Gd2O3 Nanoparticles Research Articles

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.

Preparation of reverse mode polymer dispersion liquid crystals with vertically oriented layers and the electro-optical properties

ABSTRACT The reverse-mode polymer dispersed liquid crystals (re-mode PDLC) are feasible to be prepared by polyimide vertically oriented layers. The indium tin oxide (ITO) glass coated with polyimide-oriented layer was prepared by centrifugal spin coating and high temperature curing, and the re-mode PDLC film was prepared by polymerisation-induced phase separation method. After that the effects of diluent, negative liquid crystal and gadolinium oxide (Gd2O3) nanoparticle content on the morphology and electro-optical properties of re-mode PDLC were comprehensively investigated. The results show that the re-mode PDLC with appropriate diluent and negative liquid crystal content has stable contrast ratio and driving voltage, and the re-mode PDLC samples doped with Gd2O3 nanoparticles can further increase the contrast ratio to improve the problem of low contrast of ordinary re-mode PDLC samples. In the thermal ageing life test, the driving voltage ageing degree of the nanoparticle-doped re-mode PDLC samples can be stabilised, which has some significance for use of re-mode PDLC.

Architecting the Z-scheme heterojunction of Gd2O3/g-C3N4 nanocomposites for enhanced visible-light-induced photoactivity towards organic pollutants degradation.

A basic calcination process in one step was employed to create g-C3N4 photocatalytic composites modified by Gd2O3 nanoparticles. SEM (scanning electron microscopy), FTIR (Fourier-transform infrared spectroscopy), XRD (X-ray diffraction), EIS (electrochemical impedance spectroscopy), PL (photoluminescence studies) as well as TEM (transmission electron microscopy), XPS (X-ray photoelectron spectroscopy), and CV (cyclic voltammetry) were employed to explain the structural traits, optical properties, and morphological features of the processed photocatalyst. The findings show that Gd2O3(Gd) does not affect the sample's crystalline structure but rather increases g-C3N4 surface area by spreading it superficially. Furthermore, Gd can redshift the light absorption peak, reduce the energy gap, and improve the efficiency with which photogenerated holes and electrons are removed in g-C3N4. The surfacemorphology of g-C3N4, in particular, could be significantly enhanced. We similarly employed three distinct photocatalytic complexes of Gd2O3 and g-C3N4 in 1:1, 2:1, and 3:1 proportions to degrade methylene blue (MB). After 100min in visible light (400-800nm), the photodegradation rate of composites is 58.8% for 1:1 (GG1), 94.5% for 2:1 (GG2), and 92% for 3:1(GG3). In addition to the MB dye, thephotocatalytic activity of synthesized materials was also studied for methyl orange. The result shows phenomenal degradation values, i.e.; for GG1 86%, GG2 96%, and for GG3 84.6%. The narrow band gap that separates the photogenerated electron and hole enhances g-C3N4 ability to degrade photo-catalytically. From the result, we concluded that the photocurrent and cyclic photocatalytic degradation of methylene blue shows that a composition of 2:1 Gd2O3/g-C3N4 has high photocatalytic stability.

Structural and optical characterisation of silanised Dy-doped-Gd2O3 NPs.

In this work, we studied the optical properties of Dy-doped Gd2O3 nanoparticles (NPs) before and after their APTES functionalisation. We obtained luminescent Dy@Gd2O3 NPs (0.5, 1, and 5% mol) using a modified polyol method. Our work describes their detailed structural analysis using FT-IR, XRD, HRTEM, TGA and XAS techniques. The results show that these systems present a crystalline structure with a body-centred cubic cell and particle sizes of 10 nm. The dopant position was inferred as substitutional, through XAS analysis at the M4,5-edges of Gd and Dy and K-edge of O, and in C2 sites, based on photoluminescence studies. There was sensitization of the luminescence by the matrix as shown by the emission increase of the hypersensitive transition (6F9/2 → 6H13/2, 572 nm) and also a broadband appears around 510 nm attributed to defects in Gd2O3. An enhanced emissive lifetime of 398 μs was found for the sample doped at 1%. We functionalised the Dy@Gd2O3 (at 1%) NPs with 3-aminopropiltrietoxisilane (APTES) for further application as a biomarker sensor. We found that these NPs conserved their luminescence after adding the surface agent (avoiding quenching effects) making them potential materials for biosensing.

The Use of a Suspension of Functionalized Gadolinium Oxide Nanoparticles for Photocatalytic Applications

Photo-degradation of Rhodamine B (RhB) in aqueous solution was use as a probe to assess the photocatalytic activity of Gadolinium oxide (Gd2 O3 ) nanoparticles in suspension under UV irradiation. The nanoparticles in suspension were prepared by a polyol method using gadolinium chloride hexahydrate (Gd2 Cl6 .6H2 O) and diethylene glycol (DEG) as starting precursors. The physico-chemical properties of the elaborated suspension are analyzed using X-ray diffraction (XRD), ultraviolet visible (UV-vis) and infrared (FTIR) spectroscopies, transmission electron microscopy (TEM) and viscosimetry. The Gd2 O3 nanoparticles in suspension were used as photocatalyst for the degradation of Rhodamine B (RhB) dye under irradiation with UV light. The results of the kinetic studies showed that the photodegradation reactions were followed by a pseudo first order reaction rate law over the first 30 minutes of monitoring. The elaborated Gd2 O3 nanoparticles suspension showed a great efficiency in the photocatalytic test without any addition of a co-catalyst, thus limiting the complexity of the further decontamination process of waste water.

3-Mercaptopropyl Trimethoxysilane @ Gadolinium Oxide Nanoprobes: An Effective Fluorescence-Sensing Platform for Cysteine

The current work aims to synthesize highly fluorescent and surface-functionalized gadolinium oxide nanoparticles (Gd2O3 NPs) with (3-mercaptopropyl) trimethoxysilane (MPTMS). The surface modification of Gd2O3 nanoparticles with MPTMS enhanced the stability and solubility of the nanoprobe in aqueous media. The size of the nanoprobe was controlled to 7 ± 1 nm using MPTMS coating. These valued points made the MPTMS@Gd2O3 nanoparticles as economical, highly sensitive, selective nanoprobe with a quick response time for the detection of cysteine via the simple fluorescence-based methodology. The proposed strategy has offered the reliable detection of cysteine in the concentration range of 1–100 µm with a detection limit of 42 nm. The selective sensing of cysteine in human serum has jointly acknowledged the potential prospect of developing sensors in body fluids with great accuracy.

Mono and Multiple Tumor-Targeting Ligand-Coated Ultrasmall Gadolinium Oxide Nanoparticles: Enhanced Tumor Imaging and Blood Circulation.

Hydrophilic and biocompatible PAA-coated ultrasmall Gd2O3 nanoparticles (davg = 1.7 nm) were synthesized and conjugated with tumor-targeting ligands, i.e., cyclic arginylglycylaspartic acid (cRGD) and/or folic acid (FA). FA-PAA-Gd2O3 and cRGD/FA-PAA-Gd2O3 nanoparticles were successfully applied in U87MG tumor-bearing mice for tumor imaging using T1 magnetic resonance imaging (MRI). cRGD/FA-PAA-Gd2O3 nanoparticles with multiple tumor-targeting ligands exhibited higher contrasts at the tumor site than FA-PAA-Gd2O3 nanoparticles with mono tumor-targeting ligands. In addition, the cRGD/FA-PAA-Gd2O3 nanoparticles exhibited higher contrasts in all organs, especially the aorta, compared with those of the FA-PAA-Gd2O3 nanoparticles, because of the blood cell hitchhiking effect of cRGD in the cRGD/FA-PAA-Gd2O3 nanoparticles, which prolonged their circulation in the blood.

Embedding Gd2O3 nanoparticles hydrothermally prepared in a Fe3O4 shell and surface modification with a dextrose bio capping agent

The present work describes a multi-stage processing method for the hydrothermal synthesis of gadolinium oxide (Gd2O3) nanoparticles and subsequent surface modification with iron oxide (Fe3O4) and dextrose. To prepare gadolinium oxide nanoparticles, gadolinium chloride was reacted with sodium hydroxide, and the resulting precipitate was autoclaved. Subsequently, the product was calcined. Afterward, Gd2O3 nanoparticles were coated with a Fe3O4 nanolayer synthesized via coprecipitation, and the resulting core-shell nanocomposites were encapsulated in a dextrose capping agent for enhanced biocompatibility. The effect of various Gd2O3 synthesis parameters on particle size, structure, and magnetic properties was then investigated. These parameters included preliminary precipitation temperature (25, 90 °C) and stirring speed (400, 1000 rpm), hydrothermal temperature (150 and 180 °C) and pressure (5 and 10 bar), and final calcination temperature (600 and 1000 °C). For the investigation of nanocomposites, X-ray diffraction (XRD), scanning and transmission electron microscopy, dynamic laser scattering (DLS), Fourier-Transform infrared spectroscopy (FTIR), and magnetometry (VSM) techniques were used, while the viability of colloidal samples was determined using the MTT-assay method. The results indicated that increasing the steering speed and temperature of the precipitation process and raising the calcination temperature reduced the size of Gd2O3 nanoparticles. Autoclave dehydration had no discernible effect on Gd2O3 nanoparticles. TEM and SEM images confirmed the core/shell structure of Gd2O3/Fe3O4. The shell thickness of 74–95 nm core nanoparticles was in the range of 30–40 nm. With a saturation magnetization of 3.4 emu/g, the nanoparticles exhibited paramagnetic behavior. The 48-h MTT assay demonstrated excellent biocompatibility up to 285 μg solid concentrations containing 24.5 μg [Fe] and 91.2 μg [Gd], with viability remaining greater than 50% at 400 μg solid concentration.

Gd2O3/b-TiO2 composite nanoprobes with ultra-high photoconversion efficiency for MR image-guided NIR-II photothermal therapy.

Photothermal therapy (PTT), as an important noninvasive and effective tumor treatment method, has been extensively developed into a powerful cancer therapeutic technique. Nevertheless, the low photothermal conversion efficiency and the limited tissue penetration of typical photothermal therapeutic agents in the first near-infrared (NIR-I) region (700-950nm) are still the major barriers for further clinical application. Here, we proposed an organic/inorganic dual-PTT agent of synergistic property driven by polydopamine-modified black-titanium dioxide (b-TiO2@PDA) with excellent photoconversion efficiency in the second NIR (NIR-II) region (1000-1500nm). More specifically, the b-TiO2 treated with sodium borohydride produced excessive oxygen vacancies resulting in oxygen vacancy band that narrowed the b-TiO2 band gap, and the small band gap led to NIR-II region wavelength (1064nm) absorbance. Furthermore, the combination of defect energy level trapping carrier recombination heat generation and conjugate heat generation mechanism, significantly improved the photothermal performance of the PTT agent based on b-TiO2. The photothermal properties characterization indicated that the proposed dual-PTT agent possesses excellent photothermal performance and ultra-high photoconversion efficiency of 64.9% under 1064nm laser irradiation, which can completely kill esophageal squamous cells. Meanwhile, Gd2O3 nanoparticles, an excellent magnetic resonance imaging (MRI) agent, were introduced into the nanosystem with similar dotted core-shell structure to enable the nanosystem achieve real-time MRI-monitored cancer therapeutic performance. We believe that this integrated nanotherapeutic system can not only solve the application of PTT in the NIR-II region, but also provide certain theoretical guidance for the clinical diagnosis and treatment of esophageal cancer.

Effect of thermal exposure on microstructure evolution and mechanical properties of cast beta-solidifying TiAl-based alloy doped with Gd

Evolution of an initial nearly-lamellar (γ+α2+β0) structure of a new cast β-solidifying TiAl-based alloy Ti-44.5Al-2V-1Nb-2Cr-0.1Gd (at.%) after isothermal exposures at 800 °C for up to 10,000 h has been systematically investigated using SEM, TEM, EDS, and XRD analyses. During the exposures the alloy microstructure degraded by the α2 laths and β0 phase dissolution, resulting in coarsening of lamellar structure and rising of the γ phase volume fraction. A 2.5- and 3-fold increase in the number of nano-sized gadolinium oxide (Gd2O3) particles have been observed after 10,000-h exposure in lamellar colonies and in grain boundaries, respectively. The gadolinium oxides had monoclinic (C2/m) and cubic (Ia-3) structures and precipitated predominantly along γ/α2 and γ/β0 interfaces and inside the γ lamellae. Furthermore, the applied creep loading was found to contribute significantly to the precipitation process of Gd2O3 nano-particles, since dislocation networks being the sites for their preferred formation. Nanohardness of the γ phase increased from 4.4 ± 0.3 to 5.0 ± 0.4 GPa after the exposures, but no changes were observed for the β0 phase. As a result of structure evolution the tensile strengths reduced by 10–12 and 11–14 % measured at 20 and 750 °C testing temperatures, respectively. Meanwhile, the plastic elongation values remained essentially unchanged. We interpret this as insignificant effect of the precipitation of Gd-rich oxide nano-particles on the alloy ductility.

Gadolinium-oxide nanoparticles for cryogenic magnetocaloric applications

The series of advanced nanocomposites consisting of Gd2O3 nanoparticles (NPs) embedded into periodic porous SiO2 matrix have been investigated with respect to their structural and magnetocaloric properties. By means of small angle neutron scattering and transmission electron microscopy, regular nanopores organized in the cubic or hexagonal superlattice have been documented. The pores are occupied by the NPs of progressive concentration within the nanocomposite series. All of the examined systems have exhibited extraordinarily high values of magnetic entropy change (up to 70 J kg−1 K−1) at low temperatures with the absence of thermal hysteresis, indicating their perspective utilization in cryogenic refrigeration. Profound analysis of magnetic entropy change data via scaling laws has been applied to the nanocomposite materials for the very first time. With the aid of scaling analysis, conclusions on magnetic properties and phase transition type have been made, even for the conditions unavailable in the laboratory.

Highly-sensitive and selective non-enzymatic L-cysteine sensor based on 3-mercaptopropyl trimethoxysilane functionalized Gd2O3 nanoparticles

Herein, we report a facile fabrication of (3-mercaptopropyl) trimethoxysilane (MPTMS) functionalized gadolinium oxide nanoparticles (Gd2O3 NPs) and their application in sensing of L-Cysteine (L-Cys). The main purpose of MPTMS was to restrict the size in 6–8 nm range with better control on the morphology and surface activities of Gd2O3 NPs. Additionally, the electro-catalytic and surface properties of MPTMS@Gd2O3 NPs were explored for the selective and sensitive detection of L-Cys by using cyclic voltammetric (CV), chronoamperometric (CA) and differential pulse voltammetric (DPV) techniques. The as formed sensor displayed a good linear response between 1 and 100 µM and possessed high peak current intensity for electro-oxidation of L-Cys with a detection limit of 30 nM. The scope of the sensor was also assessed in the presence of different interfering species. The outcomes suggested the high stability, reproducibility and electro-catalytic activity of MPTMS@Gd2O3/Au sensor. The applicability of as formed sensor in spiked human urine samples has further increased the potential prospective of developed sensor in biomedical field with good recovery rate.

UV Light Photo-Degradation of Rhodamine B and Methylene Blue Dyes using Gd2O3 Nanoparticles

The detoxification of numerous harmful and toxic contaminants as well as water treatment is done successfully by photocatalytic oxidation. The potential uses of metal oxide, which are defined as charge carriers in electronic structure, enhance its light-absorbing qualities when exposed to a particular type of radiation and enable its use as a photocatalyst. Metal oxide nanoparticles, as photocatalyst, are used in waste-water treatment in removing pollutants and the degradation of dyes, thus can render water reusable. In the current investigation, XRD and SEM studies were utilized to analyze the rare earth Gd2O3 nanoparticles that were synthesized using the chemical precipitation approach. Additionally, degradation of Rhodamine B and methylene blue in aqueous solution under UV light was used to assess the photocatalytic activity. The results indicated that the synthesized Gd2O3 material exhibits good photocatalytic activity.

Structural and photoluminescence studies of Gd2O3 doped with Ln3+ (Ln = Eu/Tb) and sensitised with Li+/Bi3+

A facile direct precipitation method was used for the synthesis of Gd2O3 based luminescence nanoparticles. Eu3+ and Tb3+ doped nanoparticles co-doped with Li+/Bi3+ were prepared by wet chemical route at a relatively low temperature of 120 °C followed by annealing at 500 and 900 °C for 2 h. A series of red and green colour emitting phosphors have been developed. The syntrhesised nanoparticles are studied using various characterisation techniques like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Transmission electron microscopy (TEM) and Photoluminescence (PL) spectroscopy. These characterisation provides the insight of structural and optical properties of the material. Both Eu3+ and Tb3+ doped samples exhibit strong emission on UV light excitation. The role of sensitisers like Li+/Bi3+ are studied in detail. The synthesized nanoparticles Gd2O3:Ln3+ (Ln = Eu/Tb) and Gd2O3:Ln3+ co-doped with Li+/Bi3+ nanoparticles can be used in many fluorescent materials, luminescence, and electroluminescent devices.

Sub-100 nm and ultra-thin hollow Gd2O3 nanospheres for effective magnetic resonance imaging T1 contrast agent

Gd2O3 nanomaterials with the highly exposed surface are proved to be effective magnetic resonance imaging (MRI) T 1 contrast agents. Most research efforts are focusing on ultra-small Gd2O3 nanoparticles, while sub-100 nm hollow Gd2O3 nanospheres with the ultra-thin shell are another strategy that can be more advantageous to prevent fast renal clearance and enhance cancer-targeted accumulation. Although there have been many reported methods for the synthesis of hollow nanospheres of various materials, the synthesis of Gd2O3 with an ultra-thin shell has not been achieved previously. In this article, we demonstrate a successful strategy for the synthesis of ultra-thin Gd2O33 hollow nanospheres (HNS) with adjustable size and shell thickness through a SiO 2 nanoparticle templating method. The 30 nm Gd2O3 hollow nanospheres with a shell thickness of 2.9 nm showed high MRI T 1 relaxivity with an r 1 value of 3.77 mM − 1 s − 1 at 7 T.

A comprehensive Monte Carlo study to design a novel multi-nanoparticle loaded nanocomposites for augmentation of attenuation coefficient in the energy range of diagnostic X-rays

Abstract Introduction: The present study aimed to investigate the radiation protection properties of silicon-based composites doped with nano-sized Bi2O3, PbO, Sm2O3, Gd2O3, WO3, and IrO2 particles. Radiation shielding properties of Sm2O3 and IrO2 nanoparticles were investigated for the first time in the current study. Material and methods: The MCNPX (2.7.0) Monte Carlo code was utilized to calculate the linear attenuation coefficients of single and multi-nano structured composites over the X-ray energy range of 10–140 keV. Homogenous distribution of spherical nanoparticles with a diameter of 100 nm in a silicon rubber matrix was simulated. The narrow beam geometry was used to calculate the photon flux after attenuation by designed nanocomposites. Results: Based on results obtained for single nanoparticle composites, three combinations of different nano-sized fillers Sm2O3+WO3+Bi2O3, Gd2O3+WO3+Bi2O3, and Sm2O3+WO3+PbO were selected, and their shielding properties were estimated. In the energy range of 20-60 keV Sm2O3 and Gd2O3 nanoparticles, in 70-100 keV energy range WO3 and for photons energy higher than 90 keV, PbO and Bi2O3 nanoparticles showed higher attenuation. Despite its higher density, IrO2 had lower attenuation compared to other nanocomposites. The results showed that the nanocomposite containing Sm2O3, WO3, and Bi2O3 nanoparticles provided better shielding among the studied samples. Conclusions: All studied multi-nanoparticle nanocomposites provided optimum shielding properties and almost 8% higher attenuation relative to single nano-based composites over a wide range of photon energy used in diagnostic radiology. Application of these new composites is recommended in radiation protection. Further experimental studies are suggested to validate our findings.

3D sub-cellular localization of upconverting nanoparticles through hyperspectral microscopy

Hyperspectral microscopy is an intriguing technique combining spectroscopy with optical microscopy that can be used to simultaneously obtain spectral and spatial information. The relevance of hyperspectral imaging in biomedical applications such as the monitoring of bioimaging agents, the identification of pathogens and cancerous cells, and the cellular uptake of nanoparticles has emerged recently, due to recent advances in optical reconstruction. The location and tracking of particles within the cell structure have been analyzed by 2D hyperspectral imaging of non-fluorescence objects, being examples of 3D localization uncommon. Here, we report the synthesis of Yb3+/Er3+-codoped Gd2O3 nanoparticles, their structural and luminescence characterization, and their biocompatibility assessments in Human melanoma (MNT-1 and A375) cell lines. The internalization of the particles by MNT-1 cells and their 3D localization in a fixed configuration are addressed through 2D optical images acquired in different planes along with the cell culture depth. 2D hyperspectral imaging is used to unequivocally identify the nuclei and the nanoparticles. The results indicate that the particles are distributed in distinct planes deep in the cell volume in the cytoplasmic and perinuclear regions. Furthermore, the emission signature of the nanoparticles enabled the determination of the intracellular temperature.

Functionalized Lanthanide Oxide Nanoparticles for Tumor Targeting, Medical Imaging, and Therapy.

Recent progress in functionalized lanthanide oxide (Ln2O3) nanoparticles for tumor targeting, medical imaging, and therapy is reviewed. Among the medical imaging techniques, magnetic resonance imaging (MRI) is an important noninvasive imaging tool for tumor diagnosis due to its high spatial resolution and excellent imaging contrast, especially when contrast agents are used. However, commercially available low-molecular-weight MRI contrast agents exhibit several shortcomings, such as nonspecificity for the tissue of interest and rapid excretion in vivo. Recently, nanoparticle-based MRI contrast agents have become a hot research topic in biomedical imaging due to their high performance, easy surface functionalization, and low toxicity. Among them, functionalized Ln2O3 nanoparticles are applicable as MRI contrast agents for tumor-targeting and nontumor-targeting imaging and image-guided tumor therapy. Primarily, Gd2O3 nanoparticles have been intensively investigated as tumor-targeting T1 MRI contrast agents. T2 MRI is also possible due to the appreciable paramagnetic moments of Ln2O3 nanoparticles (Ln = Dy, Ho, and Tb) at room temperature arising from the nonzero orbital motion of 4f electrons. In addition, Ln2O3 nanoparticles are eligible as X-ray computed tomography contrast agents because of their high X-ray attenuation power. Since nanoparticle toxicity is of great concern, recent toxicity studies on Ln2O3 nanoparticles are also discussed.

Synthesis, characterization and effect of dopant on magnetic hyperthermic efficacy of Gd2O3 nanoparticles

Rare-earth oxides are paramagnetic materials and their high magnetic susceptibility in the bulk makes them potentially promising materials, but the magnetic properties of their nanoparticles remain incompletely characterized. We explore the effect of dopant (Tb3+ and Eu3+) in Gd2O3 host lattice as a heating agent for magnetic hyperthermia application. The structural, optical, and magnetic properties of the pristine, Gd2O3:Tb3+ and Gd2O3:Eu3+ nanocrystals were studied by XRD, HR-TEM, FTIR, and VSM. XRD analysis revealed the presence of mixed-phase (cubic and monoclinic) in pristine, and doped Gd2O3 nanoparticles. The morphological information has been observed with the help of HRTEM and the calculated inter-planar spacing is in well agreement with JCPDS data. Particles are nearly spherical and diameter ∼15 nm, estimated from HRTEM image. FTIR spectroscopic analysis confirms the presence of Gd-O-Gd stretching at 583cm−1. We confirmed the paramagnetic nature for all samples using VSM analysis. The self-heating capability of prepared samples are investigated by performing the induction heating experiment and it is assessed through calculated SAR and ILP values with help of Box-Lucas fitting model where 10% Tb3+ doped Gd2O3 has maximum values.

Plastic Scintillators and Radiation Detectors Based on Triphenyl Pyrazoline Derivatives

AbstractPlastic scintillators (PS) allow design of portative lightweight devices for quantification of low‐activity radiation sources. We have recently suggested a new type of organic fluorophores based on triphenyl pyrazoline (PZ) derivatives with high fluorescence quantum yield showing high radioluminescence when combined with a polyvinyltoluene (PVT) matrix. In this publication we report on radioluminescence properties of the PZ−X family with various halogen substitution (X=F, Cl, Br, I), or having vinyl functional group (vPZ, X=vinyl). PS based on such fluorophores and PVT matrix can be prepared as bulk samples, micrometer size beads or cladding on optical fibers. Application of fluorophores with vinyl functional groups enabled their enhanced interaction with the matrix due to covalent bonding between the components. We demonstrate high performance of PZ−X fluorophores and especially vPZ fluorophore in fabrication of nanocomposites for detection of various types of radiation. Scintillators have enhanced gamma ray detection capabilities with an addition of triphenyl Bi, or Gd2O3 nanoparticles. High fluorescence quantum yield and luminosity of PZ fluorophores allows dramatical reduction of their content in PS systems. Mechanisms of energy transfer and conversion during scintillation process are discussed. Special consideration is given to enhancement of α/β and neutron/gamma (n/γ) pulse shape discrimination (PSD) function of the developed scintillators.