TiO2@CdSe/CdS core–shell hollow nanospheres solar paint

Abstract

TiO₂@CdSe/CdS core–shell hollow nanospheres solar paint was successfully prepared via hard template and ion exchange method considering the match of their band gap. The outer layer of TiO₂ shell protects CdSe and CdS from decomposition and increases their stability. The diameters of the TiO₂@CdSe/CdS hollow nanospheres were uniformly around 600 nm with a shell thickness of 70 nm. The visible light absorption onset of TiO₂@CdSe/CdS hollow nanospheres is around 650 nm corresponding to a bandgap of 1.8 eV, showing a red-shift when compared with TiO₂/CdS. TiO₂@CdSe/CdS hollow nanospheres can be directly used as solar paint. The photoanode decorated by the solar paint performs a reliable photoelectric conversion efficiency of ∼0.79% and current density of 6.6 mA cm⁻².