Journal Article

FZJ-2023-05474

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png An oxo-verdazyl radical for a symmetrical nonaqueous redox flow battery

Korshunov, A. ; Milner, M. J. ; Grünebaum, M.FZJ* ; Studer, A. ; Winter, M. (Corresponding author)FZJ* ; Cekic-Laskovic, I. (Corresponding author)FZJ*

2020
RSC London ˜[u.a.]œ

Abstract: Verdazyl free radical compounds are promising candidates for symmetrical all-organic redox flow batteries(RFBs) due to their redox stability, the ease with which their chemical structure can be varied, and theirunique bipolar nature. The present work reports a preliminary screening of a selection of oxo-verdazylcompounds for key redox electrolyte parameters. Of the considered candidates, the 1,5-diphenyl-3-isopropyl-6-oxo-verdazyl radical performed best and is investigated in extensive RFB experiments tocompare its electrochemical behavior in cyclic voltammetry (CV) to that within an actual battery. Thesymmetrical oxo-verdazyl non-aqueous electrolyte RFB provides a mean voltage of 1.42 V anddemonstrates good stability as well as high coulombic (>97%) and energy efficiencies over more than100 charge/discharge cycles. The redox electrolyte is characterized at different stages within a singlecycle (‘state of charge’ experiments) independently for each half-cell. To address the specifics of theelectrolyte transition to RFB cell setup an ‘in-cell’ CV flow-enabled electrochemical study has beenconducted, introduced here as a new step towards standardization of the electrochemical description ofRFB electrolytes. The electrochemical performance results highlight oxo-verdazyls as versatile materialsfor energy applications and indicate great promise for their further development and optimization in thefield of RFBs.

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Contributing Institute(s):

1. Helmholtz-Institut Münster Ionenleiter für Energiespeicher (IEK-12)

Research Program(s):

1. 1221 - Fundamentals and Materials (POF4-122) (POF4-122)
2. SFB 858 B11 - Kooperativität in organischen spintragenden Materialien und ihren Hybridsystemen: Steuerung magnetischer Eigenschaften durch Orientierung von Radikalen (B11) (159705466) (159705466)

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Engineering, Computing and Technology ; Current Contents - Physical, Chemical and Earth Sciences ; Essential Science Indicators ; IF >= 10 ; JCR ; National-Konsortium ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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