Shi Yuxiang, Li Ruofan, Zhang Wei-Xian
State Key Laboratory for Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
State Key Laboratory for Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
J Hazard Mater. 2025 Jul 23;496:139308. doi: 10.1016/j.jhazmat.2025.139308.
Sulfur doping into the crystalline lattice of zero-valent iron (ZVI) enhances its electronic properties and local structure, improving its efficacy for transforming environmental contaminants. This study demonstrates a novel high-energy ball milling approach to initiate mechanochemical reactions for precise sulfur doping into the Fe lattice, addressing the hazards posed by hexavalent chromium (Cr(VI)) and trichloroethylene (TCE), two priority pollutants known to threaten public health and ecosystems. Mechanochemically sulfidized ZVI (SZVI, 0.182 %-5.698 % sulfur) exhibited Cr(VI) and TCE removal rates up to 20 and 7 times higher, respectively, than SZVI prepared by conventional solution chemistry with aqueous NaS, forming primarily surface-bound iron sulfides. By tuning milling time to control sulfur incorporation, removal capacities of 130.5 mg/g for Cr(VI) (S: 3.802 %) and 70.1 mg/g for TCE (S: 4.557 %) were achieved under environmentally relevant conditions mimicking groundwater matrices. Mechanical energy catalyzes in-situ iron sulfide (FeS) ieformation through lattice expansion and atomic-scale Fe-S interpenetration, as confirmed by FeS and FeS crystalline phases, symmetric Fe-S bond vibrations, and rearrangement in the Fe coordination environment. These findings advance ZVI-based remediation strategies, mitigating risks from hazardous contaminants in environmental systems.
将硫掺杂到零价铁（ZVI）晶格中可增强其电子性质和局部结构，提高其转化环境污染物的效率。本研究展示了一种新颖的高能球磨方法，该方法可引发机械化学反应，将硫精确掺杂到铁晶格中，以解决六价铬（Cr(VI)）和三氯乙烯（TCE）这两种已知威胁公众健康和生态系统的优先污染物所带来的危害。机械化学硫化的零价铁（SZVI，硫含量为0.182 %-5.698 %）对Cr(VI)和TCE的去除率分别比用传统溶液化学法和硫化钠水溶液制备的SZVI高出20倍和7倍，主要形成表面结合的硫化铁。通过调整球磨时间来控制硫的掺入，在模拟地下水环境的相关条件下，对Cr(VI)（硫含量为3.802 %）的去除能力达到130.5 mg/g，对TCE（硫含量为4.557 %）的去除能力达到70.1 mg/g。机械能通过晶格膨胀和原子尺度的铁-硫互穿催化原位形成硫化铁（FeS），这由FeS和FeS晶相、对称的铁-硫键振动以及铁配位环境的重排所证实。这些发现推进了基于零价铁的修复策略，降低了环境系统中有害污染物的风险。
