![xps peak pure sulphur s2p xps peak pure sulphur s2p](https://www.degruyter.com/document/doi/10.1515/ntrev-2021-0005/asset/graphic/j_ntrev-2021-0005_fig_004.jpg)
However, accessing the deeply buried solid-electrolyte interfaces (which dictates the performance of energy storage devices) has been a challenge in XPS usage. Spectra result from within the top 10 nm of the surface, which allows XPS to focus on the crucial surface area. XPS is an extremely surface-sensitive technique, too.
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Samples are analyzed under vacuum, and so surface changes during the analysis are kept to a minimum. X-ray photoelectron spectroscopy (XPS) - a powerful surface analysis tool - has been widely used to study these energy storage materials because of its ability to identify, quantify and image the chemical distribution of redox active species. In particular the spectra recorded on the S2p and S KLL lines of the sulphides and sulphates are shown: they were collected for getting the peak fitting parameters and apply them to the model systems obtained by mixing sulphur with sodium tetrasulphide and to investigate the composition of mineral surfaces. XPS is an excellent technique for this type of characterization.
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Material complexities associated with these energy storage devices with unique electrochemistry are formidable challenge which needs to be address for transformative progress in this field. XPS results also suggest that introducing BChE eliminates the satellite peaks of CuO, located at 962.5, 954.1, 944.0, and 942. Wide range of energy storage devices, Redox-flow batteries (RFB), Lithium ion based batteries (LIB), and Lithium-sulfur (LSB) batteries are being developed for various applications ranging from grid-scale level storage to mobile electronics. The single step transformation of sulphur to Li 2 S 2 /Li 2 S and vice-versa during the discharge/charge process is explained by analyzing the subsurface using XPS. Technological development requires reliable power sources where energy storage devices are emerging as a critical component.