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Updated: Aug 14, 2026

Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
Involvement of chloride anion in photocatalytic process
Shi-ying Yang1, Ying-xu Chen, Li-Ping Lou
1Department of Environmental Engineering, Zhejiang University, Hangzhou 310029, China. shiningpup@hotmail.com
Abstract:
The effect of Cl- on photocatalytic degradation (PCD) of pollutants is an important factor since it is ubiquitous in nature. In general, Cl- showed an inhibition on photodegradation due to its scavenging HO* radicals. In this paper, experiments were carried out to examine the effects of Cl- on the PCD of Methylene Blue (MB) and Orange II (OII) in aqueous TiO2 suspensions under UV light illumination. It was found that low concentration of Cl- (< 0.01 mol/L) showed little influence on both dyes, however, high concentration of Cl (> 0.10 mol/L) had a very different influence on the decolorization of dyes: a significant inhibition for MB but a great promotion for OII. In the presence of 0.50 mol/L Cl-, the rate decreased by 70% for MB while increased 7.5-fold for OII. Furthermore, two bands in the ultraviolet region of OII were rapidly broken down. The proposed mechanism was discussed in detail.
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