School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China.
School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, International Joint Laboratory on Key Techniques in Water Treatment, Henan Normal University, Xinxiang 453007, China.
J Hazard Mater. 2021 Oct 5;419:126499. doi: 10.1016/j.jhazmat.2021.126499. Epub 2021 Jun 25.
Sulfur vacancy (SV) defects have been engineered in two-dimensional (2D) transition metal dichalcogenides (TMDs) for high performance applications in various fields involving environmental protection. Understanding the influence of SVs on the environmental fate and toxicity of TMDs is critical for evaluating their risk. Our work discovered that SVs (with S/Mo ratios of 1.65 and 1.32) reduced the dispersibility and promoted aggregation of 2H phase molybdenum disulfide (2H-MoS, a hot TMD) in aqueous solution. The generation capability of •O and •OH was increased and the dissolution of 2H-MoS was significantly accelerated after SVs formation. Different with pristine form, S-vacant 2H-MoS preferentially harvested proteins (i.e., forming protein corona) involved in antioxidation, photosynthetic electron transport, and the cytoskeleton structure of microalgae. These proteins contain a higher relative number of thiol groups, which exhibited stronger affinity to S-vacant than pristine 2H-MoS, as elucidated by density functional theory calculations. Notably, SVs aggravated algal growth inhibition, oxidative damage, photosynthetic efficiency and cell membrane permeability reduction induced by 2H-MoS due to increased free radical yield and the specific binding of functional proteins. Our findings provide insights into the roles of SVs on the risk of MoS while highlighting the importance of rational design for TMDs application.
硫空位 (SV) 缺陷已在二维 (2D) 过渡金属二硫属化物 (TMD) 中进行了工程设计，以在涉及环境保护的各个领域实现高性能应用。了解 SV 对 TMD 环境归宿和毒性的影响对于评估其风险至关重要。我们的工作发现，SV（S/Mo 比为 1.65 和 1.32）降低了 2H 相二硫化钼（2H-MoS，一种热门 TMD）在水溶液中的分散性，并促进了其聚集。SV 形成后，•O 和 •OH 的生成能力增加，2H-MoS 的溶解速度显著加快。与原始形式不同，S 空位 2H-MoS 优先捕获与抗氧化、光合作用电子传递和微藻细胞骨架结构相关的蛋白质（即形成蛋白质冠）。这些蛋白质含有更高比例的巯基，如密度泛函理论计算所示，其与 S 空位的亲和力强于原始 2H-MoS。值得注意的是，由于自由基产量增加和功能蛋白的特异性结合，SV 加剧了 2H-MoS 引起的藻类生长抑制、氧化损伤、光合作用效率降低和细胞膜通透性降低。我们的研究结果深入了解了 SV 在 MoS 风险中的作用，同时强调了合理设计 TMDs 应用的重要性。
