Killing two birds with one stone: To eliminate the toxicity and enhance the photocatalytic property of CdS nanobelts by assembling ultrafine TiO2 nanowires on them

Although CdS has been proven to be one of the best photocatalysts in visible light region, its photocorrosion characteristics and toxicity prohibit its practical applications in photocatalytic hydrogen generation and photodegradation of organic pollutants in waste water. In addition, the photocatalytic efficiency of single phase CdS nanostructure is still low due to the recombination of photo-induced carriers. In this paper, a facile modification of CdS nanobelts approach is proposed by assembling TiO2 nanowire on the surface of CdS nanobelts to form TiO2 nanowire/CdS nanobelt hybrid nanstructures. This approach can kill two birds with one stone, that is, to eliminate the photocorrosion induced nontoxicity, and enhance photocatalytic properties by inducing UV light active TiO2 nanowires, and enhance the photo-induced carrier separation ability. The cell cyto-compatibility experiments on TiO2 nanowire/CdS nanobelt hybrid photocatalyst proved that the toxicity of CdS nanobelts can be totally eliminated. At the same time, photodegradation performance of for CdS/TiO2 is over 3 times of that for CdS nanobelts and10 times of that for TiO2. This work gives a new insight in the field of photocatalytic water treatment.