In Situ Growth of a Metal–Organic Framework-Based Solid Electrolyte Interphase for Highly Reversible Zn Anodes

Abstract

Aqueous Zn ion batteries are receiving tremendous attention owing to their attractive features with respect to safety, cost, and scalability, yet their lifespan is severely limited by the poor reversibility of the Zn metal anode. Thereby, an artificial solid electrolyte interphase (ASEI) based on an anionic metal−organic framework (MOF) is in situ fabricated on the surface of Zn anodes. The robust ASEI protects the anode from side reactions and largely promotes its Coulombic efficiency during battery cycling. Owing to the high intrinsic Zn 2+ conductivity and abundant zincophilic sites, it also facilitates enhanced Zn redox activities. More interestingly, the consecutive sulfonate groups in the MOF channels guide rapid and directional transport of Zn ions and thus endow a dendrite-free Zn plating/stripping lifespan of 5700 h at 2 mA cm −2 . This work provides a fresh strategy to promote the performance of Zn and even other metallic anodes toward practical battery applications.

Highly Stable Zn Anodes Modulated by Selenizing In Situ Grown Metal–Organic Frameworks

“…A smaller contact angle implies more uniform transport of Zn 2+ at the interface. 32,33 The contact angles of bare Zn, SCM@Zn, and CM@Zn reach 119.49°, 93.19°, and 101.80°, respectively (Figures 1j,k and S3). The good wettability of SCM@Zn could be attributed to the presence of CuSe decoration.…”

In‐Situ Integration of a Hydrophobic and Fast‐Zn2+‐Conductive Inorganic Interphase to Stabilize Zn Metal Anodes

“…The Zn 2+ transference number ( t $${{_{{\rm Zn}{^{2+}}}}}$$ ) is measured to evaluate the Zn 2+ diffusion ability of ZnHCF. Generally, a low t $${{_{{\rm Zn}{^{2+}}}}}$$ would induce a large Zn 2+ concentration gradient at the electrode/electrolyte interface and aggravate dendrites propagation [4d, 6a, 17] . Based on the chronoamperometry and electrochemical impedance spectroscopy (EIS) tests (Figures 5d and S20), [7a, 20b] the HB‐ZnHCF exhibits an ultrahigh t $${{_{{\rm Zn}{^{2+}}}}}$$ of 0.86, which dramatically outperforms the bare Zn ( t $${{_{{\rm Zn}{^{2+}}}}}$$ ≈0.35) and HL‐ZnHCF@Zn ( t $${{_{{\rm Zn}{^{2+}}}}}$$ ≈0.56).…”

Reducing the Surface Tension of Zn Anodes by an Abietic Acid Layer for High Redox Kinetics and Reversibility

“…Besides, the passivated surface induces inhomogeneous Zn deposition that brings the risk of dendrite growth and battery short circuit . The construction of protective layers, such as inorganics, , polymers, , alloys, , and metal–organic frameworks, − is an effective strategy to increase the reversibility of Zn anodes. They prevent the direct contact between Zn anodes and electrolytes and thus alleviate the side reactions.…”