Volume 60, Issue 52 pp. 27039-27045
Research Article

Development of High Energy Density Diaminocyclopropenium-Phenothiazine Hybrid Catholytes for Non-Aqueous Redox Flow Batteries

Yichao Yan

Yichao Yan

Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, MI, 48109 USA

Joint Center for Energy Storage Research (JCESR), 9700 South Cass Avenue, Argonne, IL, 60439 USA

Search for more papers by this author
Dr. David B. Vogt

Dr. David B. Vogt

Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT, 84112 USA

Joint Center for Energy Storage Research (JCESR), 9700 South Cass Avenue, Argonne, IL, 60439 USA

Search for more papers by this author
Dr. Thomas P. Vaid

Dr. Thomas P. Vaid

Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, MI, 48109 USA

Joint Center for Energy Storage Research (JCESR), 9700 South Cass Avenue, Argonne, IL, 60439 USA

Search for more papers by this author
Prof. Matthew S. Sigman

Prof. Matthew S. Sigman

Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT, 84112 USA

Joint Center for Energy Storage Research (JCESR), 9700 South Cass Avenue, Argonne, IL, 60439 USA

Search for more papers by this author
Prof. Melanie S. Sanford

Corresponding Author

Prof. Melanie S. Sanford

Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, MI, 48109 USA

Joint Center for Energy Storage Research (JCESR), 9700 South Cass Avenue, Argonne, IL, 60439 USA

Search for more papers by this author
First published: 20 October 2021
Citations: 36

Graphical Abstract

Through rational molecular design, simple chemical synthesis, and structure–property computation analysis, a new catholyte with high potential, two-electron transfer, and high solubility is developed for non-aqueous redox flow batteries.

Abstract

This report describes the design of diaminocyclopropenium-phenothiazine hybrid catholytes for non-aqueous redox flow batteries. The molecules are synthesized in a rapid and modular fashion by appending a diaminocyclopropenium (DAC) substituent to the nitrogen of the phenothiazine. Combining a versatile C-N coupling protocol (which provides access to diverse derivatives) with computation and structure-property analysis enabled the identification of a catholyte that displays stable two-electron cycling at potentials of 0.64 and 1.00 V vs. Fc/Fc+ as well as high solubility in all oxidation states (≥0.45 M in TBAPF6/MeCN). This catholyte was deployed in a high energy density two-electron RFB, exhibiting >90 % capacity retention over 266 hours of flow cell cycling at >0.5 M electron concentration.

Conflict of interest

The authors declare no conflict of interest.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.