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Abstract It remains a challenge to design aqueous electrolytes to secure the complete reversibility of zinc metal anodes. The concentrated water‐in‐salt electrolytes, e.g., 30 m ZnCl2, are promising candidates to address the challenges of the Zn metal anode. However, the pure 30 m ZnCl2electrolyte fails to deliver a smooth surface morphology and a practically relevant Coulombic efficiency. Herein, it is reported that a small concentration of vanillin, 5 mg mLwater−1, added to 30 m ZnCl2transforms the reversibility of Zn metal anode by eliminating dendrites, lowering the Hammett acidity, and forming an effective solid electrolyte interphase. The presence of vanillin in the electrolyte enables the Zn metal anode to exhibit a high Coulombic efficiency of 99.34% at a low current density of 0.2 mA cm−2, at which the impacts of the hydrogen evolution reaction are allowed to play out. Using this new electrolyte, a full cell Zn metal battery with an anode/cathode capacity (N/P) ratio of 2:1 demonstrates no capacity fading over 800 cycles.
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This content will become publicly available on June 24, 2026
The contrasting impacts of polyethylene glycol on electrochemical behaviors of Fe and Zn metal anodes in aqueous batteries
The PEG addition into aqueous electrolytes has an opposite effect on an Fe metal anode compared to a Zn metal anode.
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- PAR ID:
- 10621562
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 61
- Issue:
- 52
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 9508 to 9511
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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