Key points are not available for this paper at this time.
Highly photoactive, tetrahedral Ti4+ sites can be created, other than in zeolite cavities and on silica substrate, in mixed-phase TiO2 nanocomposites. The tetrahedral Ti4+ species was shown to be an intermediate formed during the thermally driven phase transformation from anatase to rutile.
Li et al. (Fri,) studied this question.