Liu Meiling, Quan Yan, Feng Mengjie, Ren Chunguang, Wang Zhonghua
Chemical Synthesis and Pollution Control Key Laboratory, College of Chemistry and Chemical Engineering, China West Normal University Nanchong 637002 Sichuan China
School of Pharmacy, Yantai University Yantai 264005 Shandong China
RSC Adv. 2024 Sep 30;14(42):31193-31204. doi: 10.1039/d4ra05539j. eCollection 2024 Sep 24.
Semiconductor photocatalytic technology is increasingly being utilized in wastewater treatment due to its high efficiency, low energy consumption and environmental friendliness. However, single photocatalysts often exhibit low catalytic performance. In this study, a ZnFeO/AgI composite photocatalyst was initially prepared using a high-energy ball-milling method. For the first time, it was applied to the photocatalytic dehydrogenation of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (1,4-DHP), as well as photocatalytic degradation of harmful substances such as amaranth (AM), methyl orange (MO) and indole present in wastewater. The composite photocatalyst exhibited superior catalytic performance compared to ZnFeO and AgI under visible light irradiation ( ≥ 400 nm). With optimized composition, the pseudo-first-order rate constants of ZnFeO/AgI-50% were approximately 6, 20, 64 and 38 times higher than that of AgI for the photooxidation of 1,4-DHP, AM, MO and indole, respectively. The enhanced catalytic activity of the composite was attributed to the formation of heterojunction between ZnFeO and AgI, which facilitated the separation and transfer of photogenerated charge carriers. Mechanism studies revealed that photogenerated holes (h) and superoxide radical anions (˙O ) played pivotal roles in the photocatalytic reaction process.
半导体光催化技术因其高效、低能耗和环境友好性，在废水处理中得到越来越广泛的应用。然而，单一光催化剂的催化性能往往较低。在本研究中，首次采用高能球磨法制备了ZnFeO/AgI复合光催化剂。该复合光催化剂首次应用于1,4 - 二氢 - 2,6 - 二甲基吡啶 - 3,5 - 二羧酸二乙酯（1,4 - DHP）的光催化脱氢反应，以及废水中苋菜红（AM）、甲基橙（MO）和吲哚等有害物质的光催化降解反应。在可见光（≥400 nm）照射下，该复合光催化剂表现出比ZnFeO和AgI更优异的催化性能。通过优化组成，ZnFeO/AgI - 50%对1,4 - DHP、AM、MO和吲哚光氧化反应的准一级反应速率常数分别约为AgI的6倍、20倍、64倍和38倍。复合光催化剂催化活性的增强归因于ZnFeO和AgI之间形成了异质结，促进了光生载流子的分离和转移。机理研究表明，光生空穴（h）和超氧自由基阴离子（˙O ）在光催化反应过程中起关键作用。
