Yang Lin, Yu Yangyang, Yang Wenjia, Li Xiaofang, Zhang Guo, Shen Yu, Dong Fan, Sun Yanjuan
Chongqing Key Laboratory of Catalysis and New Environmental Materials, College of Environment and Resources, National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing, 400067, China.
Yangtze Delta Region Institute (Huzhou) & Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Huzhou, 313001, China.
Environ Res. 2021 Oct;201:111521. doi: 10.1016/j.envres.2021.111521. Epub 2021 Jun 29.
SrSn(OH) (SSOH) possesses a high oxidation potential in the valence band (VB), which is suitable for photocatalytic oxidation removal of pollutants. However, the electrons in the VB of these catalysts are difficult to transition to the conduction band (CB) under visible light, which makes it difficult to utilize sunlight effectively. In this work, Ag/AgO is loaded on the surface of SSOH nanowires, which stimulates the interfacial charge-transfer transition on SSOH. Compared with pure-phase SSOH, the NO abatement ratio of Ag/AgO-SSOH under visible light irradiation is increased to 45.10%. The e in the VB of AgO are excited into the CB under visible light, and are further transferred to the Ag to react with O to produce superoxide radicals. The photo-excited e in the VB of SSOH enter into the VB of AgO through interfacial charge-transfer transition to recombine with the photo-generated holes in the VB of AgO, thereby leaving photo-generated holes in the VB of SSOH. The holes in the VB of SSOH have sufficient oxidizing ability to oxidize the adsorbed hydroxyl groups into hydroxyl radicals. This work provides a new perspective for photocatalytic removal of pollutants by wide band gap photocatalyst under visible light.
SrSn(OH)（SSOH）在价带（VB）中具有较高的氧化电位，适用于光催化氧化去除污染物。然而，这些催化剂价带中的电子在可见光下难以跃迁到导带（CB），这使得难以有效利用太阳光。在这项工作中，Ag/AgO负载在SSOH纳米线表面，这刺激了SSOH上的界面电荷转移跃迁。与纯相SSOH相比，Ag/AgO-SSOH在可见光照射下的NO去除率提高到了45.10%。AgO价带中的电子在可见光下被激发到导带，并进一步转移到Ag与O反应生成超氧自由基。SSOH价带中的光激发电子通过界面电荷转移跃迁进入AgO的价带，与AgO价带中的光生空穴复合，从而在SSOH的价带中留下光生空穴。SSOH价带中的空穴具有足够的氧化能力将吸附的羟基氧化成羟基自由基。这项工作为宽带隙光催化剂在可见光下光催化去除污染物提供了新的视角。
