Synergistic design of a deep eutectic solvent-based conductive hydrogel enabled by Al3+ coordination and MXene integration for flexible sensing

Abstract

Deep eutectic solvent (DES)-based conductive hydrogels are attractive for flexible sensing applications due to their intrinsic ionic conductivity and environmental adaptability. However, the simultaneous optimization of mechanical robustness, self-healing capability, and electrical conductivity remains challenging because increased crosslink density often compromises charge transport. In this work, a conductive hydrogel is designed through the synergistic integration of Al³⁺ coordination and MXene nanosheets within a DES-based polymer network. Dynamic coordination interactions introduced by Al³⁺ ions enhance the mechanical strength and enable intrinsic self-healing behavior. Meanwhile, the incorporation of MXene nanosheets facilitates the formation of an ion–electron dual-conductive network, effectively compensating for the conductivity loss associated with network densification. The effects of Al³⁺ content and MXene incorporation on the hydrogel's mechanical properties, self-healing performance, and electrical conductivity are systematically investigated. The resulting hydrogel exhibits stable electrical responses under repeated mechanical deformation, demonstrating its suitability for flexible sensing applications.