Naslov
Characterization of Electrochemical Processes in Metal–Organic Batteries by X-ray Raman Spectroscopy

Autori
Rajh, Ava ; Arčon, Iztok ; Bučar, Klemen ; Žitnik, Matjaž ; Petric, Marko ; Vizintin, Alen ; Bitenc, Jan ; Košir, Urban ; Dominko, Robert ; Gretarsson, Hlynur ; Sundermann, Martin ; Kavčič, Matjaž

Izvornik
The Journal of Physical Chemistry C (1932-7447) 126 (2022), 12; 5435-5442

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
X-ray Raman Spectroscopy, Batteries, Carbonyls, Electrodes, Oxygen

Sažetak
X-ray Raman spectroscopy (XRS) is an emerging spectroscopic technique that utilizes inelastic scattering of hard X-rays to study X-ray absorption edges of low Z elements in bulk material. It was used to identify and quantify the amount of carbonyl bonds in a cathode sample, in order to track the redox reaction inside metal–organic batteries during the charge/discharge cycle. XRS was used to record the oxygen K-edge absorption spectra of organic polymer cathodes from different multivalent metal–organic batteries. The amount of carbonyl bond in each sample was determined by modeling the oxygen K-edge XRS spectra with the linear combination of two reference compounds that mimicked the fully charged and the fully discharged phases of the battery. To interpret experimental XRS spectra, theoretical calculations of oxygen K-edge absorption spectra based on density functional theory were performed. Overall, a good agreement between the amount of carbonyl bond present during different stages of battery cycle, calculated from linear combination of standards, and the amount obtained from electrochemical characterization based on measured capacity was achieved. The electrochemical mechanism in all studied batteries was confirmed to be a reduction of double carbonyl bond and the intermediate anion was identified with the help of theoretical calculations. X-ray Raman spectroscopy of the oxygen K-edge was shown to be a viable characterization technique for accurate tracking of the redox reaction inside metal–organic batteries.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Interdisciplinarne prirodne znanosti

POVEZANOST RADA