Fully physically crosslinked, recyclable and ionically conductive composite hydrogels containing metal-organic framework and their performances in soft electronic devices

This is the authors' abstract. We don't add key points for this paper.

Ionically conductive hydrogels (ICHs) show great potential in soft electronic devices, but their performances in hydrogel devices are often limited. Herein, ionically conductive composite hydrogels containing metal-organic frameworks (MOFs) are fabricated and their performances in soft electronic devices are investigated. The target composite hydrogels are fully physically crosslinked and prepared utilizing polyvinyl alcohol (PVA), sodium polyacrylate (PAANa), MOFs (e.g., ZIF-8) and zinc salt. Optimized composite hydrogels exhibit a conductivity of 1.5 S·m −1 , a fracture strength of 0.47 MPa and an elongation at break of 370 %. Notably, recycling of composite hydrogels leads to a remarkable enhancement in mechanical properties (fracture strength, 1.8 MPa; elongation at break, 445 %). Such composite hydrogels are promising as soft mechanosensors exhibiting high sensitivity (strain: 1.95, pressure: 0.40 kPa −1 ) for monitoring mechanical stimuli in daily life. Furthermore, zinc-ion hybrid supercapacitors containing such composite hydrogel electrolytes achieve high cycling stability in over 4100 cycles (current density: 1 A·g −1 ) with negligible capacity fading. Overall, composite hydrogels containing MOFs are expected to serve as promising materials for next-generation soft electronic devices.