Dy2O3 Nanoparticles Research Articles

Critical current density improvement of RHQT Nb3Al superconducting wires by incorporating magnetic Dy2O3 nanoparticles as additional flux pinning centers

In this paper, we prepared magnetic Dy2O3 nanoparticles (n-Dy2O3) doped Nb3Al superconducting wires by rapid heating, quenching and transformation (RHQT) method, and investigated the micro-defects, superconducting properties and flux pinning mechanisms. TEM results showed high-density stacking faults (SF) with spacing of 5–25 nm located in Nb3Al (210) crystal planes, which is due to the absence of Nb atoms on the {100} crystal planes. Additionally, many intra-granular and inter-granular Dy2O3 nanoparticles with size of 4–40 nm were also observed in the Nb3Al superconducting phase. Jc was promoted in the doped samples, obtaining the best Jc of 1.95 × 105 A/cm2@ 4.2 K, 12 T in 1 at.% n-Dy2O3 doped Nb3Al wire, which was nearly 70 % higher than pristine Nb3Al wire. By doping n-Dy2O3, the fP(Fp/Fp,max)-h(B/Birr) peaks shift to larger h value (higher field). The flux pinning mechanism by fitting fP-h curves showed dominant surface pinning combined with point pinning, corresponding to the crystal defect of stacking faults and nanoparticles, respectively. The pinning mechanism verified that the nanoparticles acted as additional pinning centers to significantly elevate the Jc performance.

Biosynthesis of Dy2O3 nanoparticles using Piper Retrofractum Vahl extract: Optical, structural, morphological, and photocatalytic properties

Biosynthesis of nanoparticles has attracted much attention due to its environmental safety, cost-effectiveness, and straightforward fabrication. For the first time, Piper Retrofractum Vahl Fruits Extract (PRFE) was used as a low-cost natural hydrolyzing agent in the synthesis of Dysprosium Oxide (Dy2O3). The optical, structural, morphological, and photocatalytic properties of Dy2O3 nanoparticles were observed by various characterization methods such as FT-IR, XRD, UV-Vis DRS, FESEM-EDS, and TEM. The absorption bands of the C-N and N-H functional groups were revealed by FT-IR analysis. Alkaloid compounds of PRFE are assigned to the hydrolyzing agents. Furthermore, the XRD and EDS analyses confirmed the presence of Dy2O3 without impurities. Morphological characterization by FESEM showed that Dy2O3 nanoparticles were in a spherical shape, while the particles size was obtained to be 20-30 nm validated by TEM measurement. The optical bandgap of Dy2O3 was 4.8 eV, which is active in the UV region. Dy2O3 nanoparticles showed a remarkable photocatalytic activity, which has an efficiency of 92.76%, with a small amount of catalyst loading for malachite green degradation under UV light irradiation within 120 min. The trapping experiment proved that h+ is the predominant reactive species in the photodegradation reaction. Ultimatelly, this work presents a superior biosynthesized Dy2O3 photocatalyst, which demonstrates high stability in four consecutive cycles.

Intergrain connectivity in YBa2Cu3O7-δ superconductor added with Dy2O3 nanoparticles: AC susceptibility investigation

YBa2Cu3O7-δ (or YBCO) superconductors added with various concentrations of dysprosium oxide nanoparticles (NP-Dy2O3) were prepared using the solid-state process. The additive NP-Dy2O3 has a size of about 10 nm and presents a para/ferromagnetic transition at about 300 K. The characterization of samples was probed via XRD, TEM, SEM, DC magnetization, and AC susceptibility measurements. Some models were employed to compute superconducting parameters like intragranular critical current density under a magnetic field (Jcm(H)), the density of intragranular pinning force for Abrikosov vortex (εg(0)), intergranular critical current density (Jc,inter), intergranular electrical character, superconductor grain volume fraction (fs). The correlation between these parameters and microstructure was discussed. The inclusion of NP-Dy2O3 does not alter the structural properties and the spatial growth of YBa2Cu3O7-δ. NP-Dy2O3 addition led to significant enhancements of Jcm(H) and εg(0). The decrement in Jc,inter was attributed to the change of grain boundary characteristics that transformed from SNS to SINS junction due to NP-Dy2O3 addition.

Potential applicability of polyethyleneimine PEI-coated Eu2O3 and Dy2O3 nanoparticles for contrast enhancement in computed tomography

Rare-earth metal oxide nanoparticles considered promising contrast agents for x-ray computed tomography (CT) and magnetic resonance imaging (MRI). The main purpose of this study is to investigate the potential applicability of polyethyleneimine (PEI)-coated Eu2O3 and Dy2O3 nanoparticles (NPs) for CT x-ray attenuation. Morphology and other physicochemical properties of prepared samples were systematically investigated using a range of characterization tools. Preliminary cytotoxicity experiments with L-929 fibroblastic cells suggested that both samples have no significant toxicity at concentrations below 100 μg ml−1. Clinical CT analysis shows that PEI@Eu2O3 NPs exhibit higher x-ray attenuation efficiency (∼8 HU mM−1) as compared to PEI@Dy2O3 NPs (∼5 HU mM−1).

Biosynthesis driven dysprosium oxide nanoparticles as a sensor for picric acid

In the present study, we have used biosynthesized Dy2O3 nanoparticles (Nps) for the selective detection of (Picric acid) PA. A simple and eco-friendly route to develop Dy2O3 nanoparticles (Nps) with the aid of clove bud extract as naturally available fuel was used. Biosynthesized and its counterpart, calcined sample c-Dy2O3 were characterized by UV–visible, FT-IR, XRD, TEM, XPS and TGA analysis. FT-IR results indicated the preliminary evidence of Dy–O bond in the synthesized Nps. XRD pattern confirmed that Dy2O3 has amorphous nature and its counterpart has typical cubic crystal structure. Toxicological profiling of Dy2O3 Nps was performed against bacteria and plants using bioassays. The experiments marked the absence of zone of inhibition against bacteria using Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative) which revealed the non-toxicity of Dy2O3 Nps. Seed germination assay divulged elevated biocompatibility of Dy2O3 Nps towards black gram seeds w.r.t. control at a concentration of Nps even at high concentration of 1000 ​ppm. The synthesized Nps demonstrated excellent sensitivity and selectivity towards picric acid with Limit of detection (LOD) of 43 ​± ​1.5 ​nM. The high value of Stern –Volmer constant (Ksv), 4.19 ​× ​104 ​M signifies the high selectivity of Dy2O3 Nps for PA. We believe that the biosynthesized Dy2O3 Nps will emerge as potential candidate for selective detection of trace amounts of nitro explosives in waste water.

Flux pinning mechanisms of (YBa2Cu3Oy-d)1−x/(Dy2O3)x superconductors (x=0.1 and 0.5 wt%)

Polycrystalline (YBa2Cu3Oy-d)1−x/(Dy2O3)x superconductor samples were produced through the solid-state reaction route and by adding amounts of x = 0.1 and 0.5 wt% of Dy2O3 nanoparticles (NP-Dy2O3 with a size of about 10 nm) during the second stage of heat treatment. The structural, microstructural, critical current density and pinning properties were investigated using x-ray diffraction, scanning electron microscope, and DC magnetization at various temperatures ranging from 77 down to 10 K and under an applied magnetic field varying between −6 and +6 Tesla. Both samples crystallize in the orthorhombic structure. It was found that the Dy2O3 nanoparticles reside in the grain boundaries. Although the sample with 0.5 wt% NP-Dy2O3 is characterized by a low zero resistive temperature of about 78 K that is close to the useful temperature for technological applications, it showed the highest Jc values and the excellent flux pinning capacity. The addition of an appropriate amount of NP-Dy2O3 up to 0.5 wt% extends the single bundle pinning regime and retards the liquid vortex regime.

Enhanced critical current density and flux pinning traits with Dy2O3 nanoparticles added to YBa2Cu3O7-d superconductor

Addition of nanosized material in YBa2Cu3O7–d to produce artificial pinning cores is benefit way to enhance the in-field current-carrying capacity and flux pinning properties. In this work, we report the impact of nano-dysprosium oxide particles (Dy2O3) with a size of ̴ 10 nm on the mechanisms and the strength of pinning centers of polycrystalline YBa2Cu3O7–d. Samples of YBa2Cu3O7–d + x Dy2O3 with x = 0.0 and 0.1 wt% were prepared via solid-state reaction way. X-ray diffraction and scanning electron microscope observations were performed to characterize the structure and the morphology of samples. Measurements of D.C magnetization against applied magnetic field from −6 to +6 T were implemented to estimate the critical current density and verify the pinning mechanisms at different temperatures ranging from 77 down to 10 K. The orthorhombic YBCO structure is preserved in both samples, NP–Dy2O3 weakens the grains linkage, drops the zero resistive temperature Tc by 1.6 K and weakens the inter-granular critical current density. Over the measured temperature range and exterior magnetic fields, results showed higher intra-granular current density and a best ability to trap vortex in the 0.1Dy-YBCO composite. Pinning centers were categorized into weak and strong pinning centers. NP–Dy2O3 gives more weight to the strong pinning components.

Impact of Dy2O3 nanoparticles additions on the properties of porous YBCO ceramics

In this work, we report the effects of dysprosium oxide (Dy2O3) magnetic nanoparticles inclusion on superconducting characteristics and flux pinning of YB2Cu3O7−δ (for brevity YBCO) compound. Using the solid-state reaction route, series of YBa2Cu3O7−δ/(Dy2O3)x were produced by adding up to 0.5 wt% Dy2O3. The crystal structure, morphology, electrical and magnetic properties were examined using X-ray diffraction, scanning electron microscopy, electrical resistivity and physical properties measurement system (PPMS), respectively. The orthorhombicity was preserved with Dy2O3 addition. The electrical resistivity dependence with the temperature (()) revealed the manifestation of superconducting transition in all prepared samples. By increasing x up to 0.2 wt%, an increase of critical current density $$\left( {J_{c} } \right)$$ was achieved. The flux pinning ability and the dominant pinning mechanisms in YBa2Cu3O7−δ/(Dy2O3)x composites were checked and discussed.

Synthesis, characterization, and X-ray attenuation properties of polyacrylic acid-coated ultrasmall heavy metal oxide (Bi2O3, Yb2O3, NaTaO3, Dy2O3, and Gd2O3) nanoparticles as potential CT contrast agents

Ultrasmall heavy metal oxide nanoparticles are potential candidate materials for X-ray computed tomography (CT) contrast agents because they possess high X-ray attenuation powers owing to high X-ray attenuation coefficients of heavy metal atoms and high density of heavy metal atoms per nanoparticle. In this study, five kinds of polyacrylic acid (PAA)-coated ultrasmall heavy metal oxide (Bi2O3, Yb2O3, NaTaO3, Dy2O3, and Gd2O3) nanoparticles were synthesized and their X-ray attenuation properties were investigated. The estimated average particle diameters were 2.3 ± 0.1, 1.7 ± 0.1, 1.5 ± 0.1, 1.8 ± 0.1, and 1.9 ± 0.1 nm for PAA-coated ultrasmall Bi2O3, Yb2O3, NaTaO3, Dy2O3, and Gd2O3 nanoparticles, respectively. All of the nanoparticle suspension samples exhibited a high colloidal stability, a high biocompatibility, and X-ray attenuation powers which were stronger than that of a commercial iodine contrast agent Ultravist® at the same atomic concentration and much stronger, at the same number density. The effectiveness of the nanoparticle suspension samples as CT contrast agents was demonstrated by acquiring in vivo CT images by using one of the samples (i.e., PAA-coated ultrasmall Bi2O3 nanoparticles). After intravenous injection into the mouse tail vein, positive contrast enhancements in various organs were observed.

Electrochemical deposition and plane-wave periodic DFT study on Dy2O3 nanoparticles and pseudocapacitance performance of Dy2O3/conductive polymer nanocomposite film

Abstract In view of the current trend to apply green chemistry to product development and to reduce the use of toxic materials, this work is based on the optimization of a green cathodic electrodeposition method and followed heat treatment to prepare nanostructured Dy2O3, in an aqueous solution of dysprosium (III) nitrate hydrate. Prepared Dy2O3 nanoparticles have been characterized by different analysis such as FT-IR spectroscopy, thermogravimetric-differential scanning calorimetry (TG-DSC), field-emission scanning electron microscopy (FE-SEM) and X-Ray diffraction (XRD). Not only from the XRD spectrum but also using the Nelson–Riley functions, various mechanical parameters referring to Dy2O3 nanoparticles, e.g. particle size, texture coefficient, strain, and lattice constant, were determined. To understand more details about the bulk structure and electronic properties of Dy2O3, periodic plane-wave density functional theory calculations have been conducted by Quantum Espresso code. Dy2O3 exhibits an indirect band gap of 2.0 eV was computed using first-principle density functional theory (DFT) calculations. For improving electrochemical properties of the poly ortho aminophenol (POAP), we fabricated POAP/Dy2O3 films by electro-polymerization of POAP in the presence of electrosynthesized Dy2O3 with porous structure, to serve as the active electrode for electrochemical supercapacitor. In terms of electrochemical methods, galvanostatic charge–discharge experiments, cyclic voltammetry (CV) and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. The enhanced supercapacitor behavior observed for the prepared composite film can be attributed to synergistic effect existing between Dy2O3 nanoparticles and the conductive polymer.

Interfacial Charge Transfer and Effective Termination of Electron Recombination Process in (ZnO)(1-x)/2(Bi2O3) x (Dy2O3)(1-x)/2 Heterostructured Nanocomposite Material under Visible Light Irradiation.

We have synthesized a novel heterostructured composite material-(ZnO)(1–x)/2(Bi2O3)x(Dy2O3)(1–x)/2 wherein electron–hole recombination has been successfully inhibited by an interfacial charge-transfer mechanism across a semiconductor interface. As a result of this, the material possessed enhanced photoresponse under visible light irradiations. X-ray diffraction analysis shows the material to be highly nanocrystalline in nature. The band gap energy as calculated from the UV–vis–diffused reflectance spectroscopy spectrum was found to be 2.68 eV. Morphological studies by high-resolution scanning electron microscopy and high-resolution transmission electron microscopy analyses show the presence of distinct microrod-shaped αBi2O3 and spherical ball-like clusters of ZnO and Dy2O3 nanoparticles. X-ray photoelectron spectroscopy and energy-dispersive X-ray analyses confirm the presence of Bi, Zn, Dy, and O in the material. Atomic force microscopy (AFM) analysis revealed the high surface roughness and porosity of the prepared composite. Electron paramagnetic resonance analysis confirmed the in situ generation of OH•radicals under visible light irradiation. The photocatalytic efficiency of the (ZnO)(1–x)/2(Bi2O3)x(Dy2O3)(1–x)/2 composite material was evaluated by the photooxidation of Orange G (OG) dye molecules under visible light irradiation. The catalyst retained its original efficiency even after the 3rd cycle of its reuse thereby validating the economic feasibility of the system. By-product analysis by ESI-MS+ analysis proved the complete degradation of the OG molecules from the aqueous solution.

Effect of pure and REM: (Nd, Ce)-doped Dy2O3 NPs via hydrothermal method and their magnetic, optical, electrochemical, antibacterial and photocatalytic activities

Pure Dysprosium oxide (Dy2O3) with the spherical-morphology based material, and the rare earth metal (REM) - doped Dy2O3 nanoparticles (NPs) were synthesized using the reaction of dysprosium (III) nitrate pentahydrate, neodymium (III) nitrate hexahydrate and cerium (III) nitrate hexahydrate by the simple cost-effective hydrothermal method, which exhibits high antibacterial effects and photocatalytic activity. The antibacterial effect of pure and (5 mol% of Nd, Ce) - doped Dy2O3 NPs, on Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi were studied by using various concentrations. The photocatalytic activity of pure and 5 mol% of cerium doped Dy2O3 NPs were assessed by degrading the methyl orange (MO) dye under UV irradiation. The characterization results indicated that the XRD and TEM studies confirms the size of the prepared Dy2O3 NPs decreased with Nd and Ce insertion into dysprosium oxide. The particle size calculated from the Williamson-Hall (W-H) plot was consistent with TEM results. From VSM analysis, cerium doped NPs shows high saturation (Ms) magnetization than that of pure Dy2O3 NPs. The emission spectra and electrochemical properties are found to be dopant dependent. 5 mol% of Ce-doped Dy2O3 NPs shows good antibacterial effect compared to that of pure and Nd doped sample. From the above, it is observed that cerium doped NPs exhibit high photocatalytic activity than pure NPs. The mineralization of MO dye solution for pure and 5 mol% of Ce-doped samples has been confirmed by chemical oxygen demand (COD) measurements. In addition, the rate of decolorization is also confirmed by the total organic carbon (TOC) study. From the results, cerium doped sample enhances the photocatalytic performance compared to pure Dy2O3 NPs due to the lower recombination rate of electron-hole pairs and the presence of large surface area of the samples act as reactive facets for adsorption of MO dye molecules.

Absorption and emission analysis of zinc borotellurite glass doped with dysprosium oxide nanoparticles for generation of white light

A series of zinc borotellurite glass doped with Dy2O3 nanoparticles with chemical formula {[(TeO2)0.7(B2O3)0.3]0.7(ZnO)0.3}1−x(Dy2O3NP)x (where x = 0.01, 0.02, 0.03, 0.04 and 0.05M fraction) has been fabricated by using conventional melt-quenching method. In this work, absorption and emission analysis of the glass systems have been done. The absorption data are obtained from the UV–Vis spectroscopy while the emission spectrum of the glass systems is recorded by using the Luminescence spectrometer. From the absorption data, the direct and indirect optical band gaps for the glass systems are calculated. Both of the band gaps are found to decrease as opposed to the concentration of Dy2O3 nanoparticles. The decrement of the optical band gaps leads to the increment of the refractive index of the glass systems. From the emission spectra, two transition bands are observed, which represent the transition from 4F9/2 to 6H15/2 and 6H13/2. Other than that, the x and y CIE chromaticity coordinates are determined from the emission spectra and are found in the region of white light. The values of the correlated colour temperature for this glass systems are in between 4104.22 and 4886.17K and is in the neutral white light region.

Synthesis and characterization of Dy2O3 nanostructures: enhanced photocatalytic degradation of rhodamine B under UV irradiation

Dysprosium oxide (Dy2O3) nanoparticles have been successfully synthesized via a novel facile solvent-less solid state method. Dysprosium oxide nanostructures were prepared by heat treatment in air at 500 °C for 2 h via Schiff-base ligand as a capping agent and dysprosium source. The effect of the Schiff base ligand (N,N-Bis(salicylidene)ethylenediamine (H2salen)) as a capping agent on product by different molar ratios of dysprosium nitrate and Schiff base ligand were investigated to reach optimum conditions of Dy2O3 nanoparticles such as size and morphology. Analytical method such as Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, X-ray diffraction and UV–Vis diffuse reflectance spectroscopy were employed to characterized the as-prepared nanostructures. The results shows that the molar ration and calcination temperatures of Schiff base ligand and dysprosium nitrate have substantial and key effect on the size and morphology of the Dy2O3. In addition, the photocatalytic activity of Dy2O3 nanostructure was studied by the photocatalytic degradation of the rhodamine B as cationic dye under UV irradiation.

Substrate Decoration for Improvement of Current-Carrying Capabilities of Y0.5Gd0.5Ba2Cu3O x Thin Films by Dy2O3 Nanoparticles

Improved critical current density in Y0.5Gd0.5 Ba2Cu3O7−δ films is achieved by a controlled study of substrate surface modifications with nano-sized second-phase pre-formed Dy2O3 particles. Nanoparticles were applied to buffered Hastelloy substrates using metal organic deposition techniques prior to YGdBCO film growth. With the introduction of Dy2O3 nanoparticles, YGdBCO films showed more robust field dependence and higher flux pinning force at intermediate fields, indicating Dy2O3 surface decoration with metal organic deposition process is a promising method for enhancement of current-carrying capability of YGdBCO film.

Electrocatalytic reduction of CO2 to CO by Gd(III) and Dy(III) complexes; and M2O3 nanoparticles (M = Gd and Dy)

Two Gd(III) and Dy(III) complexes, [M(AyGG)3(H2O)5] (AyGG=Alizarin yellow GG (NaC13H8N3O5)), have been prepared and characterized. The Gd2O3 and Dy2O3 nanoparticles were prepared by the calcination of the Gd(III) and Dy(III) complexes in air at different temperatures. The nanoparticles were characterized by FT-IR, X-ray diffraction analysis (XRD), and field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The voltammograms in the absence and presence of CO2 indicate that the Gd(III) and Dy(III) complexes and their nano-oxides can catalyze the electrochemical reduction of CO2 to CO. The results show that the Dy(III) complex has better electrocatalytic activity than other compounds.

Dual-mode T1 and T2 magnetic resonance imaging contrast agent based on ultrasmall mixed gadolinium-dysprosium oxide nanoparticles: synthesis, characterization, and in vivo application

A new type of dual-mode T1 and T2 magnetic resonance imaging (MRI) contrast agent based on mixed lanthanide oxide nanoparticles was synthesized. Gd3+ (8S7/2) plays an important role in T1 MRI contrast agents because of its large electron spin magnetic moment resulting from its seven unpaired 4f-electrons, and Dy3+ (6H15/2) has the potential to be used in T2 MRI contrast agents because of its very large total electron magnetic moment: among lanthanide oxide nanoparticles, Dy2O3 nanoparticles have the largest magnetic moments at room temperature. Using these properties of Gd3+ and Dy3+ and their oxide nanoparticles, ultrasmall mixed gadolinium-dysprosium oxide (GDO) nanoparticles were synthesized and their potential to act as a dual-mode T1 and T2 MRI contrast agent was investigated in vitro and in vivo. The D-glucuronic acid coated GDO nanoparticles (davg = 1.0 nm) showed large r1 and r2 values (r2/r1 ≈ 6.6) and as a result clear dose-dependent contrast enhancements in R1 and R2 map images. Finally, the dual-mode imaging capability of the nanoparticles was confirmed by obtaining in vivo T1 and T2 MR images.

Facile synthesis, morphology and structure of Dy2O3 nanoparticles through electrochemical precipitation

The aim of this research was to introduce a new, facile and simple method for synthesis of Dy2O3 nanostructures at room temperature. For the first time, galvanostatic electrodeposition was used to synthesize Dy2O3 particles, and the influence of the current density on the structure and morphology of the product was studied. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET). The results show that the current density has little effect on the chemical composition but great effect on the structure and morphology of the samples. The average size of the particles decreases as the applied current density increases. The grain size of as-prepared samples decreases from 500 to 70 nm when the current density increases from 0.5 to 6.0 mA·cm−2. To obtain oxide product, the as-prepared samples were heat-treated at 1,000 °C. The results show that the heat-treated samples have smaller particles. The XRD results show that the similar patterns are observed in the samples synthesized at different current densities, and the only difference from the JCPDS card is the ratio of peak intensities. With the increase in the current density, a decrease in the current efficiency is observed.

A facile approach to synthesize dysprosium oxide nanoparticles

In this report, Dy2O3 (dysprosia) nanoparticles were prepared by using the combustion method. The innovative aspect of this method is preparation of dysprosium oxide nanoparticles without applying calcination temperature. To study the effect of the heating and annealing on the structure of dysprosia, three different calcination temperatures, 450, 550, and 650 °C were applied on the no-calcined sample. TEM and X-ray diffraction XRD were used for characterization of the samples. Diffraction pattern of samples were achieved by selected area electron diffraction (SAED). XRD patterns show the desired cubic structure for all samples. The results of crystallite sizes, estimated by the broadening of XRD peaks, showed the size of crystallites in the range of 24–28 nm. TEM showed the average size of the particles in the range of 28–41 nm.

Synthesis of Dy2O3 nanoparticles via hydroxide precipitation: effect of calcination temperature

This work described the preparation of dysprosium oxide, Dy2O3, nanoparticles using the homogeneous precipitation method. Dy3+ ions were precipitated using NaOH solution. The obtained product was filtered, dried, and then calcined for 1 h at the temperature range of 300–700 °C in static air. The calcination temperature of the Dy-precursor was chosen based on its decomposition as indicated by the TGA analysis. The crystalline structure and surface morphology of the calcined solids were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The obtained results revealed that Dy2O3 with crystallites size of 11–21 nm was formed at 500 °C. Such value increased to 25–37 nm for the sample calcined at 700 °C.