Influence of the negative potential of molybdenum carbide derived carbon electrode on the in situ synchrotron radiation activated X-ray photoelectron spectra of 1-ethyl-3-methylimidazolium tetrafluoroborate

• Published in: Electrochimica acta 2016-07, Vol.206, p.419-426
• Main Authors: Kruusma, J., Tõnisoo, A., Pärna, R., Nõmmiste, E., Tallo, I., Romann, T., Lust, E.
• Format: Article
• Language: English
• Subjects: Carbide derived carbon; Carbon; Electrode materials; Electrode materials for electrical double layer capacitors; Electrodes; in situ X-ray photoelectron spectroscopy; Micromesoporous carbon; Room-temperature ionic liquid; Spectra; Synchrotron radiation; Wire; X-ray photoelectron spectroscopy; X-rays
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2015.10.060

Negatively charged 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) | Mo2C derived micro-mesoporous carbon (C) electrode interface has been studied using in situ synchrotron radiation initiated X-ray photoelectron spectroscopy (XPS) in order to estimate true potentials when slow electrochemical processes start at the C electrode used in the supercapacitors. A three-electrode system within the very wide working electrode (WE) potential region down to -1.90V (vs. Ag/AgCl wire in EMImBF4) has been used for the polarization of the C WE during the in situ XPS measurements. Parallel to XPS measurements in high vacuum chamber, the cyclic voltammetry measurements in the three-electrode system were carried out in the Ar-filled glovebox in order to obtain electrochemical data down to -2.40V (vs. Ag/AgCl wire in EMImBF4) for studied C electrode material. WE potential vs. XPS spectra relationship has been established and discussed here.