A novel deposition precipitation method for preparation of Ag-loaded titanium dioxide
- PDF / 405,007 Bytes
- 4 Pages / 595 x 794 pts Page_size
- 82 Downloads / 173 Views
Catalysis Letters Vol. 102, Nos. 3–4, August 2005 (Ó 2005) DOI: 10.1007/s10562-005-5863-5
A novel deposition precipitation method for preparation of Ag-loaded titanium dioxide Xianfeng Youa, Feng Chena, Jinlong Zhanga,*, and Masakazu Anpob a
Lab for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P.R. China b Department of Applied Chemistry, Graduate School of Engineering Osaka Prefecture University, 1-1 Gakuen-cho, Sakai Osaka, 599-8531, Japan
Received 18 January 2005; accepted 13 April 2005
Ag/TiO2 photocatalysts were prepared by a novel deposition precipitation method. Formation of Ag nanoparticles on the surface of TiO2 was confirmed by XRD, HRTEM and XPS. The photocatalytic activity of Ag/TiO2 was tested with the photocatalytic degradation of methyl orange and found effectively enhanced. The optimum content of Ag for photocatalytic activity is about 2.0 wt%. KEY WORDS: Ag; TiO2; photocatalytic degradation; methyl orange.
1. Introduction In the past three decades, photocatalysis has attracted much attention owing to its great advantages in the decomposition of organic pollutants in water and air. TiO2, a chemical stable and nontoxic semiconductor, can effectively mineralize most of the organics to CO2, H2O and inorganic ions under UV or solar irradiation. However, the photo-quantum efficiency of TiO2 is greatly limited because of the recombination of photogenerated electrons and holes. Thus, it is of current interest to develop some techniques to depress the electron-hole recombination in TiO2. Besides the semiconductor combination, transition metals doping, TiO2 surface modification with noble metal has been proved as an effective technique to depress the recombination of photogenerated electrons and holes in TiO2. The noble metals deposited on the surface of TiO2, such as Au, Pt and Ag, have excellent exhibitions in promoting the organics degradation with TiO2 under UV irradiation [11–33]. The deposition of Ag on TiO2 was usually carried out with photocatalytic deposition method [44,55], or some involves calcination method [66,77]. Although it hasn’t attracted much attention, another deposition technique, so called deposition precipitation, is also proved to be a competitive method as reported in the preparation of Au/TiO2 for degrading 4-chlorophenol [88]. In this letter, a novel deposition precipitation (DP) method was developed for deposition of metal Ag on TiO2. This novel DP method needs no calcination, which is different from traditional deposition precipitation method. Since neither calcination nor long-term UV irradiation is needed in this DP method, the
* To whom correspondence should be addressed.
agglomeration of Ag particles on the TiO2 could be avoided, comparing with others in the preparation of Ag/TiO2 photocatalyst. The photocatalytic activities of Ag/TiO2 photocatalysts were tested with the photodegradation of methyl orange under UV irradiation.
2. Experimental 2.1. Catalyst preparation The bare TiO2 (ana
Data Loading...
