Barium Nitrate Research Articles

Solution combustion synthesis of porous β-BaSO4 nanopowder using benzenesulfonyl methylimidazolium chloride as fuel and sulfonating agent

In this study, we are reporting, the use of ionic liquid ( [3, 4-dcbsmim] Cl ) as a fuel and also as a sulfonating agent for the synthesis of nano BaSO4 by solution combustion route with barium nitrate as oxidizer and water as a solvent. The as-prepared BaSO4 nanopowder is characterized by x-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) and the surface area of BaSO4 was measured by BET method. The Scherrer formula reveals that the crystallite size was found to be 11.6 nm, with orthorhombic crystal phase.

Structural and X-ray spectroscopy studies of Pb1-xBax(NO3)2 solid solutions

Pb0.75(3)Ba0.25(3)(NO3)2, Pb0.68(3)Ba0.32(3)(NO3)2, Ba0.58(3)Pb0.42(3)(NO3)2, Ba0.81(3)Pb0.19(3)(NO3)2 crystals were grown for the first time when studying the Pb(NO3)2–Ba(NO3)2–H2O system. The crystals were grown in water solution with different relation of Pb(NO3)2 and Ba(NO3)2. It was found that series of solid solutions were formed by interaction of simple Pb(NO3)2 and Ba(NO3)2 compounds with a slow increase of volume and cell parameters from pure lead nitrate to pure barium nitrate. The crystal structure of all obtained Pb1-xBax(NO3)2 crystals belong to a cubic space group Pa-3. In these structures, Pb and Ba cations have the same coordination number 12, but different ionic radii (1.49 and 1.61 Å, respectively), anionic group is an equilateral triangle with O–O–O angle of 60° and O–O bond lengths ranging from 2.1305(8) to 2.2585(7) Å. The Pb2+ ion has a lone pair of electrons that are likely to be stereochemically active in these solid solutions leading to a significant amount of local disorder which explains the spread in the lattice parameters. The Pb1-xBax(NO3)2 solid solutions were characterized by X-ray photoelectron spectroscopy (XPS) by measuring the binding energies of the core-levels of constituting atoms and the shapes of the valence band. The XPS measurements indicate that the substitution of Pb for Ba does not cause changes in the charge states of the atoms constituting the Pb1-xBax(NO3)2 crystals. Matching the XPS valence-band spectra and the X-ray emission O Kα bands on a common energy scale indicates that the principal contributions of O 2p states occur at the top of the valence band of the crystals under study with also their substantial input in the upper and central portions of the band.

Development of Methods for Growing LiIO3 and Ba(NO3)2 Crystals as Materials for Laser Frequency Converters

New methods for growing LiIO3 and Ba(NO3)2 crystals have been developed. Barium nitrate crystals up to 12 × 12 × 100 mm3 in size and lithium iodate crystals up to 120 × 120 × 200 mm3 in size of necessary optical quality are obtained. The influence of рН on the morphology of Ba(NO3)2 growth faces is investigated. The data on the morphology of the {111} and {$$\bar {1}\bar {1}\bar {1}$$} faces of crystals grown at different solution acidities are obtained by atomic force scanning microscopy. The possibility of fabricating optical elements from LiIO3 crystals of ~100 × 100 × 100 mm3 in size is shown.

Investigation of the Structure and Magnetic Properties of Co+2 –Ti+4 Substituted Barium Ferrite Powder Prepared by Sol – Gel Method

In this research, Hexagonal barium ferrites and Co+2-Ti+4 substituted barium hex ferrite particles are prepared by the Sol-gel method. The starting materials were appropriate amount of barium nitrate (Ba(NO3)2), Iron nitrate (Fe(NO3)3) and citric acid (C6H8O7.H2O) were dissolved into distilled water. When water evaporated, the mixture became viscous and finally formed a very viscous brown dried gel. the sample was calcenid at 950°C for 5 h at a rate of 150 °C/h. to obtain a ferrite powder. The XRD method, using CuKα radiation (wave length λ=0.15405 nm) was used for product identification and phase structure at room temperature. The surface morphology of the powder was examined by scanning electron microscope (SEM). The absorption vibrations of the prepared samples were performed by a Fourier transformed Infrared (FTIR) spectrometer from 4000 cm-1 to 400 cm-1. The magnetic properties for the prepared samples were obtained using a vibrating sample magnetometer.

Direct Determination of Lead in Sea Water by High-Resolution Atomic Absorption Spectroscopy Using a Mixed Modifier Barium Nitrate–Hydrofluoric Acid

A procedure is proposed for the direct determination of lead in sea water by electrothermal atomization high-resolution atomic absorption spectrometry. The effect of background interferences due to sea water matrix is eliminated using a mixed modifier barium nitrate–hydrofluoric acid. The optimum amount of the modifier matrix is 60 µg Ba (NO3)2 + 1.52 µg HF. The conditions of analysis are as follows: pyrolysis temperature 600°C, atomization temperature 1200°C. The limit of detection for the developed procedure is 0.0003 mg/L.

Influence of laser structuring and barium nitrate treatment on morphology and electrophysical characteristics of vertically aligned carbon nanotube arrays

The technology of structuring arrays of multilayer carbon nanotubes using pulsed laser radiation is presented. Arrays of two types nanotubes (long and short) with different morphologies were synthesized on a silicon substrate by the method of plasma enhanced chemical vapor deposition from the gas phase. Samples with arrays of nanotubes located strictly perpendicular to the silicon substrate were obtained using an ytterbium fiber laser (1064 nm) with a galvanometric scanner. Raman spectroscopy showed a decrease in the defectiveness of the carbon nanostructure of the tubes after laser irradiation. Liquid treatment with Ba(NO3)2 applied to the array with subsequent annealing resulted in sticking of the nanotubes at their tips. The formation of cellular structure from array of carbon nanotubes with a greater length after laser scanning of the sample was observed. Such arrays of nanotubes made it possible to increase the current of electron emission by more than two times at lower threshold voltage compared with the original arrays of nanotubes. The current density increased from 65 to 150 μA/cm2. Structured arrays of nanotubes can be used to create efficient emission cathodes, as well as sensors, solar cells and MEMS structures.

Applying BaTiO3-coated TiO2 core–shell nanoparticles films as scaffold layers to optimize interfaces for better-performing perovskite solar cells

In this paper, we replaced mesoporous TiO2 nanoparticles scaffold layers by BaTiO3-coated TiO2 core–shell nanoparticles films which obtained by treating pure mesoporous TiO2 layers with 1.0 wt% barium nitrate solution, successfully realized the aim of optimizing interfaces bonding at TiO2/CH3NH3PbI3. Ultrathin BaTiO3 shell layer can combine better with CH3NH3PbI3 layer so as to reduce the existence of carrier recombination centers. Moreover, better optical absorption and larger fill factor were obtained in this manner by the reason of larger CH3NH3PbI3 grain size and fewer crystal boundaries. Furthermore, photoluminescence spectra and electrochemical impedance spectroscopy verified that our core–shell scaffold material contributes to accelerate carrier separation and retard carrier recombination. As a result, average power conversion efficiency enhanced from 11.20 to 13.76% under ambient conditions, which realized almost a quarter improvement than the devices based on pure mesoporous TiO2 layers. Such results have a certain guiding effect on solving interface defects and carrier recombination.

Parametric stimulated Raman scattering in barium nitrate crystals

The spectra of multifrequency parametric stimulated Raman scattering in a barium nitrate single crystal is investigated. When this single crystal is excited by ultrashort (80 ps) YAG : Nd3+ laser pulses with a wavelength of 1064 nm, a frequency comb of eight anti-Stokes components is observed in the visible spectral range. The Raman satellites are due to the totally symmetric vibrational modes of barium nitrate single crystal. The frequencies of the corresponding Raman Stokes components in the IR range (from 1193 to 9662 nm) are calculated. The results of the study open the way to form an array of laser frequencies from the IR to green spectral range with a period of 1047 cm–1.

Synthesis and Properties of Calcium, Strontium, and Barium Uranates

Pure crystalline compounds MIIU3O10 · n H2O (MII = Ca, Sr) and BaU2O7 · 3 H2O were obtained by reactions of synthetic schoepite (UO3 · 2.25 H2O) with aqueous solutions of calcium, strontium, and barium nitrates under hydrothermal conditions at 200°C and pH 7‒8. Their structure, dehydration, and thermal decomposition were studied by chemical analysis, X-ray fluorescence spectrometry, X-ray powder diffraction, IR spectroscopy, and thermogravimetric analysis.

Solubility of Radium Nitrate in Nitric Acid Solutions

The solubility of radium nitrate in concentrated HNO3 solutions was determined. The radium nitrate solubility decreases from ∼1 × 10−3 to ∼2 × 10−5 M as the HNO3 concentration is increased from 13.5 to 22 M. The solubility of radium nitrate in the examined range of HNO3 concentrations is 3–6 times higher than the solubility of barium nitrate under similar conditions.

Raman Laser with a Singly Resonant Cavity: Theoretical Model and Experiment

A semiclassical theoretical model of a Raman laser possessing a cavity which is resonant at the Stokes wavelength and not resonant at the pump wavelength has been developed. The wave equations describing evolution of amplitudes of the pump and Stokes pulses in the Raman cavity have been derived. Results of the theoretical modeling have been analyzed for conditions of an experiment with the Raman laser on barium nitrate crystal under the nanosecond pulse pump. Numerically calculated energy characteristics of the Raman laser as well as space-time dynamics of the Stokes generation have been demonstrated to be in reasonable agreement with the experiment.

Development of a Matlab Code for Plane Wave Lens and its Validation by Autodyn-2D

Plane wave generator is normally composed of two explosives having dissimilar detonation velocity. It is used for directing the spherically outgoing shock wave front to a planar form. Plane wave generators are utilized to find material behavior under dynamic loading. This paper presents the shock arrival time for two plane wave generators by developed Matlab code and its comparison with Ansys Autodyn. The diameter of both plane wave generators is kept the same. One plane wave generator is composed of Octogen and Barium Nitrate and the other is composed of Octogen and Tri Nitro Toluene. Obtained results were surprisingly in agreement. Maximum and minimum obtained flatness for the plane wave were ±0.56 and ±0.08ms respectively within the whole diameter of the plane wave generator. The developed code can be utilized to find the profile of a plane wave generator, minimizing the time and cost many times.

Dissolution Rates of Barium Nitrate in Water and Weak Nitric Acid Solutions Under Stirred and Stagnant Conditions

Barium nitrate is one of the least soluble metal nitrate phases normally present in the nitric acid based highly active liquor, which will require removal from highly active storage tanks during post-operational clean-out of the Sellafield nuclear site. Laboratory experiments have been carried out to determine the dissolution rate of barium nitrate in water and weak acid solutions. The influence of agitation (solutions being stirred by a paddle at a rate of 0, 40 and 60 revolutions per minute (rpm)), dissolution temperature (20–40 °C), nitric acid concentration (0–1 mol·L−1) and additional solution nitrate {from Al(NO3)3} concentration (0–0.5 mol·L−1) were investigated. An inscribed central composite experimental design was used for each level of stirred agitation (including unstirred), which allowed non-linear trends and interactions among variables to be statistically determined without carrying out a full factorial experimental array. It was found that the dissolution rate was faster for higher temperature, lower nitric acid concentrations and lower nitrate concentrations. Comparing experiments under like conditions, the barium nitrate dissolution rates at an agitation rate of 40 rpm were on average 56% of those at 60 rpm, while the dissolution rate in the unstirred experiments were on average 0.8% of those at 60 rpm, i.e. two orders of magnitude lower. Hence, the transition from stagnant solution conditions with diffusion controlled transfer of solute from the solid interface to agitated solution conditions was found to be significant. Statistical analysis of the data allowed the derivation of a predictive dissolution rate equation.

Integrated spectral and spatial information extraction in Raman spectroscopy

Raman spectroscopy has been widely used to analyze various substances quantitatively. Conventional studies are primarily focused on the spectral characteristics of Raman scattering. The spatial distribution is always ignored, which can be used to observe the physical properties, such as the particle size. In this article, the spatial information has been extracted from the Raman spectra of barium nitrate, demonstrating that the evident spatial width broadening varied with the particle size. The numerical result shows that the spatial width has a better linear correlation with the particle size, while the Raman intensity has a poor linear correlation. The integrated spectral and spatial information extracted in Raman spectroscopy has a potential application in the quantitative analysis of physical properties.

Cationic Dependence of X-ray Induced Damage in Strontium and Barium Nitrate.

The response of solids to X-ray irradiation is not well understood in part because the interactions between X-rays and molecules in solids depend on the intra- and/or intermolecular electronic properties of the material. Our previous work demonstrated that X-ray induced damage of certain ionic salts depends on the irradiating photon energy, especially when irradiated with photons of energy near the cation's K-edge. To advance understanding of the cationic dependence of X-ray photochemistry, we present studies of X-ray induced damage of barium nitrate and strontium nitrate. Polycrystalline samples of barium and strontium nitrate were irradiated with high flux monochromatic synchrotron X-rays at selected energies near the K-edge of the respective cations. The damage processes were studied with powder X-ray diffraction, and irradiation products, NO2 and O2, were characterized via Raman spectroscopy. Our results demonstrate that irradiating barium and strontium nitrate with photons of energy greater than the K-edge of the cation promotes a higher rate of decomposition compared to that observed when irradiating with photons of energy below the K-edge. Additionally, differences in X-ray induced damage between the two compounds are examined and discussed, and evidence of the diffusion of irradiation products is presented.

Morphology Modification of Barium Hexaferrite to Nanorod Particle Using Chitosan and Starch as Template

Barium hexaferrite is known as a permanent magnet that has hexagonal or granules morphologies. Magnetic field of barium hexaferrite can be increased by changing its morphology. A rod-shaped barium hexaferrite is expected to result in higher magnetic field compared to granules even though the volumes of both are the same. This study aims to synthesize a rod-shaped barium hexaferrite and to evaluate its magnetic properties. Barium hexaferrite was synthesized using sol-gel method by mixing barium nitrate and iron (III) nitrate nonahydrate with molar ratio of 1:12. Chitosan 1% was added as dispersant and starch 0.5% (w/v) was used as template with variation in volume (5%, 10% and 15% (v/v)). The solution was dried at 100°C for 48 hours and resulting xerogel was then calcined at 1000°C for 2 hours to obtain barium hexaferrite powder. X-Ray D result demonstrated the presence of barium hexaferrite with small fraction of hematite and pure barium hexaferrite. Scanning electron microscopy images showed different concentrations of starch generated different size and morphologies of resulting barium hexaferrite. A rod shaped barium hexaferrite was formed for all samples that prepared using starch template, however hexagonal shape was still found in all samples. The size of resulting barium hexaferrite is decrease by increasing the concentration of starch. Theparticle size of barium hexaferrite measured was 125nm thickness with of 500nmlength for 5% starch, 109 nm thickness and 406 nm length for 10% starch and 62.5 nm thickness and 406 nm length for 15% starch, Barium hexaferrite synthesized without using starch and chitosan produced hexagonal morphology with the thickness of 240-574 nm and length of 574-957 nm. Vibrating Sample Magnetometer showed hysteresis curve as the percentage variation of starch was used, higher amount of starch used tends to increase the values of saturation and remanence. Avery significant increase in coercivity value amounted to 457.1% occurred in the use of 10% starch. It can be concluded that starch can be used as rod-shaped template in sol-gel method to produce barium hexaferrite. By using chitosan and starch in the process of synthesis of barium hexaferrite using sol-gel method can increase the value of the magnetization and the coercivity barium hexaferrite.

Structural and Electrical Properties of Barium Strontium Cobaltite Nanoparticles Synthesized by Wet Chemical Methods

Barium strontium cobaltite (Ba0.5Sr0.5CoO3−δ) nanoparticles were synthesized by using without water and surfactant (WOWS) sol-gel method, co-precipitation method and composite mediated hydrothermal method (CMHM). Co-precipitation synthesis was carried out for 0.4 M precursors solutions of strontium nitrate Sr (NO3)2, cobalt nitrate hexahydrate Co (NO3)2·6H2O and barium nitrate Ba (NO3)2and with the sodium hydroxide NaOH as precipitating agent, sol-gel synthesis was done using ethylene glycol as precipitating agent and the CMHM synthesis was done using sodium hydroxide and Potassium hydroxide (NaOH-KOH) as reactants and precipitating agents at 180 °C for 65 min. Calcination of the synthesized samples was done at 830 °C for 02 hours. Pellets of calcined powder was sintered at 850 °C for 20 minutes. X-ray diffraction (XRD) study was used to find the structural parameters (crystal structure, crystallite size and phase purity). The observed phase transformation of pure barium strontium cobaltite monoclinic to orthorhombic structure was found after heat treatment. Crystallite sizes were calculated by using Scherrer’s formula. Temperature dependent (100 to 600 °C) dc conductivities of the sintered pellets were measured and found to be increased with the successive increase in measuring temperature. Temperature dependent (100 to 600 °C) impedances of all samples synthesized through wet chemical methods at fixed frequency of (10kHz) was also measured and compared. The structural and AC/DC electrical properties were correlated to different synthesis methods. The synthesized samples can be thought as an electrode material for intermediate temperature range solid oxide fuel cells (IT-SOFCs).

Antibacterial and Antibiofilm Activity of Barium Titanate Nanoparticles

In this research work, barium titanate nanoparticles (BaTiO3 NPs) were prepared by a co-precipitation method using barium nitrate and titanium dioxide precursors. The structural and morphological studies of the NPs were carried out by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The XRD pattern confirmed the formation of the BaTiO3 NPs having an average size less than 100 nm. BaTiO3 NPs were also evaluated for their efficacy against the human pathogenic bacteria. Significant antimicrobial and antibiofilm activities of BaTiO3 NPs were observed against P. aeruginosa and S. aureus clinical isolates. Results presented in this work confirm that BaTiO3 NPs can control the growth of biofilm formation activities of pathogenic bacteria at very low concentration and hence suggests their use as alternative antimicrobial agents. This is the first report on chemical method synthesized BaTiO3 NPs for its biofilm inhibition activity.

Synthesis and characterization of BaFe2O4 nano-ferrites for gas sensor applications

BaFe2O4 spinel-type ferrite is synthesized by a simple auto-combustion method. The ferrites are based on spinel structure. The ideal spinel structure consists of the cubic close packing of oxygen anions with the tetrahedral (A site) and octahedral (B site) holes available for metal cation occupancy. Spinel ferrites have combined the both interesting magnetic properties and high electrical resistivity. The barium nitrate and ferric nitrate are taken as raw material, and combustion process is adopted for synthesis. The resultant ash was collected after combustion, and it is annealed at 700 and 900 °C. The synthesized products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectrum and vibrating sample magnetometer. BaFe2O4 nanoparticles exhibit good magnetic property and also possess gas sensing ability. This material is more suitable for high-temperature gas sensor to support for clean environment.

Characterization of Phase Evolution, Microstructure and Electrical Properties of Sol-Gel Auto-Combustion Derived BCZT Ceramics.

This work aims to study the effect of sintering temperature on properties of barium calcium zirconate titanate (BCZT) ceramics. The BCZT is a Pb-free material that shows excellent piezoelectric properties. In this study, BCZT ceramics were prepared from BCZT powders synthesized from barium nitrate, calcium nitrate, zirconium (IV) oxynitrate hydrate, titanium (IV) butoxide and citric acid precursors by the sol-gel auto-combustion method. The BCZT powder was calcined at the temperature ranging from 700 to 1000 °C. Green bodies were sintered at various temperatures (1200-1450 °C). The X-ray diffraction patterns showed only non-crystalline phase of as-burnt powder. For the calcined powders, XRD patterns showed that the amount of crystalline, perovskite phase increased with increasing calcination temperature. The crystalline particles have a spherical shape and the size in the range of 25-35 nm. For the BCZT ceramics sintered at 1200-1300 °C, the density tended to increase with increasing sintering temperature. Very high bulk densities of 5.62-5.63 g/cm3 (which were higher than those of the ceramics synthesized by the wet-chemical method) were achieved at the sintering temperature of 1400-1450 °C. Ceramics produced at these temperatures possessed fully-developed microstructures, very good dielectric properties as well as high response of polarization and strain to applied electric field.