Microwave dielectric properties of glass free low temperature co-fired LixNa1-xY(MoO4)2(x=0-0.4) ceramics with temperature stability

作者：Liu, Kaiyang; Gao, Pengxiang; Chen, Xiuli; Zhou, Huanfu^*

来源：Journal of Alloys and Compounds, 2023, 947: 169518.

DOI：10.1016/j.jallcom.2023.169518

• LixNa1-xY(MoO4)2
• Scheelite structure
• Solid solution ceramics
• Microwave dielectric properties
• LTCC materials
• PVL theory

This study set out to the microwave dielectric properties of novel low temperature co-fired LixNa1-xY (MoO4)2(x = 0-0.4) ceramics and adjusted their temperature stability by doping Li+. The XRD confirmed that the doping in the range of x = 0-0.4 would not cause the emergence of the second phase, and the doped Li+ completely entered the lattice and formed LixNa1-xY(MoO4)2 solid solution ceramics, which had tetragonal scheelite structure. The er and Tf of LixNa1-xY(MoO4)2 ceramics move in a positive direction with the increase of doping amount, while the downward trend is observed in Q x f. On the one hand, the change of er and Q x f at different sintering temperatures strongly depends on extrinsic factors such as density, grain size, and holes. On the other hand, this change is closely related to the ionicity, lattice energy, and packing fraction at different compositions. Besides, the change of Tf can be attributed to the influence of bond valence. When x = 0, NaY(MoO4)2 ceramics have the highest Q x f, and when x = 0.25, Li0.25Na0.75Y(MoO4)2 ceramics have the best temperature stability. Their properties are er= 10.69, Q x f= 53080.73 GHz, and Tf= -46.84 ppm/degrees C and er= 12.18, Q x f= 30373.95 GHz, and Tf= -6.35 ppm/degrees C, respectively. Normally, there is good compatibility between Li0.25Na0.75Y(MoO4)2 ceramics and Ag powders.

• 单位
  桂林理工大学