title: Preparation of photosensitized nanocrystalline TiO(2) hydrosol by nanosized CdS at low temperature.
abstract: A new method was developed for the fabrication of CdS-TiO(2) semiconductor nanoparticles as visible-light-excitable photocatalyst at low temperatures. Nanosized CdS acting as an effective and stable sensitizer was incorporated into TiO(2) by microemulsion-mediated solvothermal hydrolyzation followed by acidic peptization of the precipitate under 70 °C. The new method avoided the calcination or other pyrochemical treatments involved in traditional preparations, and thus eliminated the unwanted agglomeration of nanoparticles or the oxidation of CdS by oxygen. Compared to traditional methods, it was highly simplified, bypassing those miscellaneous steps like filtration, sintering, milling and redispersion in solutions. The crystal structure, configuration, element composition, as well as the light-absorption properties of the obtained CdS-TiO(2) hydrosol were characterized in detail. The hydrosol consisting of uniform and small crystalline particles of about 2 nm in diameter was thermodynamically stable and showed good dispersibility. The photocatalytic activity of the 'coupled' material was confirmed through the photocatalytic degradation of methylene blue (MB) dye under visible light irradiation, and the cooperative photocatalytic mechanism is discussed.
authors: Department of Chemistry, Wuhan University, Wuhan 430072, People's Republic of China.
authors: Jing-Yu
authors: JY
authors: Wang
authors: Zhi-Hong
authors: ZH
authors: Liu
authors: Qi
authors: Q
authors: Zheng
authors: Zhi-Ke
authors: ZK
authors: He
authors: Ru-Xiu
authors: RX
authors: Cai