Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China.
Shenzhen Geim Graphene Center, Engineering Laboratory for Functionalized Carbon Materials, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China.
J Hazard Mater. 2021 Jul 5;413:125424. doi: 10.1016/j.jhazmat.2021.125424. Epub 2021 Feb 13.
Photocatalysis is an effective method to degrade ranitidine (RAN), which is a typical precursor of nitrosamine dimethylamine (NDMA), an extremely potent human carcinogen. Herein, MXene-TiC/MoS composites were prepared by a hydrothermal treatment aiming to use them for the photocatalytic degradation of RAN and the reduction of NDMA formation potential (NDMA-FP) under visible light irradiation for the first time. The analysis of the morphology, chemical composition and structure of these composites as well as the results of electrochemical experiments showed that a heterojunction was formed between MoS and TiC, which facilitated the separation of electron-hole pairs and charge transfer, and thereby the photocatalytic performance. The MXene-TiC/MoS composite (MT-4) exhibited the best photocatalytic performance in 60 min, with the highest RAN degradation and mineralization efficiencies of 88.4% and 73.58%, and the lowest NDMA-FP of 2.01%. Active species, including •O radicals, h and •OH radicals, all contributed to the degradation of RAN, among which •OH radicals were the main active species involved in the photocatalytic activity. The mechanism of the photocatalytic degradation of RAN over MXene-TiC/MoS photocatalyst under visible light irradiation was proposed. This work opens up a new perspective on the applications of MXene-based materials for photocatalytic degradation of challenging pollutants.
光催化是一种有效降解雷尼替丁（RAN）的方法，RAN 是亚硝胺二甲胺（NDMA）的典型前体，NDMA 是一种极其强效的人类致癌物质。在此，首次通过水热处理制备了 MXene-TiC/MoS 复合材料，旨在将其用于可见光照射下 RAN 的光催化降解和 NDMA 形成潜能（NDMA-FP）的降低。这些复合材料的形貌、化学成分和结构分析以及电化学实验结果表明，MoS 和 TiC 之间形成了异质结，这促进了电子空穴对的分离和电荷转移，从而提高了光催化性能。在 60 分钟内，MXene-TiC/MoS 复合材料（MT-4）表现出最佳的光催化性能，RAN 的降解和矿化效率最高，分别为 88.4%和 73.58%，NDMA-FP 最低，为 2.01%。包括•O 自由基、h 和•OH 自由基在内的活性物质都有助于 RAN 的降解，其中•OH 自由基是参与光催化活性的主要活性物质。提出了在可见光照射下 MXene-TiC/MoS 光催化剂上光催化降解 RAN 的机制。这项工作为 MXene 基材料在光催化降解挑战性污染物方面的应用开辟了新的视角。
