Effects of Strontium on the Structural, Optical, and Microwave Dielectric Properties of Ba(2)Ti(9)O(20) Ceramics Synthesized by a Mixed Oxide Route

[Image: see text] Solid solutions of Sr-doped barium nonatitanate (Ba(2)Ti(9)O(20)) ceramics were synthesized by a mixed oxide route, studied their structural, microstructural, optical, and microwave dielectric properties were studied. X-ray diffraction (XRD) has been used to reveal the structure and crystallite size of doped Ba(2)Ti(9)O(20) ceramics. Rietveld refinements of XRD patterns revealed that all of the ceramics have a tetragonal structure with space group I4/m. The surface morphologies of all the samples were characterized by using scanning electron microscopy (SEM). Fourier transform infrared (FT-IR) studies gave the O–H and Ti–O modes of vibrations. The stretching modes of Ti–O and O–H were noted at 1400, 2960, 3700, and near to 440 cm(–1), respectively. The band gap energy decreases with increasing Sr(2+) contents, and a high value (2.12 eV) was observed in the base sample. The microwave dielectric properties of the ceramic samples were studied at different frequencies ranging from 1 to 2 GHz by using impedance spectroscopy. The obtained results showed the suitability of these samples for microwave dielectric resonator (antenna) applications.