Structural, Optical, and Electronic Characterization of Fe-Doped Alumina Nanoparticles

The effects of iron doping on the structural, optical, and electronic properties of doped alumina have been studied. Single-phase iron-doped alumina Al2-x Fe (x) O-3 (x = 0.00 to 0.30) nanoparticles were synthesized via citrate-precursor method. Formation of single-phase hexagonal corundum structure with no other separate phases was demonstrated by x-ray diffraction (XRD) analysis and Fourier-transform infrared spectroscopy. The effects of iron doping on the alpha-Al2O3 structural parameters, viz. atomic coordinates, lattice parameters, crystallite size, and microstrain, were estimated from XRD data by applying the Rietveld profile fitting method. Transmission electron microscopy further confirmed the nanosize nature of the prepared samples with size ranging from 12 nm to 83 nm. The electronic band structure was investigated using density functional theory calculations to explain the decrease in the energy gap of Al2-x Fe (x) O-3 as the amount of Fe was increased. The colored emission peaks in the visible region (blue, red, violet) of the electromagnetic spectrum obtained for the Fe-doped alpha-Al2O3 nanoparticles suggest their potential application as ceramic nanopigments.