Intrinsic structure-function connections of carbon-encapsulated nanoscale zero-valent-iron using various pyrolysis atmospheres

• Published in: Journal of environmental management Vol. 373; p. 123768
• Main Authors: Yang, Lu, Jin, Xiaoying, Chen, Zuliang
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2025
• Subjects: 2,4,6-trichlorophenol; air; carbon; Carbon - chemistry; Carbon-encapsulated nanoscale zero-valent-iron; Chlorophenols - chemistry; dechlorination; density functional theory; electrochemistry; Electronic structure; environmental management; guidelines; hybridization; Hydrophobicity; Iron - chemistry; nitrogen; Pyrolysis; Pyrolysis atmosphere engineering; Structure-function connections; toxicity; Electronic structure; Hydrophobicity; Carbon-encapsulated nanoscale zero-valent-iron; Structure-function connections; Pyrolysis atmosphere engineering
• ISSN: 0301-4797; 1095-8630; 1095-8630
• DOI: 10.1016/j.jenvman.2024.123768

Carbon-encapsulated nanoscale zero-valent-iron (C@Fe0) derived from plant-based extracts has been the subject of growing interest due to its environmental friendliness. However, the effects of various pyrolysis atmospheres on the structure-function connections of C@Fe0 are still unclear. In this study, three pyrolytic atmospheres, namely Air, N2, and 5% H2/Ar were selected to fabricate X-C@Fe0 (X represented as A, N, H) for removing 2,4,6-Trichlorophenol (TCP), and the relationships between their structures and functions were demonstrated. The N-C@Fe0 with improved hydrophobicity exhibited superior TCP adsorptive performance compared to H-C@Fe0 and A-C@Fe0. Apart from this, N-C@Fe0 effectively reduced TCP through dechlorination, this process achieved 25.9% dichlorination efficiency, and in turn alleviated products toxicity. Electrochemical tests and density functional theory calculations showed that the substitution of nitrogen with carbon in N-C@Fe0 elevated the Fe-d band center and enhanced the hybridization between Fe-3d and C-2p orbital, which collectively promoted the dichlorination of TCP. This study will provide practical guideline for improving the intrinsic activity of iron-carbon materials using pyrolytic atmosphere engineering. [Display omitted] •Different C@Fe0 was successfully prepared under Air, N2, and H2/Ar, respectively.•The intrinsic structure-function connections of C@Fe0 were investigated.•N2 atmosphere made C@Fe0 more hydrophobic than Air and H2/Ar.•Pyrolytic atmosphere-impacted electronic structure was elucidated.