A Multifunctional Cerium-Based Metal-Organic Framework Coating for Dendrite-Free and Highly Stable Zinc Metal Anodes
Aqueous zinc-ion batteries (AZIBs) face critical challenges from zinc anode instability, including corrosion, hydrogen evolution reaction (HER), parasitic byproduct formation, and uncontrolled dendrite growth. To address these issues, we developed a multifunctional cerium-based metal-organic framework (Ce-MOF) coating for zinc anodes. The coating features an ordered porous structure and inherent properties that mitigate HER, suppress side reactions, and inhibit dendrite formation. Symmetric cells using Ce-MOF/Zn demonstrated exceptional cycling stability for over 2060 h at 0.5 mA cm−2 with a low hysteresis polarization of 26 mV. In full cells with an I2@AC cathode, the Ce-MOF/Zn||I2@AC achieved outstanding cycling stability of 28,550 cycles at 5 A g−1, with 91% capacity retention (109.6 mAh g−1). Through integrated characterization employing in-situ optical microscopy, ex-situ XRD, SEM, and DFT calculations, we elucidated the multifunctional mechanism: the Ce-MOF coating facilitates preferential (002)-oriented Zn deposition to suppress dendrites, reduces Zn2+ desolvation energy to enhance deposition kinetics, and modulates interfacial chemistry to mitigate HER and corrosion. This work establishes Ce-MOF coatings as a simple yet powerful strategy for developing high-performance zinc anodes, providing critical insights for advancing practical AZIB technologies.