Dielectric properties of Ba0.5Sr0.5TiO3–MgO composites synthesized by a citrate gel in situ process

Ba0.5Sr0.5TiO3–MgO (BST–MgO) composite has been prepared in situ by a citrate gel process, which is characterized by differential thermal analysis, X-ray diffraction, scanning electron microscopy, infrared and dielectric spectroscopy. Results show that BST–MgO composite powders can be derived by pH=7 precursor calcined at 700 °C. The BST–MgO composite sintered at 1300 °C exhibits good dielectric properties, with permittivity of 730, loss tangent of 0.002 and tunability of 20.8%.