Design and Synergistic Effects of Ionic Liquid-MoS₂ Composite Hydrogels for Enhanced Conductivity and Adhesion

Abstract

Hydrogels are still limited by insufficient mechanical strength and poor electrical conductivity. To address these challenges, it is essential to develop versatile hydrogels that integrate strong adhesion, high conductivity, and robust mechanical performance. In this study, a multifunctional hydrogel system is synthesized via free radical polymerization using 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and acrylic acid (AA). We employed dually ionic-exfoliated MoS2 (MoS₂) as a conductive filler to fabricate a multifunctional hydrogel with both conductivity and adhesiveness. A dynamic hydrogen-bonding network is established using A-T and G-C base pair mimics, while a synergistic combination of short-chain (C4) and long-chain (C12) imidazole-based ionic liquids facilitated the exfoliation and stabilization of MoS2. This method facilitates uniform dispersion of MoS₂ and reinforces interfacial bonding within the hydrogel matrix. The resulting A-PS-A0.05-T0.05/G0.35-C0.35-ILs@MoS2 hydrogels demonstrate outstanding mechanical properties, achieving a tensile stress of 36.53 kPa and a strain of 2543.39%. Furthermore, the hydrogels exhibit remarkable sensing performance, including high sensitivity (GF = 5.45), a rapid response time of 300 ms, and an adhesion strength of up to 5.9 kPa across a wide strain range.