Crystal structure and microwave dielectric properties of Li₂(Mg_1-xCu_x)< sub>2Mo₃O₁₂ ceramics sintered at ultra-low temperature

Li-2(Mg1-xCux)(2)Mo3O12 (0 <= x & <= 0.1) ceramics were prepared using the conventional solid-phase method to study the effect of the Cu2+ substitution for Mg2+ on the sintering behavior, crystal structure, and microwave dielectric properties of ceramics. The experimental results show that the substitution of Cu2+ for Mg2+ reduces the sintering temperature of the ceramics to 550(degrees)C. X-ray diffraction patterns show that the introduction of Cu2+ does not produce a new phase, but rather promotes the formation of Li-2(Mg1-xCux)(2)Mo3O12 solid solution. The microwave dielectric properties of the ceramics are influenced by the cell parameters, bond lengths, and structural stability. However, Cu2+ creates oxygen vacancies during sintering, thereby deteriorating the dielectric properties (Q x f decreases). The microwave dielectric properties of Li-2(Mg1-xCux)(2)Mo3O12 ceramics are optimal at a sintering temperature of 550(degrees)C and x = 0.02, with epsilon(r) = 9.17, Q x f = 7960 GHz, and tau(f) = -58.77 ppm/C-degrees. Additionally, these ceramics are compatible with Al electrodes.