm not familiar with Reddit, chemistry, or English.