Low sintering temperature Na0.48La0.48Nd0.04MoO4 ceramics: high Q × f value characteristics and structure–performance correlation based on P–V–L theory

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. 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 °C, with ɛ r  = 11.027 ± 0.018, Q  ×  f  = 113,805 ± 6,358 GHz, and τ f  = − 23.36 ppm/℃. 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).