Overview of Interface Ionics Project (2019–2024)

Solid–solid interfaces generate entirely new functions different from the intrinsic nature of each solid material. In this project, unique interfacial ion dynamics around the hetero/homo interfaces of solid state ionics materials (SSIM) are systematically investigated so as to establish design principles for fast ion transport and concentrated ion storage around interfaces, that is, “Interface Ionics.” We expected that “Interface Ionics” clarifies design principle of interface in all-solid-state batteries where fast ion transport and concentrated ion storage are expected for high-rate and stable charge–discharge reactions and high capacity electrode materials. Furthermore, those interfaces are effective to develop novel solid state ionics devices such as all-solid-state capacitor, transistor, and electret.