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

Abstract

Ceramics with composition of Pr 2 (Zr 1−x Ti 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−x Ti 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 0.90 Ti 0.10 ) 3 (MoO 4 ) 9 ceramic to apply in low temperature cofired ceramic (LTCC). • Rietveld refinement was used to obtain the cell parameters. • The effects of substitution of Zr 4+ by Ti 4+ on Pr 2 Zr 3 (MoO 4 ) 9 ceramics was explored based on the P-V-L theory. • Q·f value has been improved by more than 130% in Pr 2 (Zr 0.90 Ti 0.10 ) 3 (MoO 4 ) 9 ceramics. • Optimum microwave dielectric properties ( ε r = 10.8, Q×f = 81,539 GHz and τ f = −14.2 ppm/°C) were obtained at 800 °C.