Effect of Sol-Gel Synthesis on the Structural and Photoluminescence Properties of Magnetoplumbite-Type Strontium Ferrite

Magnetoplumbite-type (M-type) strontium ferrite particles with two stoichiometric ratios (SrFexO19; x = 9.2 and 11.6) have been synthesized via the sol-gel technique employing ethylene glycol as the gel precursor. The prepared samples were characterized using x-ray diffractometry (XRD), thermogravimetric analysis (TGA), photoluminescence (PL) spectrophotometry, field emission scanning electron microscopy (FESEM), energy dispersive x-ray spectrometry (EDS) and superconductivity quantum interference device magnetometry (SQUID). X-ray powder diffraction patterns showed that the samples were single-phase with the space group of P63/mmc and cell parameter values of a = 5.88 Ǻ and c = 23.03 – 23.04 Ǻ. EDS results confirmed the composition being mainly of M-type SrFe12O19. The photoluminescence property of strontium ferrite was examined at excitation wavelength of 260 - 290 nm and significant PL emission peaks centered at 334 nm were detected. Both as-prepared strontium ferrites exhibited significant oxygen vacancies which were detectable via TGA where the sample with the Sr/Fe ratio of 1:11.6 exhibited the highest oxygen vacancies in its structure.