Enhancing structural, optical, magnetic, dielectric and impedance properties of Ba0.95Sr0.05Ca5Ti2-xFexNb8O30 tungsten bronze ferroelectric ceramic through Fe/Ti ratio on optimization for the advanced device applications

Ba0.95Sr0.05Ca5Ti2-xMxNb8O30 (where M = Fe and x = 0.05, 0.15, 0.25, 0.35, 0.45) were synthesized by solid state reaction technique. The effect of the Fe/Ti ratio on structural, dielectric, optical and impedance properties were investigated by altering the value of x. Studies using X-ray diffraction along with Rietveld refinement, Raman and Fourier-transform infrared spectroscopy show that Ba0.95Sr0.05Ca5Ti2-xMxNb8O30 has an orthorhombic columbite structure which is pure phase and having space group Pbcn. The average particle size of the samples by SEM lies in the range of 1-5 mu m. The investigation of the ferromagnetic property at room temperature by vibrating sample measurement technique reveals a modest reduction with doping. At room temperature, a well-sintered pellet's dielectric constant and loss factor were found to be in between 1895.36-9018.16 and 0.45-1.94 respectively. The complex impedance spectroscopy was examined by real and imaginary part of impedance and Nyquist plots to know the electrical properties of the samples. The modulus formalism has also been analyzed to know the accurate relation between the microstructural and electrical properties of the prepared compound. Photoluminescence studies revealed that the prepared samples can be employed as an appropriate photoluminar material.