A chemical etching route to controllable fabrication of TiO₂ hollow nanospheres for enhancing their photocatalytic activity

Abstract

The TiO₂ hollow nanospheres with diameters of about 230 nm were prepared by a simple and controllable route based on hydrolysis of Ti(OBu)₄ on the surfaces of the Cu₂O solid nanospheres followed by inward etching of the Cu₂O nanospheres. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy and scanning electron microscopy. The further post-heat treatment led to the high crystallization of the TiO₂ hollow nanospheres. The photocatalytic performances of these samples were evaluated for the photodegradation of rhodamine B (RhB) under UV-light irradiation. The as-prepared TiO₂ hollow nanospheres showed higher photocatalytic activity than the CuO and the CuO/TiO₂ hollow nanospheres. Effects of temperature and time for post-heat treatment of TiO₂ as well as initial RhB concentrations on the RhB photodegradation have also been studied. The results show that the TiO₂ hollow nanospheres have the good reusability as photocatalysts and are promising in waste water treatment.

Key words： TiO₂; hollow nanospheres; rhodamine B; photocatalytic activity

Acknowledgements

The authors are grateful to the financial supports of the National Natural Science Foundation of China (Grant Nos. 20871038, 20976033, 21176054 and 21271058), the Fundamental Research Funds for the Central Universities (2010HGZY0012) and the Education Department of Anhui Provincial Government (TD200702).

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