The Polymer Society of Korea

Abstract

Ionic diodes function by directing ion flow and rectifying ionic currents have diverse applications in iontronic domains. While classic heterojunction diodes are commonly interpreted via equilibrium-based thermodynamic models, the actual behavior may be better captured by focusing on the dynamics at the interface. Here, we present a tri-layer structure ionic diode that operates kinetically by inducing a phase transition through the application of the external voltage. By electrically modulating ion transport, we induce a phase transition in ion-sensitive layers—polyelectrolyte complex and plastic crystal—leading to kinetic and electrical property changes. This transition dictates that both heterojunction and tri-layer structures share the same fundamental mechanism. Our results highlight that kinetic control of ion-sensitive materials can serve as a universal design principle for next-generation ionic devices.