Yb2O3 Nanoparticles Research Articles

Preparation and properties of Mg-Nd binary alloy MAO/SiO2@α-Fe2O3 organic composite coating

In order to make magnesium alloys better used in aviation, electronic information and other fields, it is necessary to improve their corrosion resistance and wave absorption properties. In this paper, a composite coating with corrosion resistance and wave absorption properties was prepared on magnesium alloy by micro-arc oxidation-organic coating technology. An organic absorbing coating with a thickness of about 40 μm was sprayed on the MAO coating containing Yb2O3 nanoparticles. Among them, the absorbing fillers in the organic coating are mainly SiO2 and α-Fe2O3. Three different mass ratios of SiO2 and α-Fe2O3 were set to 20%, 22.5% and 25%, respectively, to prepare three different MAO/SiO2@α-Fe2O3 organic composite coatings. The morphology, roughness, microstructure and chemical composition of the organic composite coating are characterized. The results show that after coating the organic composite coating, the roughness of the coating is significantly reduced, and the compactness and interlayer adhesion of the coating are significantly improved. The electrochemical test and SKPFM test of the organic composite coating were carried out. The results showed that with the increase of the mass ratio of SiO2 and α-Fe2O3, the corrosion resistance and stability of the organic composite coating increased, and the Volta potential also gradually moved up. The microwave absorbing properties of organic composite coatings were studied by vector network analyzer. The results show that the microwave absorbing properties of the coatings are positively correlated with the mass ratio of SiO2 and α-Fe2O3.

INFLUENCE OF MODIFICATION ON PROPERTIES OF ZSM-5 ZEOLITE IN THE REACTION OF TOLUENE ALKYLATION WITH ISOPROPANOL

Bimetallic catalysts based on ZSM-5 zeolite modified with ytterbium and nickel have been prepared. The influence of the concentration of ytterbium (1.7–5.0 wt.%) and nickel (1.0–1.5 wt.%) on the acidic, textural and catalytic properties of the zeolite in the reaction of alkylation of toluene with isopropanol in the temperature range of 300–3500C was studied. It has been shown that the unmodified zeolite HZSM-5 exhibits low selectivity (54.6–58.2%) for isopropyltoluenes (3-IPT, 4-IPT, and 2-IPT) than the modified catalysts. In addition, the content of the valuable 4-IPT isomer does not exceed 44.2%. Modification of HZSM-5 with ytterbium in an amount of 5.0 wt.% leads to an increase in the selectivity for isopropyltoluenes up to 68.7%, and the selectivity for 4-IPT up to 68.8%. Additional modification of the 3%-Yb-HZSM-5 catalyst with nickel in the amount of 1.0 wt.% prevents the formation of 2-IPT and promotes an increase in the yield of 4-IPT. The modified catalysts were characterized by XPA, BET, BJH, and ammonia TPD. Modification, calcination, and successive treatment of the catalyst with air and hydrogen leads to a dispersed distribution of Yb2O3 and metallic nickel oxide nanoparticles in the outer surface and in the pores of the zeolite, which causes a decrease in the specific surface area, total pore volume, and an increase in the fraction of mesopore volume. As a result of the interaction of modifiers with acidic OH groups of the zeolite, the concentration of strong Brønsted acid sites decreases and new, stronger Lewis acid sites form. All this has a decisive effect on the selectivity of 4-IPT formation and the stability of the bimetallic catalyst. The maximum selectivity for 4-IPT on a 3% Yb 1.0% Ni/HZSM-5 bimetallic catalyst is achieved at 3300C and is 71.5% at a toluene conversion of 24.6%.

Effect of Yb2O3@C composite catalyst on hydrogen storage performance of Mg–La–Ni alloy

The present study successfully synthesized a Yb2O3@C composite catalyst using an enhanced chemical blow molding carbonization method. The characterization results showed that the catalyst was highly dispersed in the porous carbon matrix by Yb2O3 nanoparticles. And the catalyst has developed pore structure, high specific surface area and high defect density. Yb2O3@C was mixed with the Mg96La3Ni alloy through ball milling, and the impact of varying amounts of Yb2O3@C on the hydrogen storage performance of Mg96La3Ni was comprehensively investigated. The research findings indicate that the addition of Yb2O3@C notably refines the Mg-based alloy, leading to an increase in both specific surface area and the count of active sites. Furthermore, Yb2O3@C markedly enhances the hydrogen sorption kinetics of Mg96La3Ni, with the most substantial impact noted at a Yb2O3@C content of 3 wt %. Additionally, the incorporation of Yb2O3@C substantially decreases the dehydrogenation activation energy of the alloy, while leaving its thermodynamic properties unaffected. Yb2O3 nanoparticles and the carbon matrix work synergistically to promote both nucleation reactions and hydrogen diffusion. This study presents a novel strategy for enhancing the performance of hydrogen storage materials based on magnesium.

Multimotion of Marangoni Propulsion Ships Controlled by Two-Wavelength Near-Infrared Light.

Multimode motion of Marangoni propulsion ships on a water surface as per a near-infrared, two-wavelength selective response is achieved for the first time. The ships are rhombus- or propeller-shaped polyacrylamide or siloxane resin-based gels in which Nd2O3 and Yb2O3 nanoparticles are incorporated separately for photothermal conversion at 808 and 980 nm, respectively. The rhombus geometry is for straight locomotion, and the propeller geometry is for rotation. On/off remote control of the forward and backward locomotion of a rhombus-shaped ship and of the clockwise and counterclockwise rotations of a propeller-shaped ship via irradiation with 808 or 980 nm near-infrared light is demonstrated. The nanoparticles are incorporated into the desired locations of the gels, enabling selective local heating of the gels without focusing the light. The temperature gradient of the ships by local heating, based on a photothermal conversion, generates a Marangoni propulsion force to move the ship in the desired direction.

Production and Characterization of RE<sup>3+</sup>:Yb<sub>2</sub>O<sub>3 </sub> Nanoparticles

In this study, doped ytterbium oxide (Yb2O3) nanoparticles (NPs) with different dopant type (Eu and / or Tb) and undoped were synthesized by wet chemical method using nitrate salt as a starting source. Afterwards, they were calcined at 900 °C for 4 h. The crystal structure phase, size, and morphology of undoped and doped Yb2O3 nanoparticles (NPs) were characterized by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Undoped and doped NPs were exhibited cubic bixbyite-type crystal structure (Ia-3 space group). Lattice parameter changes caused by dopant element in NPs were examined using X-ray peak profile analysis. In order to investigate the occuring changes in the crystal structure, average crystallite size (CS) and lattice parameter (LP) values were computed with Williamson–Hall (W–H) and Cohen-Wagner (C–W) methods, respectively. It was observed that the crystal structure of the doped NPs expanded compared to the undoped Yb2O3 NPs, which explains the increase in the LP and CS values. The LP values of all the NPs were ranged from 10.444 Å (R2 = 94.9) to 10.453 Å (R2 = 81.8) while the CS of them were between 19 nm (R2 = 95.9) and 24 nm (R2 = 88.8). All the NPs exhibited nearly spherical and agglomerate structure and there were also few pores between the agglomerate particles in the structure. Besides, continuous agglomerate morphology formation was observed in particles containing Tb. The average nanoparticle size values were varied between 46 and 115 nm depending on the dopant element.

Modelling of relation between synthesis parameters and average crystallite size of Yb2O3 nanoparticles using Box-Behnken design

A straightforward wet chemical method has been applied for the fabrication of Yb2O3 nanoparticles (NPs) from ytterbium nitrate solution by using ammonium carbonate as precipitation agent. Effects of precursor molarity (0.1, 0.15 and 0.2 M), calcination temperature (800, 900 and 1000 °C) and time (2, 4 and 6 h) on average crystallite size (CS) of the NPs were statistically investigated by using Box-Behnken design. A simple and effective quadratic model was proposed for controlling the CS. The CS values were calculated by using Williamson Hall method (W-H) from X-Ray Diffraction (XRD) broadening data and found to be ranging between 13 and 26 nm. Agglomerated NPs morphologies and particle sizes were revealed by Field Emission Gun-Scanning Electron Microscopy (FEG-SEM). Fourier Transform Infrared (FTIR) spectrophotometry confirmed that as-received Yb2(CO3)3xH2O powders were successfully transformed into Yb2O3 NPs with calcination. High-Resolution Transmission Electron Microscopy (HRTEM) results verified the average CS values. ANOVA analyses revealed that linear and squared terms of the production parameters were significantly related to the CS whereas interaction terms were insignificant with the confidence level of 95% (R2 = 92.67%, R2-adj = 87.17%). The calcination temperature had the highest impact on the average CS followed by the time and precursor molarity. Increasing calcination parameters resulted in bigger crystallites whereas increasing precursor molarity exhibited a critical supersaturation value (0.15 M) from which the average CS was decreased.

Modulating physicochemical properties in Gd3+@Yb2O3 nanospheres for efficient electrochemical monitoring of H2O2.

Herein, a uniform spherical shaped Gd(III) doped Yb2O3 (Gd@Yb2O3) nanoparticles (NPs) was successfully synthesized via hydrothermal method for electrochemical detection of H2O2. The calcination effect and porosity of the materials well elaborated in the present work. The optical properties, size, morphological, thermal, sensing, surface and crystalline properties of synthesized materials were examined by several techniques. The enhanced electrocatalytic performance of Gd@Yb2O3 make the present sensor excellent towards the determination of H2O2.The anodic and cathodic peak current increased regularly with addition of H2O2 solution. The electrode coating surface was stable even after a number of electrochemical cycles and have high limit of detection (51nM). Moreover, the present sensor was successfully employed for detection of H2O2 in real samples.

Assessing the potential application of bio-compatibly tuned nanosensor of Yb2O3 for selective detection of imazapyr in real samples

Imazapyr is one of the frequently employed herbicide for controlling the growth of broad range of terrestrial and perennial grasses grown along the crop fields. The excessive utilization of imazapyr has contaminated the water level at an alarming rate. So, there is an urgent need to develop a cheap, selective and sensitive sensor for the detection of imazapyr. Here, in this paper a novel bio-compatibly tuned fluorescent-nanosensor of APTES coated ytterbium oxide (Yb2O3) was fabricated under hydrothermal conditions. The surface modification with APTES has provided better control over the optical and luminescence properties of Yb2O3 nanoparticles and has been turned out as a contemporary approach for designing potential sensor for harmful toxins i.e. imazapyr. The higher biocompatibility and fluorescence properties have made Yb2O3 as one of the selective and sensitive material for the estimation of imazapyr. The quenching of fluorescence intensity for APTES coated Yb2O3 NPs was greatly magnified by increasing concentration of imazapyr and displayed a linear trend from 0−200 ppm with detection limit value of 0.2 ppm. The developed sensor has possessed excellent efficiency for sample collected from real field conditions and provided the wider scope in herbicide sensing.

Fabrication of Yb-doped TiO2 using liquid phase plasma process and its photocatalytic degradation activity of naproxen

Photocatalysts responding to visible light were prepared by doping ytterbium (Yb) to TiO2 powder by LPP method. Yb2O3 nanoparticles were uniformly precipitated on the surface of TiO2 powder, and when the precursor concentration was increased, the precipitated Yb2O3 nanoparticles increased. The precipitated Yb element lowered the band gap energy of Yb-doped TiO2 photocatalyst (YTP) by 0.07 to 0.14 eV compared to bare TiO2. YTPs degraded naproxen (NPX) better than bare TiO2, especially under blue LED light (maximum wavelength 470 nm), and YTP containing higher Yb elements showed higher decomposition activity. NPX was decomposed into CO2 and H2O by decarboxylation and demethylation by hydroxyl radicals generated from TiO2 photocatalysts, suggesting a degradation pathway based on the three intermediates detected by LC/MS analysis.

The role of Yb doped ZnO in the charge transfer process and stabilization

This work aims to investigate the role of Yb dopant in the ZnO photoactivity. A new material based on ZnO doped with a small amount of Yb (1% molar) has been synthesized, characterized and tested respect to an enhancement of the photoactivity via Electron Paramagnetic Resonance spectroscopy. The prepared material has been characterized via X Ray diffraction, UV visible spectroscopy and in particular with the transmission electron microscopy. The morphological analysis with high resolution TEM allowed us to identify the formation of a new species not visible with XRD and assigned to isolated Yb2O3 nanoparticles supported on the surface of larger particles of the more abundant zinc oxide phase. The as obtained material exhibits a band gap corresponding to UV light (≈3.3 eV), but nevertheless it shows a relevant photo-activity under irradiation with photons with λ > 420 nm (visible light). This phenomenon has been investigated by means of several methods. A specific EPR-based approach allowed to monitor and quantify the charge separation following the formation of holes in the valence band (VB) of the two materials.

Tuning of structural, optical and toxicological properties of Gd3+ doped Yb2O3 nanoparticles

Abstract The nanoparticles of Ytterbium oxide (Yb2O3) with spherical architectures have been synthesized by using hydrothermal procedure. The prepared Yb2O3 nanoparticles were further doped with Gd3+ ions for exploring the potential of the nanoparticles in terms of tuning the optical properties such as band gap. Here, we demonstrated that the dopant inside the nanoparticles affects the optical properties and show how it has a relevant consequence on the overall peak position of Yb2O3 as a function of dopant concentrations. We have also examined the crystallite changes in Yb2O3 nanoparticles by employing the X-ray peak profile analysis. The respective Williamson–Hall studies and size–strain plot were employed to study the individual roles of crystallite sizes and lattice strain over Yb2O3 nanoparticles as a function of Gd3+ ion doping. The factors including strain, stress and energy density value were computed for both bare and Gd3+ ion doped Yb2O3 nanoparticles. The toxicological profiling of bare and Gd3+ doped Yb2O3 nanoparticles were carried out by multiple assays including antibacterial, antifungal, seed germination assay and A. Cepa genotoxic studies. The results have demonstrated the excellent biocompatibility of prepared nanoparticles and signifying their potential applications in biomedical field.

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.

X-ray Attenuation Properties of Ultrasmall Yb2O3 Nanoparticles as a High-Performance CT Contrast Agent

Ultrasmall heavy metal-oxide nanoparticles can be utilized for highly enhancing contrasts in computed tomography (CT). In this study, ultrasmall Yb2O3 nanoparticles coated with biocompatible and hydrophilic D-glucuronic acid were for the first time prepared through a simple one-step polyol process, and their X-ray attenuation properties were investigated by measuring phantom images and X-ray attenuation powers. The average particle diameter of the nanoparticles was estimated to be 2.1 ± 0.1 nm by using transmission electron microscopy. The observed X-ray attenuation power was stronger than that of a commercial iodine CT contrast agent (i.e., Ultravist®) at the same atomic concentration and much stronger at the same number density, proving the potential of ultrasmall Yb2O3 nanoparticles for use as a powerful CT contrast agent.

Improving sulfur tolerance of Ni-YSZ anodes of solid oxide fuel cells by optimization of microstructure and operating conditions

In this study, we propose an improvement in the sulfur tolerance of nickel-yttria stabilized zirconia (Ni-YSZ) anodes for solid oxide fuel cells (SOFCs) by simultaneously employing optimized operating conditions and microstructural modifications. An electrolyte supported SOFC is operated at 20 ppm H2S impurity at 750 °C for 20 h degradation and 10 h recovery test. The current cycles with a higher amplitude and small pulse time during the constant current operation are beneficial for the mitigation of sulfur poisoning. The effect of humidity on the sulfur degradation of Ni-YSZ anode is also studied. The synergetic effect of microstructure modification and current cycling conditions improves the sulfur tolerance of Ni-YSZ anode. It has been found that, when an anode with a modified microstructure by infiltrated CeO2 and Yb2O3 nanoparticles is operated on 20 ppm H2S poisoned gas at 10% relative humidity and the optimum pulsed current cycling conditions, about 7 times less degradation of the SOFC performance is observed. This study shows that at lower H2S concentration, a stable operation of a SOFC with minimum degradation can be achieved with the combination of optimization of operating conditions and modification of the anode microstructure.

Long term determination of dopamine and uric acid in the presence of ascorbic acid using ytterbia/reduced graphene oxide nanocomposite prepared through a sonochemical route

Decoration of reduced graphene oxide (RGO) with nano-size inorganic particles creates a class of composites with considerably improved characteristics. Improvements in the function of electrochemical energy-storage devices, catalysts and sensors using such particles, have hence attracted a great deal of interest to the area. This manuscript tends to report the results of the research on the application of a sonochemical route for anchoring nano-sized Yb2O3 (Ytterbia) particles, on sheets of RGO. The anchoring phenomenon is based on the self-assembly of the Yb2O3 nano-particles under sonochemical treatments in an ultrasonic bath. To evaluate the method, the produced Yb2O3-RGO nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), which proved the uniform distribution of the nano-particles on the RGO sheets. Additionally, the Yb2O3-RGO nano-composites were evaluated through cyclic voltammetry (CV), to assess the potentials of their application in electrochemical devices. The high activity of the produced Yb2O3-RGO nanocomposites can be attributed to the synergistic effect between Yb2O3 and RGO as well as the porous structure of the nanocomposite. Due to their stability, electrocatalytic properties and large accessible surface area, the low detection limit sensor is usable for long term usages in blood serum and wide linear dynamic range. There are linear relationships between current intensities and concentrations in the region 0.3–800μM dopamine (DA), and 0.2–210μM uric acid (UA), and the limits of detection (LOD) (S/N=3) are down to 0.02μM and 0.01μM for DA and UA, respectively in 0.5mM solution of ascorbic acid.

An enhanced electrochemiluminescence sensor modified with a Ru(bpy)32 +/Yb2O3 nanoparticle/nafion composite for the analysis of methadone samples

The sensitive interaction between Ru(bpy)32+ and methadone was used for the modification of a solid-state electrochemiluminescence electrode, and it was also successfully applied to determine methadone in the samples. The working electrode was made of a Yb2O3−containing modified carbon paste electrode. The presence of Yb2O3 nanoparticles in the structure of the electrode, was found to enhance its sensitizing effect towards the Ru(bpy)32+-methadone electrochemiluminescence system. The electrodes with the optimal make-up revealed a linear ECL-concentration behavior from 5×10−9–3×10−7M and reached method detection limit as low as 2.1×10−10M with a relative standard deviation of 4.4% (S/N=3). This modified ECL could present a simple yet sensitive and selective route for the determination of methadone in different samples.

Emission behaviors of Yb2O3 nanoparticles pumped by 980nm laser at different power densities

Abstract Yb2O3 nanoparticles synthesized via Pechini type sol-gel method were characterized by TEM, SAED, EDS, XRD, SEM and Raman spectrometer. Their emission properties were recorded by a fluorescence spectrophotometer with a 980 nm laser as the excitation source. These spectral results indicate that there are two optical bistable emissions at low/high laser power densities, i.e. Yb3+–Yb3+ dimer cooperative upconversion luminescence and thermal emission. Thus, Yb2O3 nanoparticles might be regarded as a candidate for intrinsic optical bistability.

Preparation, Growth, and Magnetic Properties of Co-doped Yb2O3 Nanoparticles and Thin Films by the Sol–Gel Process

In this study, the preparation, growth, structure and magnetic properties of Co-doped Yb2O3 (with the Co concentration of x=0.2) nanoparticles and thin films are studied. Precursor solutions were prepared by using the sol–gel synthesis process to produce nanoparticles and thin films. Co-doped Yb2O3 thin films with different thickness were produced on Si(100) substrate using the sol–gel dip coating procedure. The particle size and the crystal structure of nanoparticles were ascertained by X-ray diffraction and Scanning Electron Microscope. The surface morphologies and the microstructure of all samples were investigated by means of the Scanning Electron Microscope and the X-ray diffraction. A Quantum Design PPMS was used for magnetic measurements. Surface morphologies of Co-doped Yb2O3 thin films were found to be dense, without porosity, uniform, and devoid of cracks and pinholes. The grain size and thin-film thickness of Co-doped Yb2O3 were determined to be approximately 50 nm and 84 nm, respectively.

Corona charging of aerosols for electrogasdynamic generators : P. J. MUSGROVE and A. D. WILSON, Department of Applied Physical Sciences, Reading University, Reading, England. Energy Conversion12, 21–24 (1972)

Decoration of reduced graphene oxide (RGO) with nano-size inorganic particles creates a class of composites with considerably improved characteristics. Improvements in the function of electrochemical energy-storage devices, catalysts and sensors using such particles, have hence attracted a great deal of interest to the area. This manuscript tends to report the results of the research on the application of a sonochemical route for anchoring nano-sized Yb2O3 (Ytterbia) particles, on sheets of RGO. The anchoring phenomenon is based on the self-assembly of the Yb2O3 nano-particles under sonochemical treatments in an ultrasonic bath. To evaluate the method, the produced Yb2O3-RGO nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and field-emission scanning electron microscopy (FE-SEM), which proved the uniform distribution of the nano-particles on the RGO sheets. Additionally, the Yb2O3-RGO nano-composites were evaluated through cyclic voltammetry (CV), to assess the potentials of their application in electrochemical devices. The high activity of the produced Yb2O3-RGO nanocomposites can be attributed to the synergistic effect between Yb2O3 and RGO as well as the porous structure of the nanocomposite. Due to their stability, electrocatalytic properties and large accessible surface area, the low detection limit sensor is usable for long term usages in blood serum and wide linear dynamic range. There are linear relationships between current intensities and concentrations in the region 0.3–800 μM dopamine (DA), and 0.2–210 μM uric acid (UA), and the limits of detection (LOD) (S/N = 3) are down to 0.02 μM and 0.01 μM for DA and UA, respectively in 0.5 mM solution of ascorbic acid.