Ternary nanocomposite of ZnFe₂O₄/α-Fe₂O₃/ZnO; synthesis via coprecipitation method and physical properties characterization

Abstract

ZnFe₂O₄/α-Fe₂O₃/ZnO, the ternary transition metal oxide nanocomposite powder was successfully synthesized by facile coprecipitation method directly from metalorganic precursors within 4 h of processing time considerably shorter than other reported methods. To study the post-synthesis thermal treatment effects on physical properties, calcination process was applied at 500, 600, and 700 °C individually for one hour. The structure, phase formation, morphology, and optical features of the samples were characterized by employing powder X-ray diffraction, scanning electron microscopy, and UV–visible spectroscopy. The results confirm the synthesis of pure and homogeneous composites comprised of nanoparticles with good crystallization in a narrow range of crystallite sizes between 25–39 nm. The particle sizes also were estimated between 48–93 nm. The optical property was studied by recording the absorbance spectrum from 200 to 700 nm. The absorption pattern illustrates the nanocomposite can be driven by UV and visible wavelengths with good efficiency that is more desirable for intended applications like photocatalytic activities compare with the individual components. By applying Tauc's method, the allowed direct bandgap and indirect bandgap of the prepared nanocomposite were estimated to be around 2.28 and 2.75 eV, respectively.