Correlation between crystal structure and dielectric characteristics of Ti4+ substituted CaSnSiO5 ceramics

The crystal structure and dielectric properties of Ti4+-substituted CaSnSiO5 ceramic were investigated. Ti4+ entirely substituted Sn4+ of CaSnSiO5, and the solid solutions were formed at Ca(Sn1-xTix)SiO5 (0 < x < 1.0) ceramics. The evolutions of crystal structure were analysed through Rietveld refinement and transmission electron microscopy, and the phase transition from A2/a to P2(1)/a space groups at Ca(Sn1-xTix)SiO5 (0.9 <= x <= 1.0) ceramics was clarified. The change in dielectric properties was related to the structural evolution of Ca (Sn1-xTix)SiO5 (0 <= x <= 1.0). The of values of Ca(Sn1-xTix)SiO5 (0 <= x <= 0.4) ceramics initially decreased to +49.8 ppm/degrees C and then increased to +98.3 ppm/degrees C because of Sn/TiO6 octahedral distortion. The temperature coefficient of capacitance and epsilon(r) anomaly peak were controlled by Ti4+ substitution for Sn4+ at Ca(Sn1-xTix)SiO5 (0.4 <= x <= 1.0) ceramics. The results provided a way to control the of the tau(f) value of microwave dielectric ceramics.

Automated summary

The crystal structure and dielectric properties of Ti4+-substituted CaSnSiO5 ceramic were investigated, where Ti4+ entirely substituted Sn4+ leading to structural evolution and change in dielectric properties. The results provided ways to control the tau(f) value of microwave dielectric ceramics.