Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10130933 | Chemical Engineering Journal | 2019 | 30 Pages |
Abstract
ABO3-type perovskite oxides, characterized by high structural flexibility, have found potential applications in many redox processes, including as catalysts for advanced oxidation in wastewater remediation. Here, we demonstrated that by doping the generally believed catalytically inert A-site of LaMnO3 (LMO) perovskite with strontium, the catalytic performance for advanced oxidation is surprisingly boosted. Specifically, La0.4Sr0.6MnO3-δ (LSMO46) was designed which exhibited a high specific activity (0.0608â¯minâ1â¯mâ2) for peroxymonosulfate (PMS) activation, â¼6 times that of LMO and â¼41 times that of reported nanosized MnFe2O4 and Fe/Fe3C. The superior activity was also embodied by low activation energy (44.3â¯kJâ¯molâ1). Moreover, LSMO46 displayed a lower metal leaching and a better reusability than LMO and Fe/Fe3C and easy catalyst recovery for its magnetic behavior. Such enhanced catalytic activity was attributed to the positively-charged surface (8.3â¯mV) that favored the adsorption of negatively-charged organics and the presence of a large amount of surface anion defects (oxygen vacancies), created by the doping, that induced the generation of considerable amount of singlet oxygen (1O2) which was demonstrated as the dominant reactive species by selective radical scavenging and EPR trapping. A coupled activation mechanism involving major singlet oxygen and minor free radicals was further proposed for the effective decomposition of organics in LSMO46/PMS system. The findings in this study thus provide us a new strategy for the development of efficient catalysts for advanced oxidation in environmental treatment.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Jie Miao, Xiaoguang Duan, Jiang Li, Jie Dai, Bo Liu, Shaobin Wang, Wei Zhou, Zongping Shao,