Impact of aluminum incorporation on thin-structured iron oxide nanoparticles: A comprehensive study

Abstract

Our research attempts to investigate how doping affects the characteristics of thin iron oxide
(Fe2O3) layers doped with various concentrations of aluminum (Al). The structure, morphology,
and optical characteristics of the films were examined and evaluated in function to the Al doping
level; “1%, 3%, 5%, and 7%, respectively”. As indicated by several characterizations, Fe2O3
formation was confirmed as rhombohedral crystal system by X-ray diffraction, showing strong
preferential orientation in one plane (104). Every peak observed in the un doped samples shows a
continuous, slight shift towards lower values of < 2θ > with increasing aluminum “Al” doping
levels. According to “AFM” data, as the doping ratio increases, the “grain size”, “roughness
rate”, and “root mean square” all increase. The UV spectrum was analyzed to detect the optical
properties. Al-doped Fe2O3 thin films exhibited lower optical absorption than pure film. On the
other hand, the bandgap decreased in the range of (2.31−2.2) eV with increasing Al content. As
well as an increase in aluminum concentration is accompanied by increases in the “coefficient of
absorption and extinction, refraction index”.