High-performance anthraquinone with potentially low cost for aqueous redox flow batteries. Issue 47 (23rd November 2021)

• Record Type: Journal Article
• Authors: Wu, Min; Bahari, Meisam; Fell, Eric M.; Gordon, Roy G.; Aziz, Michael J.
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 47(2021)
• Page Start: 26709
• Page End: 26716
• Publication Date: 2021-11-23
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta08900e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Alkaline anthraquinone flow battery with active species exhibiting long lifetime and potentially low mass-production cost. Abstract : Electrolyte cost and long-term durability are the two most challenging obstacles to the practical utilization of redox-active organics in aqueous redox flow batteries. Starting from potentially inexpensive 1, 8-dihydroxyanthraquinone (1, 8-DHAQ), we developed a one-pot, green, and scalable approach to synthesize a highly water-soluble and potentially low-cost anthraquinone 1, 8-dihydroxy-2, 7-dicarboxymethyl-9, 10-anthraquinone (DCDHAQ). The demonstrated volumetric capacity of DCDHAQ in 1 M KOH is 40.2 A h L −1, which is around 70 times higher than that of its precursor 1, 8-DHAQ (0.567 A h L −1 ) at pH 14. The introduction of –CH2 CO2 − as solubilizing groups suppressed the disproportionation reaction of reduced anthraquinone both thermodynamically and kinetically. Consequently, the cycling stability of anthraquinone was improved significantly compared to that of the precursor. Pairing a negolyte comprising 0.75 M DCDHAQ with a posolyte comprising 0.3 M ferrocyanide at pH 14, we demonstrated a cell with an open-circuit voltage of 1.1 V and a low capacity fade rate of 0.03% per day. The synthetic method of attaching –CH2 CO2 − as solubilizing groups is likely applicable to other anthraquinone derivatives and other aromatic organics as an inexpensive approach to performance enhancement in energy applications.