SPS-Prepared High-Entropy (Bi0.2Na0.2Sr0.2Ba0.2Ca0.2)TiO3 Lead-Free Relaxor-Ferroelectric Ceramics with High Energy Storage Density
Ya Lu, Haibo Zhang, Huabin Yang, Pengyuan Fan, Chanatip Samart, Naohisa Takesue, Hua Tan
Abstract
Compared to batteries and electrochemical capacitors, dielectric capacitors are widely studied because of their huge advantages in terms of charging/discharging speed and power density. In this work, high-entropy (Bi0.2Na0.2Sr0.2Ba0.2Ca0.2)TiO3 lead-free relaxor-ferroelectric ceramics were prepared by both conventional sintering (CS) and spark plasma sintering (SPS). The results showed that the ceramic prepared by SPS obtained a high energy storage density of 6.66 J/cm3 and a satisfied energy storage efficiency of 77.2% under an electric field of 430 kV/cm. This is directly related to the high density, fine grains, number of oxygen vacancies, and composition uniformity of the SPS samples. This study provides a new path for the preparation of high-entropy dielectric energy storage ceramics with high energy storage properties.