Gd2O3 Nanoparticles Research Articles

Anchoring gadolinium oxide nanoparticles onto CuInZnS: Efficient photocatalytic tetracycline degradation and mechanism analysis

Photocatalysis technology is one of the potential methods to remit the growing issues of environmental pollution. It is of great significance to rationally design high performance antibiotic wastewater degradation catalysts in the whole pH range. In this experiment, Gd2O3 nanoparticles (GdO NPs) were successfully grown onto CuInZnS (CIZS) by a simple hydrothermal method. The introduction of GdO has obvious effects on the nanosheet thickness of CIZS, which reduces carrier transport distances and improves the active sites number of CIZS. What’s more, the SO4•- absorption and electron transfer ability are also greatly optimized. Under 300 W Xe light, tetracycline can be efficient degraded more than 93 % in the whole pH range, which presents absolute advantage compared to CIZS and GdO. Based on the combination of experimental characterization and density functional theory calculations, the proposed photocatalytic tetracycline degradation pathway and mechanism have been given. Moreover, the results of toxicity analysis proved that the CIZS-GdO catalyst could successfully reduce the toxicity of tetracycline wastewater. This work has reference value for the application of rare earth oxides in the field of photocatalysis at full pH range.

The effect of particles size of Gd2O3 on the radiation protection mechanisms of ZnO

There are two mechanisms established for increasing the radiation resistance of optical properties of micron-sized zinc oxide (mZnO) powder modified by gadolinium oxide (nGd2O3) nanoparticles by means of relaxation of the primary radiation defects (electrons and holes): — in atoms of rare-earth element gadolinium; — on Gd2O3 nanoparticles. During modification with gadolinium oxide micron-sized particles, only one (first) mechanism for radiation resistance increasing is enabled. These results are obtained by recording diffuse reflectance spectra in high vacuum in the range of 0.2–2.5 μm under radiation exposure by accelerated electrons (in situ). The established mechanisms for increasing radiation resistance refer not only to the types of powders under the study, but also to other types of oxide semiconductor powders and rare-earth elements. These mechanisms can also be extended to the photo résistance of oxide powders modified by nanoparticles and solid solutions based on them.

On the Possibility of Improving the Oxidation Resistance of High-Chromium Ferritic Stainless Steel Using Reactive Element Oxide Nanoparticles

High-chromium ferritic steels are current the only viable candidates for cheap interconnect materials for application in high-temperature solid oxide fuel and electrolyzer cells (HT-SOFCs/SOECs). The durability and operating characteristics of interconnects manufactured using these materials may be improved significantly by applying a protective-conducting MoCo2O4 coating and depositing an intermediate layer consisting of nanoparticles of Gd2O3—a reactive element oxide—on the surface of the steel substrate. The study demonstrated that the conditions of the thermal treatment of this layered system determine the efficacy of the applied modification with the reactive element. The persistence of this effect was tested over 7000 hours of quasi-isothermal oxidation in air at 800 °C.

Preparation and Characterization of Bilayer Polymer-Dispersed Liquid Crystals Doped with Gd2O3 Nanoparticles and Rhodamine B Base Fluorescent Dye.

Using the polymerization-induced phase separation (PIPS) method, bilayer polymer-dispersed liquid crystal (PDLC) films with a PDLC-PVA-PDLC structure were prepared in this work. It was found that all PDLC performance indexes were affected by polymer mesh size after comparing the microscopic morphology and electro-optical properties of samples with different monomer ratios. Gd2O3 nanoparticles and rhodamine B base fluorescent dyes introduced into the bilayer PDLC optimized the samples' electro-optical properties and developed new functionalities. In addition, the bilayer PDLC doped with Gd2O3 and rhodamine B base held excellent progressive driving functions as well as stable durability properties. Samples doped with Gd2O3 nanoparticles and rhodamine B base also produced excellent anti-counterfeiting effects under UV irradiation at different angles, further exploiting the application potential of PDLC.

Synthesis and characterization of PVP coated gadolinium oxide nanoparticles for imaging applications

In this work, we present the synthesis and applications of Gd2O3@PVP nanoparticles as an efficient contrast agent for MRI and CT techniques. Gd2O3@PVP nanoparticles have been successfully synthesized by the polyol method using ethylene glycol and poly(vinylpyrrolidone) as solvent and surfactant, respectively. The structure, morphology and characteristic properties of the materials are thoroughly investigated by SEM, TEM, UV-Vis, XRD, FTIR and DLS measurements. As an important result, NPs synthesized under optimized conditions have a diameter in the range of 12 nm and exhibit a good contrast signal in magnetic resonance imaging and computed tomography at relatively low concentration ([NPs] = 0.1 mM for MRI and 1.25 mg.mL-1 for CT). In particular, the concentration of Gd2O3@PVP nanoparticles used in CT is 10 times lower than that of the commercial Iobitridol product (i.e., 12.5 mg.mL-1) to achieve similar signal intensity. This result has an important implication for reducing the dose of contrast agent introduced into the body. The obtained results suggest that PVP-coated Gd2O3 nanoparticles can be applied as multifunctional contrast agents for imaging diagnostic applications in the near future.

The effects of modification by Gd2O3 nanoparticles on optical properties and radiation resistance of CaSiO3 powders

The effects of modification by Gd2O3 nanoparticles on optical properties and radiation resistance of CaSiO3 powders

NSF evaluation of gadolinium biodistribution in renally impaired rats: Using novel metabolic Gd2O3 nanoparticles coated with β-cyclodextrin (Gd2O3@PCD) in MR molecular imaging

The use of conventional gadolinium(Gd)-based contrast agents in magnetic resonance imaging (MRI) poses a significant risk of Nephrogenic Systemic Fibrosis (NSF) syndrome in patients with impaired renal function (grades 4 and 5). To address this issue, a new study has introduced a novel metabolic Gadolinium oxide nanoparticle (Gd2O3 NPs) coated with β-cyclodextrin (βCD). The study aims to investigate NSF syndrome by quantifying tissue Gd deposition biodistribution in renal impairment rats using MR molecular imaging. This is the first study of its kind to use this approach.A group of 20 rats were divided into four groups, each containing five rats that underwent 5/6 nephrectomy. The rats received 12 intravenous injections of a novel homemade synthesized gadolinium oxide polycyclodextrin (Gd2O3@PCD) at a dose of 0.1 mmol/kg, conventional contrast agents (CAs) drugs of Omniscan (Gd-DTPA-BMA) and Dotarem (Gd-DOTA), at a dose of 2.5 mmol/kg, and 250 μl saline for two injections per week during six weeks. T1-weighted MR imaging was performed before the injections and once a week for six weeks to quantify Gd deposition in four different organs (skin, liver, heart, and lung) in rats using inductively coupled plasma mass spectrometry (ICP-MS). The relationship between Signal-to-Noise Ratio (SNR) and biodistribution of Gd deposition due to NSF-induced syndrome was also calculated.The results of the study showed that the Gd concentrations in tissues were significantly higher in the Gd2O3@PCD group compared to the other groups, without any significant histopathological changes (P < 0.05). In the Gd2O3@PCD group, Gd was mainly deposited in the skin, followed by the liver, lung, and heart, without any symptoms of thickening or hardening of the skin. The Gd concentrations in the skin, liver, lung, and heart were significantly lower in the Dotarem group than in the Omniscan group (P < 0.05). In the histopathological examinations, the Omniscan group showed increased cellularity in the dermis. A significant hyperintensity was observed in the Gd2O3@PCD-treated rats compared to the Dotarem and Omniscan groups in the liver, heart, and lung.Compared to conventional Gd-based CAs, the novel metabolically Gd2O3@PCD with increased SNR, biosafety, and a considerably lower probability of developing NSF, has potential applicability for diagnosing patients with renal diseases in clinical MR Molecular Imaging (MRMI).

Gd2O3–Carbon Nanoflakes (CNFs) as Contrast Agents for Photon-Counting Computed Tomography (PCCT)

2–3 nm Gd2O3 nanoparticles deposited on carbon nanoflakes were prepared. These are new contrast agents for photon-counting computed tomography based on detectors allowing counting of separate photons. Contrast agents of the Gd2O3@C core–shell structure were prepared by graphitization of the surface of these particles. The Gd2O3 and Gd2O3@C nanoparticles obtained, aqueous solution of Gd(NO3)3·6H2O, and a dispersion of 300–500 nm Gd2O3 particles in gelatin were studied by photon-counting computed tomography. At equal gadolinium concentrations, the highest X-ray absorption was noted for Gd(NO3)3·6H2O and Gd2O3, which is associated with higher density of these samples. Carbon in the contrast agents does not affect the absorption. An algorithm was developed for semiquantitative determination of gadolinium by photon-counting computed tomography.

Gd2O3 nanoparticles prepared by spark discharge method: Structure and magnetocaloric properties

Several batches of nanoparticles of gadolinium oxide Gd2O3 were obtained by the electrophysical spark discharge (ESD) method using selected variations of the value of the energy supplied to the discharge gap. The change of the charge voltage led to a change in the energy supplied to the discharge gap in the range of 3 J to 55 J. The average size of spark discharge nanoparticles in all cases was close to 8 nm in accordance with low-temperature nitrogen adsorption data. Gd2O3 nanoparticles contained two crystalline phases (cubic and monoclinic), the amount of which varied within certain limits by changing the parameters of the spark discharge. The obtained maximum values of the magnetic entropy change ΔSM of the studied ESD Gd2O3 nanoparticles with a monoclinic phase content of less than 40 wt% are not inferior to the value of ΔSM of Gd2O3 nanoparticles obtained by chemical methods. The spark discharge technique seems to be a promising technology for manufacturing of gadolinium oxide nanoparticles applications for the magnetic cooling systems of cryogenic refrigeration.

Nanocomposite based on Gd2O3 nanoparticles and drug 5-fluorouracil as potential theranostic nano-cargo system

We have prepared silica matrix with hexagonal symmetry of pores (SBA-15) and loaded it with anticancer drug 5-Fluorouracil (5-FU) to promote it as a drug delivery system. Gd2O3 nanoparticles were incorporated into the matrix to enhance nanosystems applicability as contrast agent for MRI, thus enabled this nanocomposite to be used as multifunctional nano-based therapeutic agent. Drug release profile was obtained by UV-VIS spectroscopy, and it indicates the prolongated release of 5-FU during the first hours and the total release after 5 h. The cytotoxicity tests using MTT-assay, fluorescent microscopy, bright-field microscopy, and flow cytometry were carried out using human glioma U87 MG cells and SK BR 3 cells. The nanocomposite with anticancer drug (Gd2O3/SBA-15/5FU) showed toxic behaviour towards studied cells, unlike nanocomposite without drug (Gd2O3/SBA-15) that was non-toxic. Our drug delivery system was designed to minimalize negative effect of Gd3+ ions at magnetic resonance imaging and drug 5-FU on healthy cells due to their encapsulation into biocompatible silica matrix, so the Gd3+ ions are more stable (in comparison to chelates), lower therapeutic dose of 5-FU is needed and its prolongated release from silica pores was confirmed. Very good T1 contrast in MR images was observed even at low concentrations, thus this nanosystem can be potentially used as contrast imaging agent.

Leveraging 3D Bioprinting and Photon-Counting Computed Tomography to Enable Noninvasive Quantitative Tracking of Multifunctional Tissue Engineered Constructs.

3D bioprinting is revolutionizing the fields of personalized and precision medicine by enabling the manufacturing of bioartificial implants that recapitulate the structural and functional characteristics of native tissues. However, the lack of quantitative and noninvasive techniques to longitudinally track the function of implants has hampered clinical applications of bioprinted scaffolds. In this study, multimaterial 3D bioprinting, engineered nanoparticles (NPs), and spectral photon-counting computed tomography (PCCT) technologies are integrated for the aim of developing a new precision medicine approach to custom-engineer scaffolds with traceability. Multiple CT-visible hydrogel-based bioinks, containing distinct molecular (iodine and gadolinium) and NP (iodine-loaded liposome, gold, methacrylated gold (AuMA), and Gd2 O3 ) contrast agents, are used to bioprint scaffolds with varying geometries at adequate fidelity levels. In vitro release studies, together with printing fidelity, mechanical, and biocompatibility tests identified AuMA and Gd2 O3 NPs as optimal reagents to track bioprinted constructs. Spectral PCCT imaging of scaffolds in vitro and subcutaneous implants in mice enabled noninvasive material discrimination and contrast agent quantification. Together, these results establish a novel theranostic platform with high precision, tunability, throughput, and reproducibility and open new prospects for a broad range of applications in the field of precision and personalized regenerative medicine.

Production and investigation of 3D printer ABS filaments filled with some rare-earth elements for gamma-ray shielding

Radiation is the main safety issue for almost all nuclear applications, which must be controlled to protect living organisms and the surrounding materials. In this context, radiation shielding materials have been investigated and used in nuclear technologies. The choice of materials depends on the radiation usage area, type, and energy. Polymer materials are preferred in radiation shielding applications due to their superior characteristics such as chemical inertness, resistivity, low weight, flexibility, strength, and low cost. In the presented work, ABS polymer material, which is possibly the most commonly used material in 3D printers, is mixed with Gd2O3 and Er2O3 nanoparticles. ABS filaments containing these rare-earth elements are then produced using a filament extruder. These produced filaments are used in a 3D printer to create shielding samples. Following the production of shielding samples, SEM, EDS, and gamma-ray shielding analyses (including experiments, WinXCOM, GEANT4, and FLUKA) are performed. The results show that 3D printing technology offers significant enhancements in creating homogeneous and well-structured materials that can be effectively used in gamma-ray shielding applications.

Structure and magnetic properties of Gd2O3 nanoparticles obtained by the spark discharge method

Gadolinium oxide nanoparticles were obtained by the spark discharge electrophysical method. Structure, magnetic and magnetocaloric properties of Gd2O3 nanoparticles are comparatively analyzed. According to X-ray phase analysis, the synthesized Gd2O3 nanoparticles contain two crystallographic phases: cubic and monoclinic. The change in the magnetic part of the entropy dSM was determined from the measurement data of magnetic isotherms based on the Maxwell relation. The maximum value of dSM for a magnetic field variation amplitude of 2 T was approximately 17 J/kgK and was observed at a temperature of 2.5 K.

Doped Multiple Nanoparticles with Hydroxyapatite Coating Show Diverse Health Effects in vivo.

The lack of osteoinductive, angiogenic and antimicrobial properties of hydroxyapatite coatings (HA) on titanium surfaces severely limits their use in orthopedic and dental implants. Therefore, we doped SiO2, Gd2O3 and CeO2 nanoparticles into HA to fabricate a HASiGdCe coating with a combination of decent antibacterial, angiogenic and osteogenic properties by the plasma spraying technique. The HASiGdCe coating was analyzed by SEM (EDS), surface roughness tests, contact angle tests, XRD, FTIR spectroscopy, tensile tests and electrochemical dynamic polarization tests. Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PAO-1) were used as representative bacteria to verify the antibacterial properties of the HASiGdCe coating. We evaluated the cytocompatibility and in vitro osteoinductivity of the HASiGdCe coating by investigating its effect on the cell viability and osteogenic differentiation of MC3T3-E1 cells. We assessed the in vitro angiogenic activity of the HASiGdCe coating by migration assay, tube formation assay, and RT‒PCR analysis of angiogenic genes in HUVECs. Finally, we used infected animal femur models to investigate the biosafety, antimicrobial and osteointegration properties of the HASiGdCe coating in vivo. Through various characterization experiments, we demonstrated that the HASiGdCe coating has suitable microscopic morphology, physical phase characteristics, bonding strength and bioactivity to meet the coating criteria for orthopedic implants. The HASiGdCe coating can release Gd3+ and Ce4+, showing strong antibacterial properties against MRSA and PAO-1. The HASiGdCe coating has been shown to have superior osteogenic and angiogenic properties compared to the HA coating in in vitro cellular experiments. Animal implantation experiments have shown that the HASiGdCe coating also has excellent biosafety, antimicrobial and osteogenic properties in vivo. The HASiGdCe coating confers excellent antibacterial, angiogenic and osteogenic properties on titanium implants, which can effectively enhance implant osseointegration and prevent bacterial infections, and it accordingly has promising applications in the treatment of bone defects related to orthopedic and dental sciences.

Structure and Magnetic Properties of Gd2O3 Nanoparticles Synthesized by Spark Discharge

Structure and Magnetic Properties of Gd2O3 Nanoparticles Synthesized by Spark Discharge

Electronic and Band Gap Structure of Cd-Doped Gadolinium Oxide: A DFT Based Theoretical Study

The optical uses of Gd2O3 have attracted interest in optoelectronics and have increased its popularity in industry. With the use of density functional theory, the SCF, band structure and density of states of cubic Gd2O3are examined. For this,we create a Gd2O3 supercell with a scaling of (211) andexamine the electronic characteristics such as band gap and DOS by using DFT. The influence of Cd doping on morphologicaland electrical characteristics of Gd2O3 nanoparticles is also described in the current study, and the modified properties of Gd2O3 are subsequently examined at the supercell level by employing DFT. Calculations indicates that SCF is converged with total energy -689.288RY. After the convergence of SCF,a direct band gap has been found by computing the electrical band structure. This paper also show that cd doping has a massive effect on the gadolinium oxide structure. The results of lattice constants are found to be credible. In all polymorphic phases, Gd2O3 is ductile and mechanically stable.

Facile fabrication and technical analysis of copper doped Gd2O3 nanoparticles: Photocatalytic elimination of Rhodamine B dye under UV light

The current study concentrates on the facile fabrication of copper doped Gd2O3 nanoparticles by facile chemical route. The materials were characterized by XRD, FTIR, PSA, SEM, EDAX and UV-visible spectroscopy. The optical band gap (Eg) was found to be in the range of 3.10–4.29 eV. The materials exhibited better photocatalytic efficiency in degrading Rhodamine B (RhB) under UV light. Among the materials studied, 0.075 g Gd1.70Cu0.30O3-δ photocatalyst material has degraded 82% of RhB at a pH of 4.3 in 80 min.

Effects of Mn doping on the structural, linear and nonlinear optical properties of Gd2O3 nanoparticles

We report on the effects of Mn doping on the structural, linear, and nonlinear optical properties of Gd2-xMnxO3 nanoparticles (x = 0.00, 0.03, 0.05, and 0.10). The Gd2-xMnxO3 powders were prepared using sol-gel process. The x-ray diffraction technique shows that the Mn3+ doping results in a small decrease in lattice parameter and an increase in crystallite size. UV–visible measurements were carried out in the wavelength range of 200–800 nm. The direct optical band gap estimated using Tauc model decreases with increasing Mn content from 5.152 to 5.008 eV, while Urbach energy increases from 0.753 to 1.012 eV. Moreover, the insertion of Mn results in a significant enhancement in the optical parameters (refractive index, extinction coefficient, absorption coefficient, dielectric constants (ε', ε"), optical and electrical conductivity. The dispersion energy (Ed) increases from 24.13 to 30.1 eV, while the single oscillator energy (E0) declines lightly from 10.28 to 9.998 eV with the increase of Mn content. With Mn doping an enhancement in the static linear refractive index (n0) and high-frequency dielectric constant (ε∞) were also observed. Analysis of linear and nonlinear optical parameters shows that the presence of manganese enhanced the linear optical susceptibility (χ(1)), third-order non-linear susceptibility (χ(3)), and non-linear refractive index (n2). These optical results show the potential applications of Gd2-xMnxO3 nanoparticles (x = 0.00, 0.03, 0.05 and 0.10) in various optical devices.

Optical and structural properties of H-BN@Gd2O3 nanoflake prepared by laser–induced ablation in liquid

In this paper, we reported the synthesis of hexagonal BN, Gd2O3 nanoparticles, and BN@Gd2O3 hybrid nanocomposites by novel laser ablation in liquid. Several analytical techniques including x-ray diffraction (XRD), UV–vis spectroscopy, Fluorescence spectroscopy, Field Emission Scanning electron Microscopy (FE-SEM) with Energy dispersive spectroscopy (EDS), High-resolution transmission electron microscope (HR-TEM), and map imaging were used to investigate the structural and optical properties of synthesized nanoparticles. According to FE-SEM and TEM results, FE-SEM images show the formation of h-BN NPs, sheet-like, and spherical nanoparticles, hexagonal-type nanoflake of Gd2O3, and needle-like shapes. High-resolution transmission electron microscopy images confirm that the average diameter of all samples is ∼40 nm. However, the length of the nanorods is found to vary from 50 nm to 240 nm. The optical properties studies show that the optical energy gap of h-BN, Gd2O3, and h-BN@Gd2O3 is in the range of (4.5–5.5) eV.

Er-doped gadolinium oxide nanoparticles for enhanced UV-VIS energy conversion: Structural features, optical properties and quantum efficiency

We present comprehensive study of the UV-VIS energy conversion in Gd2O3:Er nanoparticles. Based on our previous research, it was shown that Gd2O3:Er nanoparticles are promising for energy applications due to alternative channel of UV-VIS conversion through the Gd3+def →Er3+ energy transfer. However, a number of important issues, such as the influence of the structural features of the matrix (defectiveness and nonequivalence of cation positions) as well as the concentration of the activator ion on the processes of excitation-relaxation, were poorly understood. In this work we established and explained the mechanisms and regularities of UV-VIS energy conversion in Gd2O3:Er with a wide range of Er3+ concentration (0,25-8%).It was shown that with an increase in the Er3+ ion concentration, the mechanism of Gd3+def →Er3+ energy transfer changes from dipole-quadrupole interaction to exchange interaction due to a decrease in the average donor-acceptor distance. The evolution of the temperature dependences of Er3+ luminescence revealed two structurally (C2 and S6 positions in cubic Gd2O3) and energetically non-equivalent donor Gd3+def ions. It was determined that the distortions in the local environment of Gd3+def ions lead to the transformation of the barrier for emission quenching from discrete to dispersed distribution. The final efficiency of a complex UV-VIS conversion process was obtained accounting a number of factors: role of different channels of Er3+ excitation; bimodal distribution of energy barrier for emission quenching and influence of phonon states on non-radiative losses. The results demonstrate new possibilities for improving the functional characteristics of Gd2O3 nanoparticles for energy conversion devices. As one of the possible practical applications of the results of work, we made and tested prototypes of Si/Gd2O3:Er cells with enhanced efficiency of photovoltaic energy conversion.