Crystal structure, chemical bond characteristics, infrared reflection spectrum, and microwave dielectric properties of Nd 2(Zr 1− x Ti x ) 3(MoO 4) 9 ceramics

Microwave dielectric ceramics (MWDCs) with low dielectric constant and low dielectric loss are desired in contemporary society, where the communication frequency is developing to high frequency (sub-6G).Herein, Nd 2 (Zr 1-x Ti x ) 3 (MoO 4 ) 9 (NZ 1-x T x M, x = 0.02-0.10)ceramics were prepared through a solid-phase process.According to X-ray diffraction (XRD) patterns, the ceramics could form a pure crystal structure with the R3 ¯c (167) space group.The internal parameters affecting the properties of the ceramics were calculated and analyzed by employing Clausius-Mossotti relationship, Shannon's rule, and Phillips-van Vechten-Levine (P-V-L) theory.Furthermore, theoretical dielectric loss of the ceramics was measured and analyzed by a Fourier transform infrared (IR) radiation spectrometer.Notably, when x = 0.08 and sintered at 700 ℃, optimal microwave dielectric properties of the ceramics were obtained, including a dielectric constant (ε r ) = 10.94,Q•f = 82,525 GHz (at 9.62 GHz), and near-zero resonant frequency temperature coefficient (τ f ) = -12.99ppm/℃.This study not only obtained an MWDC with excellent properties but also deeply analyzed the effects of Ti 4+ on the microwave dielectric properties and chemical bond characteristics of Nd 2 Zr 3 (MoO 4 ) 9 (NZM), which laid a solid foundation for the development of rare-earth molybdate MWDC system.