Modification of conventional peak shapes to accurately represent spectral asymmetry: High-Resolution X-ray photoelectron spectra of [C4C1Pyrr][NTf2] and [C8C1Im][NTf2] ionic liquids
Modification of conventional peak shapes to accurately represent spectral asymmetry: High-Resolution X-ray photoelectron spectra of [C4C1Pyrr][NTf2] and [C8C1Im][NTf2] ionic liquids
复制标题
修改传统峰形以准确表示光谱不对称性：[C4C1Pyrr][NTf2] 和 [C8C1Im][NTf2] 离子液体的高分辨率 X 射线光电子能谱
DOI：
10.1016/j.apsusc.2022.155314
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发表时间：
2023
影响因子：
6.7
通讯作者：
Smith E
中科院分区：
文献类型：
--
作者：
Smith E
X射线光电子能谱（XPS）是用于表面表征的最广泛使用的技术之一。XPS数据的分析具有挑战性，需要分析人员将数据与合成线形状拟合，以获得物理上有意义的解释。然而，实验光谱包络很复杂，并且显示出不对称特征，这些特征通常被忽视或归因于其他化学成分。[C4C1Pyrr][NTf2]和[C8C1Im][NTf2]的高分辨率XPS谱都表现出一定程度的不对称性，这在光电子能包络的较高结合能侧被系统地观察到。我们提出了一个完善的拟合程序的XPS光谱的这些离子液体为基础的系统，其中包括（a）雪莉背景偏移，以占绝缘体样区域和（B）光谱不对称性在C 1s和N 1s区域的发展。此外，雪莉和梯形组件被施加到补偿非弹性散射发生在电子跃迁高达7.8 eV以上的开始在C 1s的高分辨率光谱的拟合区域。为了证明该模型的适用性，我们分析了[C4C1Pyrr][NTf2]：[C8C1Im][NTf2]的2：1混合物。
X-ray photoelectron spectroscopy (XPS) is one of the most widely used techniques for surface characterization. Analysis of XPS data is challenging and requires the analyst to fit the data with synthetic line shapes to reach physically meaningful interpretations. Experimental spectral envelopes, however, are complex and display asymmetric features that are often ignored or attributed to additional chemical components. The high-resolution XPS spectra of [C4C1Pyrr][NTf2] and [C8C1Im][NTf2] all exhibit a degree of asymmetry which is systematically observed at the higher binding energy side of photoemission envelopes. We present the development of a refined fitting procedure for XPS spectra of these ionic liquid-based systems which include (a) Shirley background offset necessary to account for the insulator-like region and (b) spectral asymmetry in C 1s and N 1s regions. Further, Shirley and trapezoid components are applied to compensate for inelastic scattering taking place during electron transitions as high as 7.8 eV above the start of the fitting region in C 1s high-resolution spectrum. To demonstrate the fitness of this model, we present an analysis of a 2:1 mixture of [C4C1Pyrr][NTf2]: [C8C1Im][NTf2].