Reducing the photocatalytic activity of zinc oxide quantum dots by surface modification
Version 2 2024-06-05, 03:44Version 2 2024-06-05, 03:44
Version 1 2014-10-28, 08:46Version 1 2014-10-28, 08:46
journal contribution
posted on 2024-06-05, 03:44authored byJ Wang, T Tsuzuki, L Sun, X Wang
The use of zinc oxide (ZnO) nanoparticles as ultraviolet (UV) absorbers for many organic substrates is limited because of the high photocatalytic activity of ZnO. In this study, a facile and efficient technique for the preparation of a hybrid material of silica-coated ZnO nanoparticles was used to reduce the photocatalytic activity of ZnO. Monodispersed ZnO nanopartcles were prepared by wet chemistry and the particle surface was modified by tetraethylorthosilicate to form a silica coating via the Sto¨ ber method. ZnO samples, both before and after the coating process, were investigated by transmission electron microscopy, X-ray diffraction, dynamic light scanning, infrared, and UV-Vis absorption spectroscopy. The effect of the surface modification on the photocatalytic activity of ZnO was studied by monitoring the degradation of Rhodamine B caused by photo-generated free radicals. The results implied that the photo-generation of free-radicals was strongly quenched by the presence of silica on the particle surface.