Neodymium Hydroxide Research Articles

(Nanocarbons Division Poster Award, 1st Place) Nd2O3 Templated Carbon Nanostructures for Energy Storage

Increased energy consumption has triggered the development of various energy storage devices. Supercapacitors have gained attention as energy storage devices due to their high-power density and long cycle life. The energy density of supercapacitor can be increased by combining electric double layer capacitance (EDLC) and pseudocapacitance (PC). A hybrid material based on rare-earth metal oxide templated carbon will be presented that combines both EDLC and PC within the same material. Specifically, neodymium hydroxide (Nd(OH)3) reacted with acetylene and steam to form carbon coated Nd2O3. Both Nd(OH)3 nanorods and nanospheres were used to prepared templated carbon followed by partial or complete washing of metal oxide. The resulting carbon exhibit the surface area of 1245 m2/g. Asymmetric coin cell was constructed with capacitance of 180.5 F/g and energy density of 76.8 Wh/kg This work paves the door to develop novel hybrid supercapacitors.

Voltammetric immunoassay based on MWCNTs@Nd(OH)3-BSA-antibody platform for sensitive BSA detection

Anelectrochemical approach is presentedbased on multiwall carbon nanotubes (MWCNTs) and neodymium(III) hydroxide (Nd(OH)3) nanoflakes for detection of bovine serum albumin (BSA). The materials were characterized morphologically (XRPD, SEM, and HR-TEM) and electrochemically (DPV, EIS). The MWCNTs@Nd(OH)3 composite was used as support for bovine serum albumin polyclonal antibody (anti-BSA). After the antibody immobilization on the electrochemical platform and antigen/antibody binding time (optimum 60min), the proposed approach shows a linear voltammetric response toward BSA concentration in the range 0.066 to 6.010ngmL-1 at maximum peak potential of 0.13V (vs. Ag/AgCl). Limit of detection (LOD) and limit of quantification (LOQ) were 18pgmL-1 and 61pgmL-1, respectively. The precision of the method calculated as relative standard deviation (RSD) of five independent measurements was better 3%. The selectivity of the optimized method regarding structurally similar proteins (human serum albumin and human hemoglobin), ions (Na+, K+, Ca2+, and NO2-), or compounds (glucose, ascorbic acid, dopamine, uric acid, paracetamol, and glycine) was found to be satisfactory, with the current changes of less than 5% in the presence of up to 1 × 105 times higher concentrations (depending on the compound) of the listed potentialinterfering compounds. Practical applicability of immunosensor for BSA determination in cow whey sample, with recovery values in the range 97 to 103%, shows that the developed method has highpotential for precise and accurate detection of BSA, as well as exceptional miniaturization possibilities for on-site and equipment-free sensing.

Recycling rare earth from ultrafine NdFeB waste by capturing fluorine ions in wastewater and preparing them into nano-scale neodynium oxyfluoride

Ultrafine NdFeB waste is a relatively clean waste produced during NdFeB magnet processing. Fluorine-containing wastewater is a common type of industrial wastewater, such as stainless steel pickling wastewater. In this work, rare earth element neodynium was recycled from ultrafine NdFeB waste by capturing fluorine ions in the fluorine-containing wastewater and prepared into neodynium oxyfluoride. The reaction process was investigated through UV-Vis-NIR, thermogravimetry/differential thermogravimetry (TG/DTG), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The neodymium hydroxide in the ultrafine NdFeB waste reacted with fluorine ions to form Nd(OH)2F, and Nd(OH)2F was then transformed into neodymium oxyfluoride after decomposition. The formed neodymium oxyfluoride is found to be particles with rhombohedral structure and a particle size of around 50 nm. The reaction kinetics of forming Nd(OH)2F was investigated. The reaction kinetic equation was established and the reaction activation energy was calculated. The effect of fluorine ion concentration on the reaction rate and products was evaluated. The results show that the reaction rate increases with the increase of fluorine ion concentration in the range of 0.01–1.5 mol/L, but it has little effect. In addition, the fluorine ion concentration affects the crystallinity of formed neodymium oxyfluoride. The recycling process not only realizes the sustainable utilization of rare earths, but also reduces the concentration of fluorine ions in the fluorine-containing wastewater, achieving two goals with one stone.

Influence of the amount of intermetallics on the degradation of Mg-Nd alloys under physiological conditions

The influence of amount of intermetallics on the degradation of as-extruded Mg-Nd alloys with different contents of Nd was investigated via immersion testing in DMEM+10% FBS under cell culture conditions and subsequent microstructural characterizations. It is found that the presence of intermetallic particles Mg41Nd5 affects the corrosion of Mg-Nd alloys in two conflicting ways. One is their negative role that their existence enhances the micro-galvanic corrosion. Another is their positive role. Their existence favours the formation of a continuous and compact corrosion layer. At the early stage of immersion, their negative role predominated. The degradation rate of Mg-Nd alloys monotonously increases with increasing the amount of intermetallics. Mg-5Nd alloy with maximum amount of intermetallics suffered from the most severe corrosion. With the immersion proceeding (≥7 days), then the positive role of these intermetallic particles Mg41Nd5 could not be neglected. Owing to the interaction between their positive and negative roles, at the later stage of immersion the corrosion rate of Mg-Nd alloys first increases with increasing the content of Nd, then reaches to the maximum at 2 wt. % Nd. With a further increase of Nd content, a decrease in corrosion rate occurs. The main corrosion products on the surfaces of Mg-Nd alloys include carbonates, calcium-phosphate, neodymium oxide and/or neodymium hydroxide. They are amorphous at the early stage of immersion. With the immersion proceeding, they are transformed to crystalline. The existence of undegradable Mg41Nd5 particles in the corrosion layer can enhance the crystallization of such amorphous corrosion products.

Preparation and characterization of neodymium hydroxide powder via the hydration method

The preparation of Nd(OH) 3 powder by the direct hydration method using Nd 2 O 3 as a raw material was studied, and the effects of stirring mode, H 2 O and Nd 2 O 3 molar ratio, stirring rate, and reaction time on temperature change and conversion rate in a hydration system were analyzed. The reasonable process conditions for the direct hydration of Nd(OH) 3 by Nd 2 O 3 were then determined. Process, morphology, and structure were considered in the preparation of neodymium hydroxide powder, and its composition was investigated by X-ray powder diffraction, scanning electron microscopy, laser particle size analysis, thermogravimetric differential thermal analysis, and chemical analysis. It has been proved that the process is simple and feasible, in line with the concept of modern green chemistry, and the products also meet the market requirements. The hydration method is that Nd 2 O 3 and H 2 O are directly mixed in the heat insulation reactor that is an environmentally friendly method for the preparation of neodymium hydroxide. Experiments show that this method is feasible in industry which involves a short process and takes into account the cost and energy savings. The particle size of the product is small (629 nm) and the dispersion of the product is good.

Optically active neodymium hydroxide surface-functionalized mesoporous silica micro-cocoons for biomedical applications

Neodymium hydroxide (Nd(OH)3)-surface modified mesoporous silica micro-cocoon microstructures were prepared using a facile single-step sol-gel chemical process. XRD revealed the semi-crystalline nature of the as-prepared materials. TEM and SEM micrographs exhibited highly monodisperse, non-aggregated, typical ordered mesoporous, and irregular sized cocoon-shaped micro-structures with a narrow size distribution. Optical properties, that were examined in the aqueous media, revealed a high colloidal stability and the formation of a semi-transparent colloidal solution. The colloidal solution of Nd(OH)3-surface functionalized micro-structures revealed well characteristics absorption bands of Nd3+ ions in the visible region. thus validating the successful coating of SiO2@Nd(OH)3 layer over the surface silica forming core-shell structures. Zeta potential, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) bromide, and neutral red uptake assays were applied in a dose-dependent manner to investigate the biocompatibility and toxic potential of the designed cocoon-shaped microstructures. Both the assays and the high zeta potential value demonstrated good cell viability even at high concentrations and hydrophilic conditions, indicating excellent biocompatibility and non-toxicity. These highly hydrophilic, optically active, mesoporous, biocompatible, and non-toxic cocoon-shaped microstructures could be potentially suitable candidates for optical bio-probes and drug delivery applications.

Synthesis and characterization of Nd(OH)3-ZnO composites for application in photocatalysis and disinfection

Nd(OH)3-ZnO composites were synthesized with three content of Neodymium (1, 3 and 5 wt%) and characterized in terms of their structural, morphological, vibrational, optical, surface, photocatalytic and antimicrobial properties. The Nd(OH)3-ZnO composites are constituted by ZnO, which showed hexagonal structure, three-dimensional morphology analogous to an arrangement of flowers with hexagonal rods, and the Nd(OH)3 in the hexagonal phase with irregularly spherical shape. The presence of the Nd(OH)3 in the composites promoted some structural degree of disorder in the ZnO network as well as interstitial defects and oxygen vacancy, which improved photocatalytic and antimicrobial activity. From the Box-Behnken design and response surface methodology, it was determined that the 1Nd(OH)3-ZnO composite showed the highest photocatalytic activity, which was attributed to its higher crystallinity, smaller crystallite size and particle width, band gap energy close to ZnO and lower recombination rate compared to ZnO. Nd(OH)3-ZnO composites showed higher antimicrobial activity against E. coli and S. aureus than ZnO pure, evidencing the synergistic effect between Nd(OH)3 and ZnO in the composites. Therefore, this study highlights the synthesis of Nd(OH)3-ZnO composites combining zinc oxide and neodymium hydroxide with excellent photocatalytic and antimicrobial activity, which can be used in different practical applications such as luminescent material, photocatalyst and antimicrobial agent.

Separation of Cerium from Neodymium Hydroxide Concentrate Through Decomposition and Leaching Using HNO3

The thermal decomposition or calcination of neodymium hydroxide concentrate product by pilot plant of REOH into CeO2, La2O3 and Nd hydroxide concentrate in Center for Accelerator Science and Technology has been performed. From the result of start-up and validation was obtained neodymium hydroxide concentrate which still containing of impurities especially Ce. The purpose of this research to separate Ce from Nd(OH)3 concentrate by thermal decomposition to form Nd oxide (Nd2O3). Calcination temperature was 1000°C, and variation of time. The result of calcination were dissolved using aqueous HNO3 with molarity variation and the level of leaching was five times. From the results, it can be stated that calcination could convert Nd(OH)3 concentrate to Nd2O3 concentrate. Cerium hydroxide was easy dissolve in aqueous HNO3 while CeO2 couldn’t. The longer of calcination time, the formed of Nd2O3 is more perfect. The results of 3 hours calcination for the %weight of La increase until 12,50%, Ce increase to 10,42% and Nd increase to 52,08%. The composition of La in solid of leaching products use 1 M HNO3 with five leaching times is 3,57%, while Ce is 50.26% and Nd is 0.36%. The kinetic calcination and leaching followed reaction control.

A Facile Chemical Precipitation Method for the Synthesis of Nd(OH)3 and La(OH)3 Nanopowders and their Supercapacitor Performances

AbstractA facile chemical precipitation method is used to prepare both lanthanum hydroxide [La(OH)3] and neodymium hydroxide [Nd(OH)3] nanopowders in an ambient temperature without the addition of any surfactants. Both rare‐earth hydroxides nanopowders are characterized by X‐ray diffraction and FE‐SEM analysis. The supercapacitor performances of La(OH)3 and Nd(OH)3 electrodes are studied by cyclic voltammetry, electrochemical AC‐impedance and galvanostatic charge‐discharge studies. It revealed that Nd(OH)3 electrode possesses a high specific capacitance (Csp) than La(OH)3 electrode. Hence, an asymmetric supercapacitor device is fabricated and denoted as Nd(OH)3||AC in 6 M KOH as the electrolyte soaked in the electrospun poly(vinylidene fluoride) membrane as the separator, which exhibited an energy density of 18.8 Wh kg−1 at a power density of 796 W kg−1.

Preparation and characterization of polystyrene/neodymium hydroxide (PS/Nd(OH)3) nano-composites

Composites of polystyrene and Neodymium hydroxide nanrods (PS/Nd(OH)3) were formulated and characterized in this study. Cetyl (1-hexadccyl) trimethyl ammonium bromide (CTAB) was used as dispersion agent for the Nd(OH)3 rods in the PS matrix. PS/Nd(OH)3 composites were prepared by solution and melt compounding. Morphological, thermal, and mechanical properties of the prepared composites were investigated. CTAB was found to be more effective as dispersion agent in composites prepared by solution compounding in comparison with those prepared by melt compounding, and that was due to the mild conditions used in solution compounding. Nonetheless, impact strength of the composite at 0.5 wt% Nd(OH)3 was drastically reduced in the absence of CTAB. Both tensile and impact strengths were found to greatly decreased at higher loading of Nd(OH)3, e.g. 5 wt%, even with the use of CTAB. Thermal stability of the PS/Nd(OH)3 composites was noticeably increased at relatively low loading of Nd(OH)3, e.g. 0.5 wt%.

Long-Term Experimental Determination of Solubilities of Micro-Crystalline Nd(III) Hydroxide in High Ionic Strength Solutions: Applications to Nuclear Waste Management

In this study, the experimental results from long-term solubility experiments up to 1146 days on micro-crystalline neodymium hydroxide, Nd(OH)3(micro-cr), in high ionic strength solutions at 298.15 K under well-constrained conditions, are presented. Hydrogen ion concentrations in our experiments are controlled by the dissolution of Nd(OH)3(micro-cr) without artificial adjustment with addition of either an acid or a base, preventing the possibility of phase change that could be induced especially by addition of a base. Such an experimental design also provides the information about the hydrogen ion concentrations buffered by the dissolution of Nd(OH)3, which is currently lacking. The solubility data produced in this work, applicable to geological repositories in high ionic strength environments, are compared with the solubilities of Am(OH)3(s) predicted by using the Waste Isolation Pilot Plant (WIPP) thermodynamic model. The predicted values for Am(OH)3(s) are in good agreement with the experimental values for Nd(OH)3(micro-cr) obtained in this work. Our experimental data indicate that the pHm (negative logarithm of hydrogen ion concentration on a molal scale) buffered by dissolution of Nd(OH)3(micro-cr) ranges from ~ 9.5 to ~ 9.9. As the equilibrium constant for amorphous neodymium hydroxide, Nd(OH)3(am), is useful for several fields, the equilibrium constant regarding the dissolution of Nd(OH)3(am) for the following reaction, $$ {\text{Nd}}\left( {\text{OH}} \right)_{3} \left( {\text{am}} \right) + 3{\text{H}}^{ + } = {\text{Nd}}^{3 + } + 3{\text{H}}_{2} {\text{O}}\left( {\text{l}} \right) $$ is also obtained by evaluating the experimental data in a wide range of ionic strengths from the literature by using the WIPP thermodynamic model. The $$ \log_{10} K_{{{\text{s}}0}}^{0} $$ at 298.15 K for the above reaction obtained in this work is 16.85 ± 0.20 (2σ), which is similar to, but slightly lower than, the values in the literature evaluated in the low ionic strength range. This value can be applied to amorphous americium hydroxide, Am(OH)3(am), using Nd(III) as an analog to Am(III).

Synthesis of Neodymium Hydroxide Nanoparticles with CTAB at Low Temperature

Synthesis of Neodymium Hydroxide Nanoparticles with CTAB at Low Temperature

Cause of gas emission during sintering of Nd–Fe–B magnets

The degassing of an Nd14.5Fe76.3Ti1.4Al1.1B6.7 alloy (at %) has been studied. The cause for the degassing of the Nd–Fe–B material during its sintering is shown to be hydrogen evolution. At 250–550°C, hydrogen escapes from the Nd2Fe14B phase; at higher temperatures (700–900°C), hydrogen evolution from a Nd-rich phase takes place. The cause for hydrogen evolution consists in the decomposition of the Nd(OH)3 neodymium hydroxide during fine milling. The decomposition of hydroxide results in the formation of the Nd2O3 neodymium oxide, which deteriorates the magnetic isolation of Nd2Fe14B-phase grains; this leads to an abrupt increase in the irreversible magnetization losses.

Novel Extraction Process Of Rare Earth Elements From NdFeB Powders Via Alkaline Treatment

Abstract The alkaline treatment of NdFeB powders in NaOH solution at various equivalent amounts of NaOH at 100°C was performed. The resultant powders were then leached in 0.5M H2SO4 solution at 25°C for 2 minutes. At 5 equivalents of NaOH, neodymium in NdFeB powders was partially transformed to neodymium hydroxide. The transformation of neodymium to neodymium hydroxide actually occurred at 10 equivalents of NaOH and was facilitated by increasing the equivalent of NaOH from 10 to 30. In addition, iron was partially transformed to magnetite during the alkaline treatment, which was also promoted at a higher equivalent of NaOH. The leaching yield of neodymium from alkaline-treated powders was increased with an increasing equivalent of NaOH up to 10; however, it slightly decreased with the equivalent NaOH of over 10. The leaching yield of iron was inversely proportional to that of rare earth elements. NdFeB powders treated at 10 equivalents of NaOH showed a maximum leaching yield of neodymium and dysprosium of 91.6% and 94.6%, respectively, and the lowest leaching yield of iron of 24.2%, resulting in the highest selective leaching efficiency of 69.4%.

Mössbauer study of treated Nd2Fe14B

Abstract The Nd2Fe14B cylindrical magnets were treated with water solutions of alkali, acid, and salt. Mössbauer spectroscopy was applied to study the composition and properties of the surface material of the treated magnets. It is shown that the main phase of the permanent Nd2Fe14B magnet partly decomposes. The released α-Nd at the grain boundaries interacts with water and forms neodymium hydroxide matrix, and the released Fe diffuses into it. The presence of Fe-Nd(OH)3 is reflected in the paramagnet doublet in the Mössbauer spectra of treated neodymium magnets.

Preparation of Nd2O3 nanorods in SDBS micelle system

Well-crystallized Nd2O3 nanorods were prepared in the aqueous solution containing neodymium nitrate, sodium hydroxide (dissolved in ethanol) and sodium dodecyl benzene sulfonate (SDBS). One dimensional nanorods of neodymium hydroxide were synthesized first, which was then placed at different temperatures (600 and 800 °C) in a calcar for 10 h to form Nd2O3 nanorods. The morphology and crystal structure of the products were investigated by X-ray diffraction, transmission electron microscopy, field emission transmission electron microscopy, Fourier transform infrared spectroscopy and fluorescence spectrometry. By using SDBS micelles as a template, this method manufactured uniform morphology of hexagonal one-dimensional neodymium oxide nanorods with a diameter ranging from 20 to 70 nm. The length of the nanorods increased with prolonged reaction time.

Neodymium(III) Hydroxide Coprecipitation-FAAS System for the Speciation of Chromium in Natural Waters

A new coprecipitation procedure is presented for the speciation of Cr(III) and Cr(VI) on neodymium(III) hydroxide precipitate. Chromium determination was performed by flame atomic absorption spectrometry. Total chromium was determined by application of the same procedure after reducing Cr(VI) to Cr(III). The concentration of Cr(VI) was calculated by the concentration difference between total Cr and Cr(III). The optimal parameters that affected the quantitative recoveries of Cr(III) were investigated. The influences of co-existing ions were controlled. The detection limit and preconcentration factor for Cr(III) were 2.1 mu g/L and 100, respectively. The method was applied to the speciation and determination of chromium in natural water samples.

Template-free synthesis of neodymium hydroxide nanorods by microwave-assisted hydrothermal process, and of neodymium oxide nanorods by thermal decomposition

Based on the 150°C and 1h microwave-assisted hydrothermal reaction of Nd(NO3)3 dissolved in deionized water with pH 10 adjusted by concentrated NH4OH solution, the phase and morphology of the product, characterized by XRD, SEM and TEM analyses, were specified as hexagonal Nd(OH)3 nanorods 50nm in diameter and 700nm long, growing along the [001] direction. TGA analysis showed the evaporation of adsorbed water and dehydration of Nd(OH)3 to synthesize the final pure Nd2O3 product. With 500°C and 2h calcination of the Nd(OH)3 self-template precursor, Nd2O3 nanorods were synthesized, retaining both the morphology and growth direction of the precursor.

Determination of Some Heavy Metals by Flame Atomic Absorption Spectrometry Before Coprecipitation with Neodymium Hydroxide

A procedure is described for the determination of trace amounts of Cd(II), Ni(II), Cu(II), Pb(II), Fe(III), Co(II), and Mn(II) that combines flame atomic absorption spectrometry with neodymium hydroxide coprecipitation. The influences of analytical parameters (amount of neodymium, pH of the model solutions, etc.) that affect quantitative recoveries of the analyte ions were investigated. The effects of concomitant ions were also examined. The detection limits for analytes were found in the range of 0.2-3.3 microg/L. The validation of the presented procedure was controlled by analysis of certified reference materials (National Institute of Standards and Technology 1570a spinach leaves and TMDA 54.4 fortified lake water). The applications of the procedure were performed by the analysis of water, food, and herbal plants from Turkey.

Controlled synthesis of Nd(OH) 3 and Nd 2O 3 nanoparticles by microemulsion method

Three morphological structures of neodymium hydroxide (Nd(OH) 3) nanoparticles, i.e. cube, sphere, and oval-like, have been synthesized in microemulsion systems. Calcination of the Nd(OH) 3 nanoparticles with different morphologies at 900 °C in air yields neodymium oxide (Nd 2O 3) nanoparticles with the same morphological structures as those of their Nd(OH) 3 precursors. The Nd(OH) 3 nanoparticles are characterized by DSC–TGA, XRD and TEM, and the Nd 2O 3 nanoparticles by XRD and TEM. The morphological structures of the Nd(OH) 3 and Nd 2O 3 nanoparticles are controlled via the variation of the molar ratio of H 2O to CTAB ( ω). Experimental results show that the stirring time has no effects on the morphological structures of the Nd(OH) 3 nanoparticles, but rather has a significant impact on the sizes of the Nd(OH) 3 nanoparticles under the same ω. Possible formation mechanisms of the morphological structure of Nd(OH) 3 are proposed and discussed.