Silver nanoparticles prepared by solid-state redox route from HEC for conductive, long-term durable and recycling artificial soft electronics

Abstract The conductivity, high mechanical strength, long-term durability and recycle properties are vital roles for the flexible electronics. However, it's difficult to prepare a material with the balanced above properties. Here, the hydrogels are synthesized by hydroxyethyl cellulose/silver nanoparticles (HEC-Silver NPs), polyvinyl alcohol (PVA) and Glycerol-water as the binary solvent. Impressively, the HEC can improve the moisturizing property of the Glycerol-water for PVA hydrogel (Water retention after 7 days rise from 69.51% to 83.32%). In addition, the hydrogen bond between the HEC-Silver nanoparticles and PVA matrix can simultaneously improve tensile strength (from 0.65 MPa to 1.46 MPa) and elongation (from 541.91% to 680.53% at 25 °C). The conductive hydrogel was applied in the temperature sensor (low responsive time = 0.3s) and strain sensor (Gauge Factor = 2.36) for monitoring the joint movement. In short, biologically inspired hydrogels can be reshaped for reuse and used as bioelectronics to detect biological signals in harsh environments.