Open AccessMechanism of Photodegradation of Organic Pollutants in Seawater by TiO2-Based Photocatalysts and Improvement in Their Performance
Author(s) -
Hengtao Xu,
Zhe Hao,
Wei Feng,
Ting Wang,
Yao Li
Publication year - 2021
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.1c04604
Subject(s) - catalysis , photodegradation , seawater , adsorption , photocatalysis , pollutant , salt (chemistry) , degradation (telecommunications) , ethylene glycol , inorganic chemistry , chemical engineering , chemistry , materials science , photochemistry , organic chemistry , telecommunications , oceanography , computer science , engineering , geology
The mechanism of photodegradation of organic pollutants in seawater by TiO 2 -based catalysts irradiated by visible light was first explored by adding holes and free radical traps. The results showed that the photogenerated holes formed by the catalyst played a key role in the degradation of organic pollutants, regardless of whether the photodegradation occurred in seawater or pure water. Considering that the Yb-TiO 2 -rGO catalyst has a strong adsorption for organics, the salt ion almost did not interfere with the adsorption of pollutants by Yb-TiO 2 -rGO. Therefore, the degradation performance of Yb-TiO 2 -rGO did not remarkably change in the two water systems. For P25-ZN with a weak adsorption capacity for organics, several salt ions in the seawater hindered the contact of pollutants with the catalyst surface. Thus, the degradation rate of P25-ZN for phenol was significantly reduced. After the solvothermal reduction treatment for catalysts using ethylene glycol (EG) as the solvent, the increase in the Ti 3+ content in the catalyst improved the visible-light response and activity of the catalyst. In addition, a small amount of EG grafted on the catalyst surface promoted the photocatalytic reaction process on the catalyst surface, thereby effectively resisting the interference of salt ions.