Effect of Sn surface states on the photocatalytic activity of anatase TiO2

- Isolated Sn(IV) was successfully grafted on anatase TiO2 by a simple procedure.
- Preferential reduction of surface Sn over Ti leads to the formation of Sn(II) surface species.
- Sn(II) surface species act as surface trapper sites for holes produced under irradiation.
- Sn(II) surface states enhance the photocatalytic efficiency for methylene blue degradation.