Antiferroelectric Fluorite for High Energy Storage Applications
Résumé
Over the past fifteen years, fluorite-structured ferroelectric and antiferroelectric ultrathin films have gained interest for high-density applications. Antiferroelectric ZrO2 shows promise for nanosupercapacitors due to its potential for high energy storage density (ESD) and efficiency (η). This study investigates high-performance Hf1-xZrxO₂ thin films with TiN electrodes exhibiting linear dielectric (LD), ferroelectric (FE), and antiferroelectric (AFE) behavior. AFE ZrO₂ stands out, offering the best trade-off between energy storage density (ESD) and efficiency (η). At 3.5 MV/cm, it achieves 52 J/cm³ with 75% efficiency, reaching 84 J/cm³ at 4.0 MV/cm. Optimization in temperature and thickness leads to a record ESD of 125 J/cm³ for a 10.3 nm-thick ZrO2 thin film. While efficiency and endurance require further improvement, these results confirm AFE ZrO₂ as a promising candidate for high-performance supercapacitors.