Photo degradation of methyl orange by attapulgite-SnO2-TiO2 nanocomposites.
Photocatalytic removal of methyl orange under ultraviolet radiation has been studied using attapulgite (ATT) composites, which were synthesized by depositing SnO(2)-TiO(2) hybrid oxides on the surface of ATT to form a composite photocatalyst (denoted ATT-SnO(2)-TiO(2)) using an in situ sol-gel technique. Results showed that SnO(2)-TiO(2) nanocomposite particles with average size of about 10nm were loaded successfully on to the surface of ATT fibers and were widely dispersed. Correspondingly, the photocatalytic activity of ATT was improved significantly by loading SnO(2)-TiO(2). The photoactivity of the composite photocatalyst decreased in the sequence ATT-SnO(2)-TiO(2)>ATT-SnO(2)>ATT-TiO(2)>ATT. In order to achieve the best photocatalyst, the molar ratio of SnO(2) and TiO(2) in the ATT-SnO(2)-TiO(2) composites was adjusted to give a series with proportions r=n(Ti)/(n(Ti)+n(Sn))=0.0, 0.25, 0.33, 0.50, 0.67, 0.75, 0.80, 0.82, 0.86, 1.0. Results indicated that the proportion of SnO(2) and TiO(2) had a critical effect on the photocatalytic activity, which increased as the content of TiO(2) increased to r<or=0.82 and decreased when r>0.82. The highest degradation rate of methyl orange was 99% within 30 min obtained by using ATT-SnO(2)-TiO(2) with r=0.82. The repeated use of the composite photocatalyst was also confirmed.
Zhang
Lili
L
Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials, Huaiyin Normal University, Huai'an 223300, China. Zhanglily800@yahoo.com.cn
Lv
Fujian
F
Zhang
Weiguang
W
Li
Rongqing
R
Zhong
Hui
H
Zhao
Yijiang
Y
Zhang
Yu
Y
Wang
Xin
X
D000327:Adsorption; D001391:Azo Compounds / Q000737:chemistry*; D002384:Catalysis; D017616:Magnesium Compounds / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D009584:Nitrogen / Q000737:chemistry; D044367:Phase Transition; D055668:Photochemical Processes; D010777:Photochemistry / Q000379:methods*; D017655:Silicon Compounds / Q000737:chemistry*; D013696:Temperature; D017971:Tin Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
D001391:Azo Compounds; D017616:Magnesium Compounds; D017655:Silicon Compounds; D017971:Tin Compounds; C009495:titanium dioxide; C100258:methyl orange; D014025:Titanium; C045358:stannic oxide; D009584:Nitrogen; C026325:attapulgite