High-entropy engineered BaTiO3-based ceramic capacitors with greatly enhanced high-temperature energy storage performance
Xi Kong, Letao Yang, Fanqi Meng, Tao Zhang, Hejin Zhang, Yuanhua Lin, Houbing Huang, Shujun Zhang, Jinming Guo, Ce‐Wen Nan
Abstract
Ceramic capacitors with ultrahigh power density are crucial in modern electrical applications, especially under high-temperature conditions. However, the relatively low energy density limits their application scope and hinders device miniaturization and integration. In this work, we present a high-entropy BaTiO3-based relaxor ceramic with outstanding energy storage properties, achieving a substantial recoverable energy density of 10.9 J/cm3 and a superior energy efficiency of 93% at applied electric field of 720 kV/cm. Of particular importance is that the studied high-entropy composition exhibits excellent energy storage performance across a wide temperature range of −50 to 260 °C, with variation below 9%, additionally, it demonstrates great cycling reliability at 450 kV/cm and 200 °C up to 106 cycles. Electrical and in-situ structural characterizations revealed that the high-entropy engineered local structures are highly stable under varying temperature and electric fields, leading to superior energy storage performance. This study provides a good paradigm of the efficacy of the high-entropy engineering for developing high-performance dielectric capacitors. The authors utilize a high-entropy design strategy to enhance the high-temperature energy storage capabilities of BaTiO3-based ceramic capacitors, realizing energy storage performance from −50 °C to 260 °C and maintaining functionality after one million charge-discharge cycles at 200 °C.