fig14

From: A review of the preparation and characterization techniques for closed pores in hard carbon and their functions in sodium-ion batteries

Figure 14. XPS profiles of different HC anodes: (A) Ex situ XPS Na 1s spectrum profiles of HCT1300 and Na metal after etching 60 nm^[162] (Copyright 2016, WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). (B) Ex situ XPS Na 1s and C 1s spectra depth profiles of HC after full sodiation^[32] (Copyright 2021, Wiley-VCH GmbH). (C) Na 1s X‐ray photoelectron spectroscopy spectra for the CMGL-Na electrodes test at different cut‐off voltages^[47] (Copyright 2021, Wenzhou University and John Wiley & Sons Australia, Ltd). (D) Ex situ XPS Na 1s spectra of CAC1300 electrode at various potential states^[149] (Copyright 2022, Wiley-VCH GmbH). (E) Na 1s of HCM-1300-ZBEat different voltages^[142] (Copyright 2022, Wiley-VC).