Zhao Zhiliang, Xiang Leilei, Liu Yu, Qian Jichan, Fu Yuhao, Harindintwali Jean Damascene, Bian Yongrong, Fang Cheng, Jiang Xin, Wang Fang, Naidu Ravi
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 211135, China; University of Chinese Academy of Sciences, Beijing 100049, China; Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Crc for Contamination Assessment and Remediation of the Environment (crcCARE), University of Newcastle, Callaghan, NSW 2308, Australia.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 211135, China; University of Chinese Academy of Sciences, Beijing 100049, China.
J Hazard Mater. 2025 Sep 18;498:139919. doi: 10.1016/j.jhazmat.2025.139919.
Carbon nanotubes (CNT) have been extensively explored for oxidant activation. However, the intrinsic mechanism of CNT-driven ferrate (Fe(VI)) activation remains unclear. This study investigates the catalytic activation of Fe(VI) by CNT and FeO-loaded CNT (FeCNT) using phenanthrene (PHE) as a model to elucidate general oxidation mechanism for organic contaminants. Compared to Fe(VI) alone, Fe(VI)/CNT and Fe(VI)/FeCNT systems significantly increased the degradation rate of PHE by factors of 4.64 and 5.99, respectively. Mechanistic investigations revealed that CNT enhanced the oxidizing ability of high-valent iron and facilitated electron transfer from PHE to high-valent iron, while FeCNT further promoted oxidation through O generation via FeO-mediated HO decomposition. Kinetic modeling quantified the contributions of different reactive species: in the Fe(VI)/CNT system, high-valent iron accounted for 64.05 % of PHE degradation, while CNT catalysis contributed 35.95 %. In the Fe(VI)/FeCNT system, high-valent iron contributed 61.91 %, FeCNT catalysis 31.28 %, and O 6.82 % as extra. Both Fe(VI)/CNT and Fe(VI)/FeCNT systems significantly reduced the toxicity of PHE-contaminated water. Additionally, Fe(VI)/FeCNT retained 93.45 % PHE removal efficiency after five cycles, demonstrating superior reusability and greater resistance. These findings provide new insights into Fe(VI)-based oxidation catalysis and highlight FeCNT as an efficient and durable catalyst for pollutant degradation in complex water matrices.
碳纳米管（CNT）已被广泛用于氧化剂活化研究。然而，碳纳米管驱动高铁酸盐（Fe(VI)）活化的内在机制仍不清楚。本研究以菲（PHE）为模型，研究了碳纳米管和负载FeO的碳纳米管（FeCNT）对Fe(VI)的催化活化作用，以阐明有机污染物的一般氧化机制。与单独的Fe(VI)相比，Fe(VI)/CNT和Fe(VI)/FeCNT体系分别将PHE的降解率显著提高了4.64倍和5.99倍。机理研究表明，碳纳米管增强了高价铁的氧化能力，促进了电子从PHE转移到高价铁，而FeCNT通过FeO介导的HO分解产生O进一步促进氧化。动力学模型量化了不同活性物种的贡献：在Fe(VI)/CNT体系中，高价铁占PHE降解的64.05%，而碳纳米管催化贡献35.95%。在Fe(VI)/FeCNT体系中，高价铁贡献61.91%，FeCNT催化贡献31.28%，额外的O贡献6.82%。Fe(VI)/CNT和Fe(VI)/FeCNT体系均显著降低了PHE污染水的毒性。此外，Fe(VI)/FeCNT在五个循环后仍保留93.45%的PHE去除效率，表现出优异的可重复使用性和更强的抗性。这些发现为基于Fe(VI)的氧化催化提供了新的见解，并突出了FeCNT作为复杂水基质中污染物降解的高效耐用催化剂的作用。
