Deconvoluting the XPS spectra for nitrogen-doped chars: An analysis from first principles
Deconvoluting the XPS spectra for nitrogen-doped chars: An analysis from first principles
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DOI：
10.1016/j.carbon.2020.02.065
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发表时间：
2020-06-01
期刊：
影响因子：
10.9
通讯作者：
Garcia-Perez, Manuel
中科院分区：
文献类型：
--
作者：
Ayiania, Michael;Smith, Matthew;Garcia-Perez, Manuel
由于文献中的信息有限，通过 C 1s X 射线光电子 (XPS) 光谱的解卷积来量化非晶氮掺杂碳中表面含氮和氧的官能团的含量仍然很困难。为了改进氮掺杂碳的 XPS 光谱的解释，通过 DFT 计算了各种氮化碳结构的 C 1s、N 1s 和 O 1s 核心能级能级变化。此外，我们提出了一种扩展方法，以提高基于七峰 C 1s 反卷积（3 个 C-C 峰、3 个 C -N/-O 峰和 pi-pi* 跃迁峰）的 XPS 解释的自一致性。通过 DFT 计算，可以将表面缺陷碳产生的光谱成分与芳香族 sp(2) 碳区分开来。所提出的反卷积方法提供的 C/(N + O) 比率与从总 C 1s、N 1s 和 O 1s 峰获得的比率非常一致（误差小于 5%）。我们的反卷积策略为在仔细评估实验条件和结果的基础上获得高质量的实验数据拟合提供了简单的指导。 (C) 2020 Elsevier Ltd. 保留所有权利。
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 pi-pi* transition peaks). With the DFT calculations, spectral components arising from surface-defect carbons could be distinguished from aromatic sp(2) 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. (C) 2020 Elsevier Ltd. All rights reserved.