Solvothermal synthesis of TiO2 hollow nanospheres utilizing the Kirkendall effect and their photocatalytic activities

- TiO2 hollow nanospheres were formed via the Kirkendall effect.
- Polyethyleneimine quantity influences morphologies of TiO2 dramatically.
- The photodegradation activity of the TiO2 hollow nanosphere is high.
- It was found the active species for the photodegradation reactions is not ·OH.