Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars

To address the problem of variability in in situ Raman spectroscopy for determining the chemical structure of chars, the rationality of Raman’s original peak spectrum fitting method, the influence of objective lens magnification, particle size, and number of measurements on peak shape and characteri...

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Main Authors: Jiangyong He, Chong Zou, Junxue Zhao, Jiale Xi, Yuan She, Mengmeng Ren, Yufen Xu
Format: Article
Language:English
Published: MDPI AG 2022-08-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/15/15/5627
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author Jiangyong He
Chong Zou
Junxue Zhao
Jiale Xi
Yuan She
Mengmeng Ren
Yufen Xu
author_facet Jiangyong He
Chong Zou
Junxue Zhao
Jiale Xi
Yuan She
Mengmeng Ren
Yufen Xu
author_sort Jiangyong He
collection DOAJ
description To address the problem of variability in in situ Raman spectroscopy for determining the chemical structure of chars, the rationality of Raman’s original peak spectrum fitting method, the influence of objective lens magnification, particle size, and number of measurements on peak shape and characteristic parameters were investigated. The results show that the Raman original peak spectrum of char is fitted by five peaks and the goodness of fit is best when the D3 peak is fitted by a Gaussian curve. The intensity of the peak spectrum and stability of the characteristic parameters of the Raman spectroscopy are related to the objective lens magnification. For a relatively large objective lens magnification, the Raman peak spectrum intensity is increased and the coefficient of variation in the characteristic parameters is accordingly reduced. As particle size increases, the characteristic parameters A<sub>G</sub>/A<sub>All</sub> that characterize the perfect graphite structure decrease and the characteristic parameters A<sub>D1</sub>/A<sub>All</sub>, A<sub>D3</sub>/A<sub>All</sub>, and A<sub>D1</sub>/A<sub>G</sub> that characterize the defective graphite structure increase. The coefficient of variation for the characteristic parameters is found to be the smallest for the particle size range of 81–96 μm. Micro-Raman imaging reveals that the microscopic characteristic parameters of different micro zones are significantly different and the number of measurements required to achieve reliable Raman characteristic parameters is related to this anisotropy.
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spelling doaj.art-924cfb203cc441929f75dc85e908094d2023-11-30T22:20:28ZengMDPI AGEnergies1996-10732022-08-011515562710.3390/en15155627Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of CharsJiangyong He0Chong Zou1Junxue Zhao2Jiale Xi3Yuan She4Mengmeng Ren5Yufen Xu6School of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaSchool of Metallurgical Engineering, Xi’an University of Architecture and Technology, Xi’an 710311, ChinaTo address the problem of variability in in situ Raman spectroscopy for determining the chemical structure of chars, the rationality of Raman’s original peak spectrum fitting method, the influence of objective lens magnification, particle size, and number of measurements on peak shape and characteristic parameters were investigated. The results show that the Raman original peak spectrum of char is fitted by five peaks and the goodness of fit is best when the D3 peak is fitted by a Gaussian curve. The intensity of the peak spectrum and stability of the characteristic parameters of the Raman spectroscopy are related to the objective lens magnification. For a relatively large objective lens magnification, the Raman peak spectrum intensity is increased and the coefficient of variation in the characteristic parameters is accordingly reduced. As particle size increases, the characteristic parameters A<sub>G</sub>/A<sub>All</sub> that characterize the perfect graphite structure decrease and the characteristic parameters A<sub>D1</sub>/A<sub>All</sub>, A<sub>D3</sub>/A<sub>All</sub>, and A<sub>D1</sub>/A<sub>G</sub> that characterize the defective graphite structure increase. The coefficient of variation for the characteristic parameters is found to be the smallest for the particle size range of 81–96 μm. Micro-Raman imaging reveals that the microscopic characteristic parameters of different micro zones are significantly different and the number of measurements required to achieve reliable Raman characteristic parameters is related to this anisotropy.https://www.mdpi.com/1996-1073/15/15/5627Raman spectroscopycoal pyrolysischarcarbon chemical structure
spellingShingle Jiangyong He
Chong Zou
Junxue Zhao
Jiale Xi
Yuan She
Mengmeng Ren
Yufen Xu
Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
Energies
Raman spectroscopy
coal pyrolysis
char
carbon chemical structure
title Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
title_full Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
title_fullStr Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
title_full_unstemmed Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
title_short Influence of Raman Spectroscopy Test Conditions on the Results of Carbon Chemical Structure of Chars
title_sort influence of raman spectroscopy test conditions on the results of carbon chemical structure of chars
topic Raman spectroscopy
coal pyrolysis
char
carbon chemical structure
url https://www.mdpi.com/1996-1073/15/15/5627
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