Data on study of hematite nanoparticles obtained from Iron(III) oxide by the Pechini method

This article presents the data on α-Fe2O3 nanoparticles synthesized via Pechini method using iron(III) oxide precursor from steel industry. It is important to highlight the added value that is given to an industrial waste. The samples were characterized by thermal analysis (DTA, TG), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The TG showed three mass changes, whereas DTA resulted in three anomalies. X-ray diffraction pattern of the samples disclosed rhombohedral structure characteristic of the nanocrystalline α-Fe2O3 phase. The crystallite size was estimated for each thermal treatment. Fourier transform infrared spectroscopy confirms the phase purity of prepared nanoparticles. A detailed study on the local structure of the samples was carry out in the region of 800 and 400 cm−1, where the associated bands of Fe–O bonds are presents. The data have not been reported nor discussed for now.


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This article presents the data on a-Fe 2 O 3 nanoparticles synthesized via Pechini method using iron(III) oxide precursor from steel industry. It is important to highlight the added value that is given to an industrial waste. The samples were characterized by thermal analysis (DTA, TG), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The TG showed three mass changes, whereas DTA resulted in three anomalies. X-ray diffraction pattern of the samples disclosed rhombohedral structure characteristic of the nanocrystalline a-Fe 2 O 3 phase. The crystallite size was estimated for each thermal treatment. Fourier transform infrared spectroscopy confirms the phase purity of prepared nanoparticles. A detailed study on the local structure of the samples was carry out in the region of 800 and 400 cm À1 , where the associated bands of FeeO bonds are presents. The data have not been reported nor discussed for now.

Data
The data contain a description on synthesis of hematite nanoparticles via Pechini method. The synthesis procedure is shown in flowchart (Fig. 1). The precursor material was obtained from steel industry, an industrial waste. Their characterization was carried out using various analytical techniques (TG, DTA, XRD, and FTIR). Thermal analysis methods (TG/DTA) were used to study the endothermic processes (vaporization, phases transitions and chemical degradation) as well as exothermic processes (crystallization and oxidative decomposition), see Fig. 2. Additionally, structural characterization was carried out by XRD ( Fig. 3 and Table 1). FTIR spectra of the samples are presented in Fig. 4. A more detailed analysis was carried out using a deconvolution of the FTIR spectra to bands at lower wavenumber than 800 cm À1 (Fig. 5). All corresponding Table and figures are provided with this article.
This article reports the detailed data analysis from a-Fe 2 O 3 nanoparticles.

Synthesis and characterization of a-Fe 2 O 3 nanoparticles
An oxide ferric precursor from steel industry (industrial waste) was used to synthesize hematite (a-Fe 2 O 3 ) nanoparticles. The reagents were obtained from Mallinckrodt Pharmaceuticals (Ethylene glycol, P.A. 99.8%) and Merck (Citric acid, P.A. 99.5%; Ammonium hydroxide, P.A. 99%) and used as received. For characterization of the samples, the thermal analysis (TG/DTA) was performed using TA Instruments under N 2 atmosphere, X-ray diffraction (XRD) were obtained using a PANalytical X'Pert Pro diffractometer, and an infrared spectrophotometer (Nicolet 6700 FTIR, Thermo Scientific) was used to obtain the IR spectra of the samples.   [7].

Value of the data
Method and data will be advantageous for scale up iron oxide nanoparticles from oxide ferric obtained of the steel industry. It is important to highlight the added value that is given to an industrial waste. The data provide structural information about hematite nanoparticles synthetized via Pechini method. The full data and data analysis shown in this data in brief article can be used for quantitative comparison with data from other studies of similar materials exposed to different experimental conditions.  the precursor material in an acidic media under a basic pH under stirring at 140 C. In this procedure, the yield was around 40% for each sample.

Dataset description
Thermal analysis was carry out from room temperature (RT) to 1200 C with finality to determine the formation and decomposition phase occurring during heat treatment of synthesized samples. Fig. 2 displays the thermal analysis (TG and DTA) for the pre-calcined samples. In TG thermogram, three mass changes were observed and associated with the three anomalies showed in DTA thermogram. For TG, a first weight loss step occurred gradually between room temperature and 208 C. The mass loss was of4 .1%, which is attributed to the elimination of water present on a-Fe 2 O 3 nanoparticles. Additionally, the DTA analysis enabled us to find an endothermic peak at 65 C confirming the water elimination. A second step corresponds to a mass loss of~22.18% occurring at around 208e400 C, exothermic peak at 368 C for DTA curve, which is associated to the volatile compounds, oxidation of the organic phase present in the samples and crystallization of the oxide. In addition, in DTA curve is observed a third peak at around 820 C, which is associated with a little mass gain giving rise to an oxidation that is possibly associated to the loss of magnetism [1]. Based on the TG/DTA analysis, for the ceramic powders obtained by the Pechini method, it was defined that the most suitable temperature for the calcination of the material should be higher than 450 C.
By treating the sample thermally at 500 C, a greater crystallization is achieved. The XRD pattern match well with the PDF no. 75e469 of the rhombohedral structure of pure hematite (a-Fe 2 O 3 ) [1,4e6], as indicated by the DTA analysis (Fig. 2). This phase is stable over a wide range of temperatures (300e1200 C), but their magnetic property decreased with increasing of temperature (no shown). The crystallite average size was determined using the Debey-Scherrer formula [1,4,6,7], and reported in Table 1. Fig. 4 shows the FTIR spectra for a-Fe 2 O 3 samples synthesized by the Pechini method at different temperatures. For the precalcined sample, the typical OeH bands at~3410 cm À1 and~1606 cm À1 , indicate that during the resin formation, all water present in the sample was not completely eliminated, and is in agreement with thermal studies. These bands appear strongly in the spectrum at 300 C, but their % transmission decreases as the temperature increases. In addition, this shows that the presence of the OH groups in the samples decreases as the temperature increases, disappearing in the sample treated at 500 C. The wide band around 1370 cm À1 can be associated with the vibrational band of residual CeH groups [8].