Near-Theoretical-Density Zinc Plating Enabled by an Ordered Janus Interphase for High-Energy Zinc Pouch Cells
Fengxue Duan, Junjie Ba, Mengqi Wu, Mingfeng Wei, Junpeng Li, Silong Cui, Ruqian Lian, Xiuxiu Yin, Biswarup Chakraborty, Kangning Zhao, Yingjin Wei, Yizhan WangAbstract
Achieving ultradense zinc plating at the theoretical limit is crucial for high-energy aqueous zinc metal batteries (AZMBs), but is hindered by severe interfacial instabilities such as dendrite growth and hydrogen evolution. Here we construct a nanometer-thin, vertically stratified organic–inorganic Janus bilayer (CF-LaF3) by ion layer epitaxy to pre-engineer the zinc anode interface. A hydrophobic perfluoroalkyl top layer accelerates Zn2+ desolvation, blocks active water and suppresses parasitic reactions, while a crystalline LaF3 bottom layer with high modulus, zincophilicity and continuous ionic channels homogenizes Zn2+ flux and helps mechanically suppress dendritic growth. This complementary interphase delivers dendrite-free zinc deposition at 5 mAh cm–2 with an ultradense thickness of 8.60 μm, approaching the theoretical limit (8.54 μm). Ah-level Zn||I2 pouch cells achieve 109 Wh L–1 energy density on a full-cell basis. This pre-engineered Janus interphase offers a general and scalable route to practical high-energy AZMBs.