Crystal structures, bond characteristics, and dielectric properties of novel middle-εr Ln3NbO7 (Ln = Nd, Sm) microwave dielectric ceramics with opposite temperature coefficients

Novel microwave dielectric ceramics based on CaO–MoO3–La2O3 pseudo‐ternary phase diagram and the design of patch antenna

“…Additionally, based on Figure 6C, D, it can be observed that both ceramics contain a certain level of porosity. Therefore, employing Equations ( 10) and (11), this study further calculated the gas pore-corrected dielectric constant (ε corr. ) of the two ceramics .…”

“…Therefore, analyzing the chemical bonds within ceramic crystals allows us to investigate the intrinsic roots that influence their microwave dielectric properties. This paper employs the Phillips–van Vechten–Levine (P–V–L) theory to characterize the various chemical bonds within CaLa 2 (MoO 4 ) 4 and Ca 3 MoO 6 MWDCs to analyze the microwave dielectric properties of the two ceramics at a deep level 11,12 …”

“…This paper employs the Phillips-van Vechten-Levine (P-V-L) theory to characterize the various chemical bonds within CaLa 2 (MoO 4 ) 4 and Ca 3 MoO 6 MWDCs to analyze the microwave dielectric properties of the two ceramics at a deep level. 11,12 Furthermore, the ternary phase diagram is a powerful tool for developing new MWDC systems .13 [17][18][19] The ternary phase diagram provides valuable information about the composition and properties of different ceramic materials, guiding the synthesis and optimization of new and advanced ceramic systems with excellent microwave dielectric properties, reducing the time and raw materials needed in the research process .20 Many molybdate MWDCs are expected to be used in Low Temperature Co-fired Ceramic (LTCC) technology due to their low sintering temperature .21 illustrates the CaO-MoO 3 -La 2 O 3 pseudo-ternary phase diagram. It can be observed from the diagram that research on MWDCs primarily focuses on the MoO 3 -La 2 O 3 binary system, with less emphasis on the Ca-rich MWDCs system.…”

Re2TiO5: Special dielectric titanates exhibiting abnormally low permittivity and a positive coefficient of resonance frequency

“…[1][2][3] At present, the miniaturization and integration of microwave devices, and the development of advanced wireless communication technology represented by 5G have put forward higher and updated requirements for the performance of microwave dielectric ceramics. [4][5][6] A great variety of microwave dielectric ceramics with excellent properties have been reported in recent years, such as Pr 2 (Zr 1−x Ti x ) 3 (MoO 4 ) 9 , Ce 2 [Zr 1−x (Mg 1/3 Sb 2/3 ) x ] 3 (MoO 4 ) 9 , Nd 2 (Zr 1−x Ti x ) 3 (MoO 4 ) 9 , and Ag 2 CaV 4 O 12 . [7][8][9][10] All these ceramics have excellent dielectric properties and low permittivity (ε r < 12).…”

“…Microwave dielectric ceramics, as signal carriers in microwave frequency circuits, generally have a high relative permittivity ( ε r , 10–100), low dielectric loss (tan δ or 1/ Q ), and close‐to‐zero temperature coefficient of resonant frequency ( τ f ), making them applicable in microwave resonators, filters, oscillators, phase shifters, microwave capacitors, and microwave substrate, and so forth 1–3 . At present, the miniaturization and integration of microwave devices, and the development of advanced wireless communication technology represented by 5G have put forward higher and updated requirements for the performance of microwave dielectric ceramics 4–6 . A great variety of microwave dielectric ceramics with excellent properties have been reported in recent years, such as Pr 2 (Zr 1− x Ti x ) 3 (MoO 4 ) 9 , Ce 2 [Zr 1− x (Mg 1/3 Sb 2/3 ) x ] 3 (MoO 4 ) 9 , Nd 2 (Zr 1− x Ti x ) 3 (MoO 4 ) 9 , and Ag 2 CaV 4 O 12 7–10 .…”