Optical and electronic properties of copper and cobalt substituted nano SrBaFe${}_{12}$O${}_{19}$ synthesized by sol–gel autocombustion method

The current study addresses the synthesis and characterization of Sr${}_{0.5}$Ba${}_{0.5}$Fe${}_{12-2x}$Co${}_x$Cu${}_x$O${}_{19}$ (x = 0.0-0.8) (SBFCCO) nanoparticles prepared via sol-gel autocombustion route. The diffraction pattern revealed the formation of the single phase hexagonal structure. The average crystallite size was noted to be altering from 8 to 12 nm. The TEM pictures also reveal the agglomerated facets like nanoparticles of particle size changing from > 200 to 40 nm for various 'x' values. The dielectric parameters were calculated and elucidated as a function of frequency and temperature. In addition, the UV-visible spectra expressed the significant decrease in bandgap energy from 3.54 to 2.80 eV with increase of doping content. Therefore, these samples may reveal wide applications in optoelectronic devices, photo catalytic and sensor based applications because of the wide band gaps.