Photocatalytic growth of CdS, PbS, and CuxS nanoparticles on the nanocrystalline TiO2 films

The CdS/TiO2, PbS/TiO2, and CuxS/TiO2 nanocomposites were synthesized via the photocatalytic reduction of sulfur on the surface of nanocrystalline TiO2 films. The photocatalytic synthesis produced smaller CdS nanoparticles in the comparison with the conventional chemical deposition of cadmium sulfide. The mean size of CdS nanoparticles can be varied by changing the illumination intensity and the TiO2 film calcination temperature.An AFM study of the surface structure of CdS/TiO2 and PbS/TiO2 nanocomposites showed that the photocatalytic deposition results in formation of the polycrystalline 7–80 nm (CdS) or 20–30 nm (PbS) long nanorods. Spatial separation of the photogenerated charge carriers in CdS/TiO2 and PbS/TiO2 nanocomposites was assumed to be the driving force of the formation of such elongated metal sulfide nanoparticle agglomerates.