LAUSR

Hydrogel bioelectronics as one of the next-generation wearable and implantable electronics ensure super biocompatibility and softness to bridge human body and electronics. However, volatile, opaque and fragile features of hydrogels due to the sparsely and microscale three-dimensional network, seriously limit their practical applications. Here, we report a type of smart and robust nanofibrillar polyvinyl alcohol (PVA) organohydrogels fabricated via one-step physical cross-linking. The nanofibrillar network cross-linked by numerous PVA nanocrystallites enables the formation of organohydrogels with high transparency (90%), drying resistance, high toughness (3.2 MJ/m3) and tensile strength (1.4 MPa). For strain sensor application, the PVA ionic organohydrogel after soaking NaCl solution shows excellent linear sensitivity (GF=1.56, R2 > 0.998) owing to the homogeneous nanofibrillar PVA network. We demonstrate the potential applications of the nanofibrillar PVA-based organohydrogel in smart contact lens and emotion recognition. Such a strategy paves an effective way to fabricate strong, tough, biocompatible and ionically conductive organohydrogels, shedding light on multifunctional sensing applications in next-generation flexible bioelectronics.