Shi Yinghao, Lyu Honghong, Guo Saisai, Guo Jiaming, Gao Feilong, Tang Jingchun
MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.
J Hazard Mater. 2025 Aug 15;494:138402. doi: 10.1016/j.jhazmat.2025.138402. Epub 2025 May 3.
Conventional zero-valent iron (ZVI) materials are limited by the constraints of reactivity-selectivity-stability trade-offs, so designing multi-heteroatom co-modified ZVI with synergistic effects is gradually gaining popularity. Herein, we developed a novel co-modified nZVI by simultaneously doping sulfur (S) and phosphorus (P) heteroatoms into nZVI using the one-step liquid-phase reduction method. In this case, the faster diffusion rate of core iron atoms compared to shell components triggeres multiple Kirkendall effects, causing the inward diffusion of vacancies with further coalescing into radial nanocracks. Regarding the reactivity and selectivity, sulfidation and phosphorylation co-modified nZVI exhibited the best performance, with a trichloroethylene (TCE) dechlorination rate (k) of 0.65 h and an electron efficiency (ε) of 14.5 %, which are 20.9 and 13.8 times higher than those of unmodified nZVI. A series of characterizations and electrochemical analyses indicated that S and P doping significantly altered the physicochemical properties of the core and shell layers, generating distinctive "lemon slice" nanocracks that could be used as electron transport channels, and FeS significantly reduced the availability of hydrogen evolution reaction (HER) active surface sites and attenuates the passivation of nZVI. In addition, the co-modified S/P-nZVI exhibited excellent stability in different groundwater conditions, indicating its strong potential for application.
传统的零价铁（ZVI）材料受到反应性-选择性-稳定性权衡的限制，因此设计具有协同效应的多杂原子共修饰ZVI正逐渐受到关注。在此，我们采用一步液相还原法，通过同时将硫（S）和磷（P）杂原子掺杂到纳米零价铁（nZVI）中，开发了一种新型的共修饰nZVI。在这种情况下，核心铁原子的扩散速率比壳层组分更快，引发了多个柯肯达尔效应，导致空位向内扩散并进一步聚合成径向纳米裂纹。在反应性和选择性方面，硫化和磷化共修饰的nZVI表现出最佳性能，三氯乙烯（TCE）脱氯速率（k）为0.65 h，电子效率（ε）为14.5%，分别是未修饰nZVI的20.9倍和13.8倍。一系列表征和电化学分析表明，S和P掺杂显著改变了核心和壳层的物理化学性质，产生了独特的“柠檬片”纳米裂纹，可作为电子传输通道，并且FeS显著降低了析氢反应（HER）活性表面位点的可用性并减弱了nZVI的钝化。此外，共修饰的S/P-nZVI在不同的地下水条件下表现出优异的稳定性，表明其具有很强的应用潜力。
