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Research Article

Natural keratin-based Fe-S1N3 single atom catalyst for insights into the coordination regulation effect of Fenton-like catalysis with high efficiency

Zhiyi Sun1,2, Yujuan Wei2, Ting Cao3,4, Zheng Liu3,4( ), Rui Sui5, Xiang Li6( ), Jiajing Pei7, Zhuo Chen1, Shuo Wang2( )
Energy & Catalysis Center, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
College of Textile and Garments, Hebei University of Science & Technology, The Innovation Center of Textile and Garment Technology, Hebei 050018, China
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
SEPA Key Laboratory of Eco-Industry, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
Department of Chemistry, Tsinghua University, Beijing 100084, China
Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
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Graphical Abstract

A series of Fenton-like single atom catalysts (SACs) for the oxidative degradation of organic pollutants were synthesized by extracting keratin from wool natural fibers to anchor isolated metal sites. Compared with silk fibroin-based samples, the rich disulfide bonds in wool protein act as sulfur sources, introducing highly electronegative N atoms into the catalyst to optimize the local coordination environment of Fe atoms, which is expected to enhance the Fenton-like catalytic performance.

Abstract

Single atom catalysts (SACs) have attracted great attention, yet the quest for highly-efficient catalysts is driven by the current obstacles of ambiguous structure-performance relationship. Here, we report a nature keratin-based Fe-S1N3 SACs with ultrathin two-dimensional (2D) porous carbon nanosheets structure, by controlling the active center through the precise coordination of sulfur and nitrogen. Compared with natural silk-based Fe-N4 catalyst, the Fe-S1N3 SACs exhibit excellent Fenton-like oxidation degradation ability. X-ray absorption fine structure (XAFS) and electron paramagnetic resonance (EPR) results confirm that S doping is conducive to electron transfer, to accurately generate ·OH with high oxidative degradation capacity at the active site. Therefore, the optimized Fe-S1N3 catalyst showed higher oxidation degradation activity for organic pollutant substrates (methylene blue (MB), Rhodamine B (RhB) and phenol), significantly superior to Fe-N4 samples. This work is devoted to the treatment and application of natural fibers, which provides a novel method for the synthesis of SACs and the regulation of atomic coordination environment.

Keywords

iron single atomatomic regulationnatural fiberFenton-like catalysis

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Nano Research
Volume 16 Issue 7,
July 2023
Pages 9003-9011
DOI: 10.1007/s12274-023-5661-7
Cite this article:
Sun Z, Wei Y, Cao T, et al. Natural keratin-based Fe-S1N3 single atom catalyst for insights into the coordination regulation effect of Fenton-like catalysis with high efficiency. Nano Research, 2023, 16(7): 9003-9011. https://doi.org/10.1007/s12274-023-5661-7
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Photocatalysts

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Received: 06 February 2023
Revised: 02 March 2023
Accepted: 09 March 2023
Published: 02 April 2023
© Tsinghua University Press 2023
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