TY - JOUR
T1 - Deconvoluting the XPS spectra for nitrogen-doped chars
T2 - An analysis from first principles
AU - Ayiania, Michael
AU - Smith, Matthew
AU - Hensley, Alyssa J.R.
AU - Scudiero, Louis
AU - McEwen, Jean Sabin
AU - Garcia-Perez, Manuel
N1 - Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/6
Y1 - 2020/6
N2 - Quantifying the content of surface nitrogen and oxygen containing functional groups in amorphous nitrogen doped carbons via deconvolution of C 1s x-ray photoelectron (XPS) spectra remains difficult due to limited information in the literature. To improve the interpretation of XPS spectra of nitrogen-doped carbons, the C 1s, N 1s and O 1s core level energy shifts have been calculated for various nitrogenated carbon structures via DFT. Furthermore, we propose an expanded method to improve the self-consistency of the XPS interpretation based on a seven-peak C 1s deconvolution (3 C–C peaks, 3 C–N/-O peaks, and π-π∗ transition peaks). With the DFT calculations, spectral components arising from surface-defect carbons could be distinguished from aromatic sp2 carbon. The deconvolution method proposed provides C/(N + O) ratios in very good agreement (error less than 5%) with those obtained from total C 1s, N 1s and O 1s peaks. Our deconvolution strategy provides a simple guideline for obtaining high-quality fits to experimental data on the basis of a careful evaluation of experimental conditions and results.
AB - Quantifying the content of surface nitrogen and oxygen containing functional groups in amorphous nitrogen doped carbons via deconvolution of C 1s x-ray photoelectron (XPS) spectra remains difficult due to limited information in the literature. To improve the interpretation of XPS spectra of nitrogen-doped carbons, the C 1s, N 1s and O 1s core level energy shifts have been calculated for various nitrogenated carbon structures via DFT. Furthermore, we propose an expanded method to improve the self-consistency of the XPS interpretation based on a seven-peak C 1s deconvolution (3 C–C peaks, 3 C–N/-O peaks, and π-π∗ transition peaks). With the DFT calculations, spectral components arising from surface-defect carbons could be distinguished from aromatic sp2 carbon. The deconvolution method proposed provides C/(N + O) ratios in very good agreement (error less than 5%) with those obtained from total C 1s, N 1s and O 1s peaks. Our deconvolution strategy provides a simple guideline for obtaining high-quality fits to experimental data on the basis of a careful evaluation of experimental conditions and results.
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U2 - 10.1016/j.carbon.2020.02.065
DO - 10.1016/j.carbon.2020.02.065
M3 - Article
AN - SCOPUS:85081011423
SN - 0008-6223
VL - 162
SP - 528
EP - 544
JO - Carbon
JF - Carbon
ER -