Scale-up of antiferroelectric TiO₂/ZrO₂/TiO₂ stack with ultra-high energy storage density for supercapacitor application

Yu-Tung Yin^1*, Sheng-Han Yi¹, Hsin-Chih Lin,¹, Miin-Jang Chen¹

¹Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan

* Presenter:Yu-Tung Yin, email:d9806110@gmail.com

In this studying, an antiferroelectric (AFE) TiO₂/ZrO₂/TiO₂ multi-stack structure has been proposed. Through the interdiffusion between TiO₂/ZrO₂ interface, a compressive chemical pressure has arisen and leads to a reduction of hysteresis, which results in a high ESD and low energy loss. A record-high energy storage density (ESD) of 94 J cm^-3 and high efficiency of 80% along with a high maximum power density up to 5x10¹⁰ W kg^-1 has been demonstrated by a single-stacked TiO₂/ZrO₂/TiO₂ AFE capacitor. Furthermore, the TiO₂/ZrO₂/TiO₂ multi-stacked structure also alleviates the decline of energy storage performance with the increase of the film thickness. A high ESD of 80 J cm^-3 and efficiency of 82% has been demonstrated on the TiO₂/ZrO₂/TiO₂ structure with thickness scaled up to 48 nm, and the improvement can be attributed to the superior breakdown strength from the barrier effect of interfaces on electrical trees. Furthermore, the capacitors also exhibit an excellent endurance up to 10¹⁰ operation cycles. With the combination of excellent endurance up to 10¹⁰ operation cycles, high ESD, high efficiency, high power density, and scalability, the TiO₂/ZrO₂/TiO₂ multi-stacked structures demonstrated a promising prospect on supercapacitor applications.

Keywords: antiferroelectric, thin film, ZrO₂, energy storage, supercapacitor