scholarly journals First Nanoparticles of a Conductor Based on the Organic Donor Molecule BETS: κ-(BETS)2FeCl4

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4444
Author(s):  
Kane Jacob ◽  
Christophe Faulmann ◽  
Dominique de Caro ◽  
Lydie Valade
Keyword(s):  
Energy Gap ◽  
Molar Ratio ◽  
Saturation Current ◽  
X Ray Diffraction ◽  
Donor Molecule ◽  
X Ray ◽  
Nano Crystalline ◽  
Current Voltage ◽  
Diffraction Patterns ◽  
Shockley Diode Model

Nanoparticles of the molecular superconductor (BETS)2FeCl4 were obtained by the electrochemical oxidation of BETS in the presence of [(C2H5)4N]FeCl4 and an amphiphilic imine (OATM), acting as a growth controlling agent. When the reaction was carried out with a molar ratio OATM/BETS of 10, roughly spherical nanoparticles exhibiting sizes in the 10–40 nm range were observed. X-ray diffraction patterns evidenced the growth of (BETS)2FeCl4 nanoparticles with the κ-type structure. The current-voltage characteristic recorded on an individual nanoparticle aggregate was fitted with a Shockley diode model. A saturation current of 1216 pA and a threshold voltage of 0.62 V were extracted from this model. This latter value was consistent with roughly half of the energy gap of the semiconducting nano-crystalline aggregate.

Synthesis, Structural, Morphological and I-V Characteristics of Polyaniline-MgCl Composite

2022 ◽  
Vol 1048 ◽  
pp. 141-146
Author(s):  
Madihally Nagaraja ◽  
Geetha Thippeswamy ◽  
Sushma Prashanth ◽  
Jayadev Pattar ◽  
Mahesh Hampapatna Mahesh
Keyword(s):  
Structural Analysis ◽  
Oxidative Polymerization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sem Micrographs ◽  
Morphological Studies ◽  
Current Voltage ◽  
Amorphous Nature ◽  
Diffraction Patterns ◽  
Polymerization Method

Composite of polyaniline-MgCl has been synthesized using oxidative polymerization method. Synthesized samples were characterized for structural analysis using FTIR and XRD. Morphological studies were carried by SEM micrographs. Current-Voltage (I-V) properties are obtained through Kiethly source meter. FTIR spectrum of polyaniline-MgCl composite indicates all the characteristic peaks of polyaniline. X-ray diffraction patterns represented the amorphous nature of polyaniline-MgCl composite. SEM micrographs confirmed the presence of MgCl particles in polyaniline matrix. I-V characteristics have shown the ohmic type behavior of polyaniline and polyaniline-MgCl composite.

Characterization of Nano-Biphasic Calcium Phosphates Synthesized under Microwave Curing

2008 ◽  
Vol 3 ◽  
pp. 67-87 ◽  
Author(s):  
Wafa I. Abdel-Fattah ◽  
Fikry M. Reicha ◽  
Tarek A. Elkhooly
Keyword(s):  
Ph Value ◽  
Calcium Phosphates ◽  
Chemical Precipitation ◽  
Calcium Deficiency ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Curing ◽  
Tcp Phase ◽  
Diffraction Patterns

Two biphasic BCP ceramic samples were synthesized by chemical precipitation and microwave curing of calcium deficient hydroxyapatite CDHA under the same pH value and temperature but varied in their initial Ca/P molar ratio. Precipitates were characterization after thermogravimetric analysis, fourier transform infrared spectroscopy, X-ray diffraction, atomic absorption spectroscopy and TEM. Hydroxyapatite (HA) contents were measured for the two biphasic calcium phosphate (BCP) ceramics by sintering the calcium-deficient apatites (CDHA). The results reveal two condensation mechanisms of HPO42- affecting the Ca/P molar ratio after calcination. The X-ray diffraction patterns of BCP powders show the in situ formation of -TCP in the BCP powder. The amount of -TCP phase increases as the initial Ca/P molar ratio decreases due to more calcium deficiency in CDHA structure. The influence of HPO42- incorporation on increasing -TCP phase content after calcination is evaluated. TEM micrographs proved the effect of microwave curing during the preparation process on reducing of particle size to nanoscale range and the destruction of CDHA to finer HA and -TCP particles upon calcination.

scholarly journals Band Gap Tailoring, Size Modulation and Photoluminescence Properties of Mn/Cu doped ZnS Nanostructures

2021 ◽  
Author(s):  
P.J. Binu ◽  
S. Muthukumaran
Keyword(s):  
Energy Gap ◽  
Effective Control ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Light Emitting ◽  
X Ray ◽  
Cubic Structure ◽  
Diffraction Patterns ◽  
Co Precipitation ◽  
Band Gap Tailoring

Abstract ZnS, Mn added ZnS (Zn0.97Mn0.03S) and Mn, Cu dual doped ZnS (Zn0.95Mn0.03Cu0.02S) QDs have been prepared using co-precipitation technique. The influence of Mn and Cu addition on the morphology, structure and photoluminescence properties of Mn/Cu incorporated ZnS have been examined. Cubic structure of the synthesized samples was confirmed by X-ray diffraction patterns. The incorporation of Cu in Zn-Mn-S lattice not only decreased the particle/grain size and also generates more defect based luminescent activation centres. The reduced energy gap by Mn addition was explained by sp-d exchange interaction and the elevated energy gap in Cu, Mn dual doped ZnS was expalined by Burstein–Moss effect. The tuning phenomenon of size as well as the energy gap in ZnS by Mn/Cu addition promote these materials for nano-electronic applications. FTIR spectra confirmed the presence of Mn/Cr-Zn-S bondings. The substitution of Mn /Cu provides an effective control over tuning of different emission colours which signifies their applications like light emitting diodes.

Microstructural evolution of mullites produced from single-phase gels

2007 ◽  
Vol 40 (2) ◽  
pp. 260-276 ◽  
Author(s):  
Marek Andrzej Kojdecki ◽  
Esther Ruiz de Sola ◽  
Francisco Javier Serrano ◽  
Estefanía Delgado-Pinar ◽  
María Mercedes Reventós ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Unit Cell ◽  
Molar Ratio ◽  
Model Parameters ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Transmission Electron ◽  
Diffraction Patterns

The crystalline microstructure of mullites obtained by heating monophasic gels has been investigated. Gels with alumina to silica molar ratio of 3:2 (as in secondary mullite) and 2:1 (as in primary mullite) were prepared by gelling mixtures of aluminium nitrate and tetraethylorthosilicate. Phase transformations were induced by heating the gel precursors, with different final treatment temperatures between 1173 and 1873 K. The mullites formed as a result of thermal treatment were studied by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The crystalline structure (unit-cell parameters) and microstructure were determined from X-ray diffraction patterns. The formation of mullites of homogeneous chemical composition and with unit-cell parameters depending almost linearly on the treatment temperature was found. Their compositions, expressed as alumina to silica molar ratio, were determined from the unit-cell parameters and were in the range of those characterizing primary and secondary mullites. Mullites processed at lower temperatures were accompanied by small amounts of vitreous phase. The crystalline microstructure of the obtained mullites was interpreted by means of a mathematical model of polycrystalline material, involving prevalent crystallite shape, volume-weighted crystallite size distribution and second-order crystalline lattice strain distribution as model parameters. The model parameters were determined for each sample by modelling its X-ray diffraction pattern and fitting it to a measured pattern. Bimodality of the size distribution was observed and explained as a consequence of two crystallite nucleation and growth processes, which started from small alumina-rich and alumina-poor domains, spontaneously formed in a precursor gel at early stages of heating. Images produced by scanning and transmission electron microscopy agreed well with the characteristics obtained from the analysis of the X-ray diffraction patterns.

Effects of In-Situ DC-Bias on the Composition, Microstructures and Dielectric Properties of RF Magnetron Reactive Sputtered (Ba,Sr)TiO3 Films

1999 ◽  
Vol 596 ◽  
Author(s):  
Wen-Hao Chan ◽  
Hui-Ling Shen ◽  
Lih-Hsin Chou ◽  
Jinn-Lung Wang ◽  
Jyi-Ching Tsai
Keyword(s):  
Dielectric Constant ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
Alloy Target ◽  
Bst Films ◽  
Dc Bias ◽  
Diffraction Patterns

AbstractThin films of (Ba,Sr)TiO3 (BST) have been prepared by rf magnetron reactive sputtering using single alloy target, and in-situ negative DC-bias. Post annealing was applied to the asdeposited films at 620°C for 2 hours in 1 atm oxygen atmosphere. Thin film microstructures and grain sizes were studied and calculated by means of X-ray diffraction, while the film composition was analyzed by Electron Probe X-ray Microanalyzer (EPMA). The dielectric constant of the films was also studied. As the applied DC-bias increased, the dielectric constant increased from 176 to 912, the x-ray diffraction patterns became more intense and narrower, and the (Ba+Sr)/Ti molar ratio increased from 0.70 to 0.83. In-situ DC-bias was observed to be a feasible fabrication process to increase the grain size and relative permittivity of sputtered BST films.

Synthesis and Characterization of CoMn2O4 Nanopowders by a Reverse Micelle Processing

2016 ◽  
Vol 868 ◽  
pp. 105-110
Author(s):  
Dong Sik Bae
Keyword(s):  
Reverse Micelle ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrd Diffraction ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
Average Size

CoMn2O4 nanoparticles were synthesized by reverse micelle processing from the mixed precursor (consisting of Co (NO3)2 ·6H2O and MnCl2·4H2O). The CoMn2O4 was prepared by mixing the aqueous solution at a molar ratio of Co : Mn = 1 : 2. The synthesized powders were calcined at 600°C for 2h. The average size and distribution of synthesized powders were in the range of 10-20nm and narrow, respectively. The average size of the synthesized powders increased with increasing water to surfactant molar ratio. The XRD diffraction patterns show that the phase of CoMn2O4 was spinel (JCPDS no.77-0471). The synthesized and calcined powders were characterized by thermogravimetry-differential scanning calorimeter (TG-DSC), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The magnetic property of the powder was measured by Vibrating Sample Magneto-meter (VSM) at 298K. The effect of synthesis parameter, such as the molar ratio of water to surfactant, is discussed.

scholarly journals Effect of Molar Ratio on Structural and Size of ZnO/C Nanocomposite Synthesized Using a Colloidal Method at Low Temperature

2019 ◽  
Vol 19 (2) ◽  
pp. 422
Author(s):  
Siham Lhimr ◽  
Saidati Bouhlassa ◽  
Saidati Bouhlassa ◽  
Saidati Bouhlassa ◽  
Bouchaib Ammary ◽  
...  
Keyword(s):  
Room Temperature ◽  
Optical Band Gap ◽  
Hexagonal Wurtzite Structure ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Colloidal Method ◽  
Uv Visible ◽  
Diffraction Patterns

In this paper we study the effects of different molar ratio R of Zn2+ to OH– (R= nOH–/nZn(II) of the precursor was investigated by varying the amount of NaOH. Samples have been synthesized by the colloidal method at room temperature using (ZnCl2), citric acid (C6H8O9·H2O) and sodium hydroxide (NaOH). The formation of ZnO/C composite was characterized by The X-ray diffraction patterns indicated a high crystallinity and nanocrystalline size of ZnO with hexagonal wurtzite structure. The morphologies of the particles have been studied with a scanning electronic microscopy (SEM). The existence of carbon into the composite was detected by FTIR and EDS. The optical band gap of various ZnO/C composite was calculated from UV-Visible absorption measurement varied in the range 3.301 to 3.282 eV according to R values.

Study on the Reaction Mechanism of Al-ZrO2-B4C System

2011 ◽  
Vol 675-677 ◽  
pp. 839-842 ◽  
Author(s):  
He Guo Zhu ◽  
Da Chu ◽  
Huan Wang ◽  
Jing Min ◽  
Ying Lu Ai
Keyword(s):  
Reaction Mechanism ◽  
Volume Fraction ◽  
Exothermic Peak ◽  
Molar Ratio ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Zro2 System

The composite (a-Al2O3+ZrC+ZrB2)/Al has been fabricated by using exothermic dispersion synthesis. When the reinforcement volume fraction is 100%, there are two exothermic peaks occurred in DSC curve of the Al-ZrO2 system. But when the reinforcement volume fraction is 30%, there is only one exothermic peak occurred in the DSC curve and the height of it decreases. When the molar ratio of B4C/ZrO2 is 0, the reaction products are consisted of a-Al2O3 grains and Al3Zr blocks. With an increase in the molar ratio of B4C/ZrO2, the amount of the Al3Zr decreases and the phases of ZrB2 and ZrC are formed. When the molar ratio of B4C/ZrO2 increases to 1/3, the Al3Zr almost disappear and the reinforcements of the composites are composed of a-Al2O3, ZrC and ZrB2. The corresponding XRD (X-ray diffraction) patterns also testify this.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Sign in / Sign up

Export Citation Format

Share Document