Department of Environmental Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
China State Construction Engineering Corporation Aecom Consultant Co., Ltd., Lanzhou, 730000, China.
Chemosphere. 2022 Nov;307(Pt 2):135921. doi: 10.1016/j.chemosphere.2022.135921. Epub 2022 Aug 3.
Revealing the activation mechanism of nitrate (NO) reduction is crucially important to design high-efficiency photocatalysts for NO removal. In this work, the performance of photoreduction NO has been thoroughly studied over different crystalline phases TiO. Photodegradation rate of NO over anatase TiO is found to be higher than that of rutile TiO at simulated sunlight, which can achieve high NO conversion of 94% and 100% nitrogen selectivity (original concentration of 50 mg/L NO-N) at reaction time of 4 h. With the aid of in situ Fourier Transform Infrared (FTIR) and density functional theory (DFT) calculations, the possible reaction paths of photoreduction NO over anatase TiO was verified from theory and practice sides. NO was adsorbed on surface Ti site to form bridging nitrate (M - O)NO model. Then, monodentate nitrite (M-O-N-O) model was the dominant intermediate in the reduction process of NO. This study presents a new opinion of photoreduction NO reaction paths.
揭示硝酸盐（NO）还原的活化机制对于设计高效的用于去除 NO 的光催化剂至关重要。在这项工作中，我们在不同晶相 TiO. 上彻底研究了光还原 NO 的性能。在模拟太阳光下，锐钛矿 TiO 的 NO 光降解速率高于金红石 TiO，在 4 h 的反应时间内可实现高的 94%NO 转化率和 100%氮选择性（原始浓度为 50 mg/L 的 NO-N）。借助原位傅里叶变换红外（FTIR）和密度泛函理论（DFT）计算，从理论和实践两个方面验证了锐钛矿 TiO 上光还原 NO 的可能反应途径。NO 吸附在表面 Ti 位上形成桥接硝酸盐（M-O）NO 模型。然后，在 NO 的还原过程中，单齿亚硝酸盐（M-O-N-O）模型是主要的中间体。这项研究提出了光还原 NO 反应途径的新观点。
