气候变化领域集成服务门户(CCPortal): Evolution of Zn(II) single atom catalyst sites during the pyrolysis-induced transformation of ZIF-8 to N-doped carbons

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DOI	10.1016/j.scib.2020.06.020
	Evolution of Zn(II) single atom catalyst sites during the pyrolysis-induced transformation of ZIF-8 to N-doped carbons
	Wang Q.; Ina T.; Chen W.-T.; Shang L.; Sun F.; Wei S.; Sun-Waterhouse D.; Telfer S.G.; Zhang T.; Waterhouse G.I.N.
发表日期	2020
ISSN	20959273
起始页码	1743
结束页码	1751
卷号	65 期号:20
英文摘要	The pyrolysis of zeolitic imidazolate frameworks (ZIFs) is becoming a popular approach for the synthesis of catalysts comprising porphyrin-like metal single atom catalysts (SACs) on N-doped carbons (M-N-C). Understanding the structural evolution of M-N-C as a function of ZIF pyrolysis temperature is important for realizing high performance catalysts. Herein, we report a detailed investigation of the evolution of Zn single atom catalyst sites during the pyrolysis of ZIF-8 at temperatures ranging from 500 to 900 °C. Results from Zn L-edge and Zn K-edge X-ray absorption spectroscopy studies reveal that tetrahedral ZnN4 centers in ZIF-8 transform to porphyrin-like ZnN4 centers supported on N-doped carbon at temperatures as low as 600 °C. As the pyrolysis temperature increased in the range 600–900 °C, the Zn atoms moved closer to the N4 coordination plane. This subtle geometry change in the ZnN4 sites alters the electron density on the Zn atoms (formally Zn2+), strongly impacting the catalytic performance for the peroxidase-like decomposition of H2O2. The catalyst obtained at 800 °C (Zn-N-C-800) offered the best performance for H2O2 decomposition. This work provides valuable new insights about the evolution of porphyrin-like single metal sites on N-doped carbons from ZIF precursors and the factors influencing SAC activity. © 2020 Science China Press
关键词	Metal organic frameworks Metal single atom catalysts N-doped carbon Porphyrin-like sites X-ray absorption spectroscopy
英文关键词	Atoms; Catalysts; Doping (additives); Porphyrins; Pyrolysis; X ray absorption spectroscopy; Catalyst site; Catalytic performance; Coordination plane; Geometry change; Pyrolysis temperature; Single atoms; Structural evolution; Zeolitic imidazolate frameworks; Zinc compounds
语种	英语
来源期刊	Science Bulletin
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207211
作者单位	School of Chemical Sciences, The University of Auckland, Auckland, 1142, New Zealand; Research & Utilization Division, Japan Synchrotron Radiation Research Institute, Kouto, 679-5148, Japan; Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China; Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201204, China; Department of Chemical and Materials Engineering, Faculty of Engineering, The University of Auckland, Auckland, 1142, New Zealand; MacDiarmid Institute for Advanced Materials and Nanotechnology, Massey University, Palmerston North, 4442, New Zealand
推荐引用方式 GB/T 7714	Wang Q.,Ina T.,Chen W.-T.,et al. Evolution of Zn(II) single atom catalyst sites during the pyrolysis-induced transformation of ZIF-8 to N-doped carbons[J],2020,65(20).
APA	Wang Q..,Ina T..,Chen W.-T..,Shang L..,Sun F..,...&Waterhouse G.I.N..(2020).Evolution of Zn(II) single atom catalyst sites during the pyrolysis-induced transformation of ZIF-8 to N-doped carbons.Science Bulletin,65(20).
MLA	Wang Q.,et al."Evolution of Zn(II) single atom catalyst sites during the pyrolysis-induced transformation of ZIF-8 to N-doped carbons".Science Bulletin 65.20(2020).