Influence of Ti4+ substitution for Zr4+ on the structure and microwave dielectric properties of Pr2Zr3(MoO4)9 ceramic

Ceramics with composition of Pr ₂(Zr _1−xTi _x) ₃(MoO ₄) ₉ (0.02 ≤ x ≤ 0.10) were fabricated by classic solid-phase method. X-ray diffractometer (XRD), Scanning electron microscope (SEM), Raman spectra, FT-IR spectrometer and Agilent vector network analyzer were used to investigate the composition of phase, microscopy, lattice vibration, internal dielectric responding and dielectric properties, respectively. XRD indicates the Pr ₂(Zr _1−xTi _x) ₃(MoO ₄) ₉ (0.02 ≤ x ≤ 0.10) ceramics own trigonal-type crystal structure and R-3c space group and the SEM patterns confirms the optimal sintering temperature is 800 °C. Simultaneously, the ceramic reached the optimal microwave dielectric properties with ε _r = 10.8, Q×f = 81,539 GHz and τ _f = −14.2 ppm/°C at 800 °C for x = 0.10. By means of the theory of complex crystals chemical bonds (P-V-L theory), the connections with crystal structure and microwave dielectric properties were deeply discussed. Due to the relatively low fired temperature and superior dielectric properties, there is an expect for Pr ₂(Zr _0.90Ti _0.10) ₃(MoO ₄) ₉ ceramic to apply in low temperature cofired ceramic (LTCC).