Low-Sintering-Temperature Na0.48La0.52-xNdxMoO4 Ceramics with Enhanced Q×f Value: Preparation and Structure-Property Correlation via P-V-L TheoryLn₂Zr3(MoO4)9 Ceramics

Based on the Na _0.48 La _0.52 MoO ₄ ceramic, this study replaced La ³⁺ ions with Nd ³⁺ ions through ion substitution, which significantly increased the Q×f of Na _0.48 La _0.52 MoO ₄ and reduced the sintering temperature. The good sintering state of this series of ceramics was demonstrated by scanning electron microscopy (SEM) and density tests. X-ray diffraction (XRD) and Raman spectroscopy results revealed the formation of solid solutions without the presence of secondary phases or impurities, confirming the synthesis of single-phase molybdate series ceramics. The P-V-L theory indicated that the Na/La/Nd-O bond-to-bond ionicity (fi) contribution was dominant, while the Mo-O bond also played a significant role in the lattice energy (U), bond energy (E), and thermal expansion coefficient (α). Among them, the Na _0.48 La _0.48 Nd _0.04 MoO ₄ ceramic achieved the best dielectric performance at 900℃, with ɛr=11.027±0.018, Q×f=113,805±6,358GHz and τf =-23.36ppm/℃. Through ion substitution, these materials all have low sintering temperatures and high Q×f values, making them ideal candidates for low-temperature co-fired ceramics (LTCC).