Dielectric properties and energy storage behaviors in ZnNb_2O_6-doped Sr_(0.97)Nd_(0.02)TiO_3 ceramics

摘要

Using the solid-state ceramic route, Sr_(0.97)Nd_(0.02)TiO_3 ceramics with addition of ZnNb_2O_6 were prepared, and the phase purity, microstructure, dielectric property and energy-storage performance were investigated. The XRD results suggest the formation of solid solutions for all the studied compositions. The SEM results show the moderate addition of ZnNb_2O_6 improves the sintering densification and microstructure of the ceramic samples. The breakdown strength (BDS) is notably improved due to the reduction of the grain size and dense uniform microstructure. And the highest BDS of 493 kV/ cm can be achieved for the sample with 6 wt% ZnNb_2O_6 additive. The Sr_(0.97)Nd_(0.02)TiO_3 ceramic with 6.0 wt% ZnNb_2O_6 addition shows the maximum theoretical energy-storage density of 2.37 J/cm~3, which is 3.4 times higher than that of pure SrTiO_3 in the literature. Therefore, the ZnNb_2O_6 doped Sr_(0.97)Nd_(0.02)TiO_3 ceramics might be a kind of promising energy storage dielectric material.