Montmorillonite Nanoreactors for Synergistic Confinement Synthesis and Ion-Conduction in Stable Sulfurized Polyacrylonitrile Cathodes

Abstract

Sulfurized polyacrylonitrile (SPAN) is a promising cathode for lithium-sulfur batteries, yet its practical application is hindered by structural degradation under long-term cycling at high rates. Herein, we report a synergistic nanoconfinement strategy using montmorillonite (MMT) lamellae as nanoreactors for the in-situ polymerization of acrylonitrile and subsequent sulfurization. This approach not only stabilizes the SPAN structure but also leverages the innate interlayer galleries of MMT as efficient lithium-ion transport channels. The resulting SPAN/MMT cathode delivers exceptional cycling stability with a capacity decay rate of only 0.014% per cycle over 5000 cycles at a high current density of 3 A g-1. This work highlights the potential of nanoconfinement engineering for developing advanced electrode materials.