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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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Bimetallic Rod‐Packing Metal–Organic Framework Combining Two Charged Forms of 2‐Hydroxyterephthalic Acid
Abstract Although many rod‐packing metal‐organic frameworks are known, few are based on ordered heterometallic rod building unit. We show here the synthesis of CPM‐76 based on an unprecedented Zn‐Mg bimetallic rod with crystallographically distinguishable metal sites. The configuration of the rod offers two types of coordination site with trigonal bipyramidal and octahedral sites selectively occupied by Zn and Mg, respectively. Also unusual is the inter‐connection mode between the rods, which is based on dual‐charged forms (−3 and −2) of the 2‐hydroxyterephthalic acid (H3OBDC) ligand. Interestingly, each metal site in CPM‐76 binds one solvent molecule, leading to a high density of solvent binding sites.
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- Award ID(s):
- 1708850
- PAR ID:
- 10181932
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 26
- Issue:
- 49
- ISSN:
- 0947-6539
- Format(s):
- Medium: X Size: p. 11146-11149
- Size(s):
- p. 11146-11149
- Sponsoring Org:
- National Science Foundation
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