Constructing Quasi-Single-Ion-Conductive Organic/Inorganic Artificial Interfacial Layer for Stable Zinc Electrodeposition

The performance and lifespan of zinc-ion energy storage devices are significantly hindered by dendrite growth and side reactions at the zinc anode. This work proposes and constructs a quasi-single-ion-conductive organic/inorganic artificial interfacial layer, combining sulfonated polyether ether ketone (SPEEK) with hydroxyapatite (HAP) nanowires, to stabilize zinc anodes. By regulating Zn²⁺ migration channels and blocking SO₄^2– and H₂O molecules, such a SPEEK/HAP layer enables highly efficient and stable zinc electrodeposition. Experimental results demonstrate that symmetric cells with the SPEEK/HAP-coated anode achieve stable cycling for over 660 h at 1 mA cm^–2 and 0.5 mAh cm^–2. The Zn||MnO₂ full cell retains 64.5% capacity after 6000 cycles at 2 A g^–1, and the zinc-ion hybrid capacitor maintains 88.96% initial capacity after 30,000 cycles at 5 A g^–1. This interfacial engineering strategy, featuring quasi-single-ion-conductive channels, offers a promising approach for optimizing zinc anodes and advancing high-performance zinc-based energy storage technologies.