1. Characterization of electrochemical processes in metal-organic batteries by X-ray Raman spectroscopyAva Rajh, Iztok Arčon, Klemen Bučar, Matjaž Žitnik, Marko Petric, Alen Vižintin, Jan Bitenc, Urban Košir, Robert Dominko, Hlynur Gretarsson, Martin Sundermann, Matjaž Kavčič, 2022, izvirni znanstveni članek Opis: X-ray Raman spectroscopy (XRS) is an emerging
spectroscopic technique that utilizes inelastic scattering of hard Xrays
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. Ključne besede: X-ray Raman spectroscopy, meta-organic batteries, oxygen K-edge XANES, electrochemical processes Objavljeno v RUNG: 24.03.2022; Ogledov: 2466; Prenosov: 21 Povezava na celotno besedilo Gradivo ima več datotek! Več... |