Dielectric properties of Ti4+/Zr4+ modified the SrCeO3-based microwave ceramic systems

A series of new systems of the SrCe 1- x Ti x O 3 and SrCe 1− x Zr x O 3 (SCT x and SCZ x , x  = 0.0–0.1) ceramics have been prepared by the traditional solid-phase methods. The XRD patterns results show that an ABO 3 -type perovskite structure of the SrCeO 3 ceramic can be obtained as x  = 0.0. With the increase in Ti 4+ - and Zr 4+ -ions-doping content of x  = 0.02–0.1, the SCT x and SCZ x ceramics basically belong to the perovskite phase with the orthorhombic structure of the space group Pmcn (62), and the results of EDS analysis on the proportion of each element can also verify the correctness of the XRD analytical results. In addition, all the microstructures are dense for the SCT x and SCZ x ( x  = 0.0–0.1) samples. The fitting results of complex plane impedance verified that the temperature stability of SCT x solid solution ceramics is more suitable for adjusting to the practical application range. Especially, the SCT x ( x  = 0.03) ceramics sintered at 1270 °C for 4 h can obtain the relatively excellent dielectric properties of ε r  = 50.16, Q  ×  f  = 8,940 GHz (at 5.91 GHz), and τ f   =  + 0.08 ppm/°C.