Among the lead-free compositions identified as potential capacitor materials, BiScO_(3)-BaTiO_(3) (BS-BT)relaxor dielectrics exhibit good energy storage performance. In this research, 0.4BS-0.6BT is consideredas the p...Among the lead-free compositions identified as potential capacitor materials, BiScO_(3)-BaTiO_(3) (BS-BT)relaxor dielectrics exhibit good energy storage performance. In this research, 0.4BS-0.6BT is consideredas the parent composition, with NaNbO_(3) (NN) addition intended to substitute the A and B site cations.The NN modified BS-BT ceramics exhibit excellent temperature stability in terms of their dielectricproperties, with the room-temperature dielectric constant on the order of 500e1 000 and variation lessthan 10% up to 400 C. In addition, NN has a high band-gap energy leading to increased breakdownstrength and energy storage properties in modified compositions. The highest breakdown strength wasachieved for 0.4BS-0.55BT-0.05NN, being on the order of 430 kV/cm, and a high energy density of 4.6 J/cm3 with high energy efficiency of 90% was simultaneously achieved. Of particular importance is that thevariation of the energy density was below 5% due to the temperature-insensitive dielectric constant,while ~90% energy efficiency was retained over the temperature range of 25e160 C. The improvedtemperature stability with NN addition makes this composition promising for high temperaturecapacitor and dielectric energy storage applications.展开更多
文摘Among the lead-free compositions identified as potential capacitor materials, BiScO_(3)-BaTiO_(3) (BS-BT)relaxor dielectrics exhibit good energy storage performance. In this research, 0.4BS-0.6BT is consideredas the parent composition, with NaNbO_(3) (NN) addition intended to substitute the A and B site cations.The NN modified BS-BT ceramics exhibit excellent temperature stability in terms of their dielectricproperties, with the room-temperature dielectric constant on the order of 500e1 000 and variation lessthan 10% up to 400 C. In addition, NN has a high band-gap energy leading to increased breakdownstrength and energy storage properties in modified compositions. The highest breakdown strength wasachieved for 0.4BS-0.55BT-0.05NN, being on the order of 430 kV/cm, and a high energy density of 4.6 J/cm3 with high energy efficiency of 90% was simultaneously achieved. Of particular importance is that thevariation of the energy density was below 5% due to the temperature-insensitive dielectric constant,while ~90% energy efficiency was retained over the temperature range of 25e160 C. The improvedtemperature stability with NN addition makes this composition promising for high temperaturecapacitor and dielectric energy storage applications.