Reduction and re-oxidation of TiO₂
I can't post a comment, so this is not a true answer but I think can help. If I've understand what you mean you want to perform a Temperature-programmed reduction (TPR) followed by a temperature-programmed oxidation (TPO). In this case I think this old book can help: Temperature-programmed Reduction for Solid Materials Characterization. I don't know much about single crystal but I think that many things from TiO2 studies of nanomaterials can be consider valid for your case, this online book can be helpful to understand all the variables.