Tough Transient Ionic Junctions Printed with Ionic Microgels

摘要

Emerging soft ionotronics better match the human body mechanically andelectrically compared to conventional rigid electronics. They hold great potentialfor human-machine interfaces, wearable and implantable devices, andsoft machines. Among various ionotronic devices, ionic junctions play criticalroles in rectifying currents as electrical p–n junctions. Existing ionic junctions,however, are limited in electrical and mechanical performance, and are difficultto fabricate and degrade. Herein, the design, fabrication, and characterizationof tough transient ionic junctions fabricated via 3D ionic microgel printingis reported. The 3D printing method demonstrates excellent printability andallows one to fabricate ionic junctions of various configurations with highfidelity. By combining ionic microgels, degradable networks, and highly chargedbiopolymers, the ionic junctions feature high stretchability (stretch limit 27),high fracture energy (>1000 Jm~(?2)), excellent electrical performance (currentrectification ratio >100), and transient stability (degrade in 1 week). A variety ofionotronic devices, including ionic diodes, ionic bipolar junction transistors,ionic full-wave rectifiers, and ionic touchpads are further demonstrated. Thisstudy merges ionotronics, 3D printing, and degradable hydrogels, and willmotivate the future development of high-performance transient ionotronics.