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Abstract Redox‐active anthraquinone molecules represent promising anolyte materials in aqueous organic redox flow batteries (AORFBs). However, the chemical stability issue and corrosion nature of anthraquinone‐based anolytes in reported acidic and alkaline AORFBs constitute a roadblock for their practical applications in energy storage. A feasible strategy to overcome these issues is migrating to pH‐neutral conditions and employing soluble AQDS salts. Herein, we report the 9,10‐anthraquinone‐2,7‐disulfonic diammonium saltAQDS(NH4)2, as an anolyte material for pH‐neutral AORFBs with solubility of 1.9 min water, which is more than 3 times that of the corresponding sodium salt. Paired with an NH4I catholyte, the resulting pH‐neutral AORFB with an energy density of 12.5 Wh L−1displayed outstanding cycling stability over 300 cycles. Even at the pH‐neutral condition, theAQDS(NH4)2 /NH4I AORFB delivered an impressive energy efficiency of 70.6 % at 60 mA cm−2and a high power density of 91.5 mW cm−2at 100 % SOC. The present AQDS(NH4)2flow battery chemistry opens a new avenue to apply anthraquinone molecules in developing low‐cost and benign pH‐neutral flow batteries for scalable energy storage.
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Partitioning of Ambient Organic Gases to Inorganic Salt Solutions: Influence of Salt Identity, Ionic Strength, and pH
Abstract Inorganic salts present in the atmosphere may affect the composition and abundance of secondary organic aerosol. Here, we quantify the effects of salt identity, salt concentration (ionic strength), and solution pH on the partitioning of ambient water‐soluble organic gases (WSOCg) at a site in the eastern United States. The experimental pH (pH = 1–6) and ionic strengths (10−3–101 mol kg−1) span a wide range of conditions found in atmospheric particles, clouds, and fog droplets. Chloride salts (NaCl, NH4Cl, and KCl) exhibit a strong salting‐out effect at all ionic strengths >0.005 mol kg−1and pH = 1.8–6. In contrast, sulfate salts (Na2SO4, (NH4)2SO4, and K2SO4) induce both salting‐in and salting‐out behaviors, depending on ionic strength and pH. These results suggest that monovalent cations have minimal effect, while ionic strength, pH, and anion identity exert strong effects on the partitioning of ambient organic gases in the atmosphere.
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- PAR ID:
- 10444992
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 48
- Issue:
- 24
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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