Control of the shape and size of iron oxide (α-Fe2O3) nanoparticles synthesized through the chemical precipitation method

• Published in: Results in physics Vol. 7; pp. 3007 - 3015
• Main Authors: Lassoued, Abdelmajid, Dkhil, Brahim, Gadri, Abdellatif, Ammar, Salah
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2017; Elsevier
• Subjects: Band gap; Chemical Sciences; Hematite (α-Fe2O3); Inorganic chemistry; Material chemistry; Nanoparticles; Precipitation; Precursor; Size; Nanoparticles; Precipitation; Band gap; Precursor; Size; Hematite (α-Fe2O3)
• ISSN: 2211-3797; 2211-3797
• DOI: 10.1016/j.rinp.2017.07.066

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•α-Fe2O3 nanoparticles were synthesized through chemical precipitation method.•Crystallite size was identified through XRD analysis.•TEM and SEM were used to specify the morphological and size of nanoparticles.•Functional changes of nanoparticles were explored through FT-IR study.•Direct band gap energies were calculated from UV-DRS.
Hematite (α-Fe2O3) nanoparticles were synthesized via a simple chemical precipitation method. The impact of varying the concentration of precursor on the crystalline phase, size and morphology of α-Fe2O3 products was explored. The characteristic of the synthesized hematite nanoparticles were evaluated by X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Fourier Transform Infra-Red (FT-IR) spectroscopy, Raman spectroscopy, Differential Thermal Analysis (DTA), Thermo Gravimetric Analysis (TGA), Ultraviolet–Visible (UV–Vis) analysis and Photoluminescence (PL). XRD data revealed a rhombohedral (hexagonal) structure with the space group R-3c in all samples. Uniform spherical like morphology was confirmed by TEM and SEM. The result revealed that the particle sizes were varied between 21 and 82nm and that the increase in precursor concentration (FeCl3, 6H2O) is accompanied by an increase in the particle size of 21nm for pure α-Fe2O3 synthesized with [Fe3+]=0.05M at 82nm for pure α-Fe2O3 synthesized with [Fe3+]=0.4M. FT-IR confirms the phase purity of the nanoparticles synthesized. The Raman spectroscopy was used not only to prove that we have synthesized pure hematite but also to identify their phonon modes. The thermal behavior of compound was studied by using TGA/DTA results: The TGA showed three mass losses, whereas DTA resulted in three endothermic peaks. Besides, the optical investigation revealed that samples have an optical gap of about 2.1eV and that this value varies as a function of the precursor concentration.