A facile method to prepare monodispersed CdS/SiO2 composite microspheres and investigation on their photocatalytic properties.

This article presents a facile method to prepare CdS/SiO(2) composite microspheres and their good catalytic properties. In our method, monodispersed SiO(2) particles bearing amino groups (-NH(2)) were synthesized at first and then used as carriers to load nanosized CdS particles to form CdS/SiO(2) composite microspheres. With the addition of CdAc(2) solution to the SiO(2) dispersion, Cd(2+) was attracted to the surfaces of the SiO(2) particles through coordination interaction, and then thioacetamide was added to the dispersion. By heating, S(2-) released and reacted with the Cd(2+), CdS/SiO(2) composite microspheres were obtained accordingly. The photocatalytic properties of the as-prepared composite microspheres were investigated as well. It was found that the composite microspheres have excellent photocatalytic activities for the degradation of dyes comparing with the commercial P-25 TiO(2) catalysts. After using and recycling for three times, the photocatalytic performance still remained very well.