Room temperature fabrication and post-impregnation of LMO-ST composites: Engineering and modeling of dielectric properties

In this work, the effect of changing the Li2MoO4-SrTiO3 (LMO-ST) compositional proportion (1-100 wt%) on the microstructure, dielectric properties, and relative density of LMO-ST composites fabricated at room temperature was investigated. The results showed that increasing the LMO binder content resulted in a higher relative density (up to 93%), but a lower dielectric constant in the range of 75 to 5. Good agreement between the experimental results and the predicted values of relative permittivity was obtained using the Lichtenecker model, reformulated for a three-phase composite system. Modeling further explained the detrimental effects of porosity on the dielectric properties. To address this issue, impregnation with titanium (IV) isopropoxide (TTIP) was found to reduce overall porosity and improve relative permittivity from 72 to 99 at 1 MHz. The room temperature fabrication offers a wide range of relative permittivity for LMO-ST composites.