Self-Healing Bimodal Sensors Based on Bioderived Polymerizable Deep Eutectic Solvent Ionic Elastomers

Abstract

Despite the remarkable progress in electronic skins (e-skins), it remains a great challenge to achieve high biocompatibility, multimodal response, and self-healing abilities simultaneously. Here, a fully biobased self-healing bimodal sensor based on the polymerizable deep eutectic solvent (PDES) ionic elastomer is elaborately constructed for skin-contact multifunctional e-skin applications. Utilizing the synergistic regulation of physical and hydrogen bonding networks constructed by the polydopamine-coated cellulose nanocrystal, the bioderived PDES breaks the limitations of general biobased materials in strength and toughness while possessing excellent self-healing properties. The resulting ionic elastomer exhibits outstanding biocompatibility (cell viability over 87%), excellent autonomous self-healing efficiency (>90%), and superior mechanical properties (2.95 and 69.57 times higher tensile strength and toughness than pure bioderived PDES). Furthermore, intrinsic ionic migration within the PDES and the pH-responsive property of the anthocyanin coating enable the sensor to bimodally detect human motion and sweat physiological information visualization, with a stable electrical output signal and a wide sweat visualization range (pH 3–12) both before and after self-healing. This work provides new perspectives for the future skin-contact and implantable bioelectronics in medical diagnostics and healthcare.