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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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Design and analysis of polygonal mirror-based scan engines for improved spatial frequency modulation imaging
Spatialfrequency modulationimaging (SPIFI) is a structured illumination single pixel imaging technique that is most often achieved via a rotating modulation disk. This implementation produces line images with exposure times on the order of tens of milliseconds. Here, we present a new architecture for SPIFI using a polygonal scan mirror with the following advances: (1) reducing SPIFI line image exposure times by 2 orders of magnitude, (2) facet-to-facet measurement and correction for polygonal scan design, and (3) a new anamorphic magnification scheme that improves resolution for long working distance optics.
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- PAR ID:
- 10413043
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 62
- Issue:
- 15
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. 3861
- Size(s):
- Article No. 3861
- Sponsoring Org:
- National Science Foundation
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