SnS2(001)-Reinforced Ion/Molecular Sieving Separator Enables High-Performance Aqueous Zinc-Organic Batteries

Abstract

Challenges including dendrite growth on Zn anodes and organic cathode dissolution severely hinder the practical application of aqueous zinc-organic batteries (AZOBs). Herein, a Janus separator engineered by anchoring SnS₂(001) nanosheets onto glass fiber (SnS₂(001)@GF) to tackle these issues is prsented. The (001) plane orientation of SnS₂, compared to the (100) crystal plane, features reduced binding energy with Zn²⁺ and lower work function, enhancing Zn²⁺ ion diffusion, creating uniform electric field and ion concentration, and enabling preferential deposition of Zn²⁺ along the (002) direction with rapid kinetics, while concurrently repelling SO₄²⁻ ions through electrostatic repulsion. Additionally, the hierarchical stacking properties of SnS₂(001) mitigate the shuttling of organic cathodes. With this Janus separator, a robust SEI layer of ZnS, Zn₅Sn₄, and Zn₇Sn₄ forms on the Zn surface, further inhibiting Zn dendrites and byproduct formation. The Zn//Zn cell exhibits stable cyclability exceeding 2100 h at 1 mA cm⁻² and 1 mAh cm⁻². The Zn//bipolar organic molecular cathinone (IDT) full battery achieves stable electrochemical behavior over 2250 cycles at 10 A g⁻¹, with 100% capacity retention after 850 cycles at a mass loading of 17 mg cm⁻¹. Other full batteries utilizing dibenzo[b,i]thianthrene-5,7,12,14–tetraone (DTT) and 5,7,12,14–pentacenetetrone (PT) respectively demonstrate significantly enhanced electrochemical performance.