scholarly journals Synthesis and Study of Microcrystalline Parameters with Electrical Conductivity of Al Doped Lithium Ferrites

2017 ◽  
Vol 14 (2) ◽  
pp. 185-189
Author(s):  
Suresh. S Darokar
Keyword(s):  
Mass Density ◽  
Hexagonal Phase ◽  
Average Particle Size ◽  
Solid State Reaction Method ◽  
Average Particle ◽  
Ferrous Ions ◽  
Xrd Pattern ◽  
Lithium Ferrites ◽  
General Chemical ◽  
Ray Density

Magnetoplumite type of lithium ferrites substituted by aluminium ions having general chemical formula Li0.5Fe0.5+xAl12-X O19 (where x = 1 to 6) were prepared by standard solid state reaction method The compounds are in single hexagonal phase without traces of uncertainly ambiguous reflection. From XRD pattern lattice parameters has recorded with increasing doped aluminium element in the range from a = 5.807 Å to 5.906 Å and c = 22.507 Å to 22.585 Å pertaining the space group P63/mmc (No.194). The mass density of the ferrites were found linearly varies and depends upon the mass and volume of sample. The X-Ray density has depends upon the lattice constant and molecular weight of the compounds. The average particle size was also estimated. Electrical properties such as dc conductivity, activation energy were studied. Also, the type of carriers responsible in each was determined from thermoelectric studies. The higher resistivity of the compounds Li0.5Fe0.5+xAl12-X O19 suggests less presence of mixed valency cations on equivalent lattice. While Fe show low value due to the ferrous ions present on the octahedral sites along with ferric ions.

Influence of Excess Bi2O3 and Na2Co3 on Crystal Structure and Microstructure of Bismuth Sodium Titanate Ceramics

2011 ◽  
Vol 474-476 ◽  
pp. 1711-1714 ◽  
Author(s):  
Panadda Sittiketkron ◽  
Arrak Klinbumrung ◽  
Theerachai Bongkarn
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Perovskite Phase ◽  
Average Particle Size ◽  
Sodium Titanate ◽  
Solid State Reaction Method ◽  
Lattice Parameter ◽  
Rhombohedral Structure ◽  
Average Particle ◽  
Average Grain Size

This study investigated the influence of excess Bi2O3 and Na2CO3 on the crystal structure, microstructure and dielectric properties of (Bi0.5Na0.5)TiO3 (BNT) ceramics. The BNT ceramics were synthesized using the solid-state reaction method with various excess Bi2O3 and Na2CO3 levels (0, 1, 2, 3 and 4 mol%). The X-ray characterization revealed that all samples had a rhombohedral structure. A pure perovskite phase was obtained in all samples. The lattice parameter a tended to increase with increased excess Bi2O3 and Na2CO3 content in the calcined powders and sintered ceramics. The average particle size increased while, the average grain size tended to decreased with increased of excess Bi2O3 and Na2CO3 content. The depolarization temperature (Td) and the Curie temperature (Tc) were slightly decreased with the increase of excess Bi2O3 and Na2CO3 content. The dielectric properties were related to the density.

scholarly journals Growth of significantly low dimensional zinc orthotitanate (Zn2TiO4) nanoparticles by solid state reaction method

2018 ◽  
Vol 50 (1) ◽  
pp. 133-138 ◽  
Author(s):  
Lizina Khatua ◽  
Rudrashish Panda ◽  
Avanendra Singh ◽  
Arpan Nayak ◽  
Pravakar Satapathy ◽  
...  
Keyword(s):  
Particle Size ◽  
Solid State ◽  
Surface Area ◽  
Solid State Reaction ◽  
Average Particle Size ◽  
Cost Effective ◽  
Solid State Reaction Method ◽  
Average Particle ◽  
Reaction Method ◽  
Low Dimensional

In this work, the ZnO-TiO2 mixed phase nanoparticles were prepared by solid state reaction method by using ZnO and TiO2 powder as precursors. The X-ray diffraction pattern shows a dominant phase of Zinc Orthotitanate (Zn2TiO4). The average particle size (58?18 nm) calculated by the analysing FESEM data closely matches with the particle size calculated by Scherrer?s equation. The calculated average particle size is significantly smaller than the previously published results of nanoparticles, prepared by same method. In the Brunauer-Emmett-Teller (BET) study the specific surface area of the nanoparticles was found as 8.78 m2/g which is similar to the surface area reported in this material prepared by mechanochemical method. The method which we report is simpler and cost effective unlike the previous reported.

scholarly journals Study Microstructure of Fe3O4 Modification Using PEG 4000 form Iron Sand at Wari Ino Beach As A Biosensor Application

2021 ◽  
Vol 8 (3) ◽  
pp. 168-171
Author(s):  
Kurnia Kurnia ◽  
Meidy Kaseside ◽  
Steven Iwamony
Keyword(s):  
Average Particle Size ◽  
Precipitation Method ◽  
High Dispersion ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Peg 4000 ◽  
Biosensor Application ◽  
Scherrer Formula ◽  
Co Precipitation

Fe3O4 encapsulated PEG form iron sand at wari ino beach has been successfully synthesized by co-precipitation method. The average particle size  of the nanoparticle 11,3 nm was determined by scherrer formula. Fe3O4 modification PEG 4000 was successfully encapsulated the samples  by the presence C-O-C and CH bonding that were characterized using Fourier Transform Infra Red (FTIR), X-Ray Diffraction (XRD) pattern  shows that all samples  are formed by single  phase cubic spinel magnetite  , and Scanning Electron Microscopy (SEM) shows the  high dispersion capability while encapsulated process using  PEG. The results of the characterization show that the Fe3O4 successfully encapsulated by PEG 4000.

Co-Doped ZnO Nano-Agglomerates as a Potential Scaffold for Non-Enzymatic Hydrogen Peroxide Sensing

2021 ◽  
Vol 13 (9) ◽  
pp. 1732-1738
Author(s):  
Ahmad Umar ◽  
Ramesh Kumar ◽  
Rajesh Kumar ◽  
Ahmed A. Ibrahim ◽  
Mohsen A. M. Alhamami ◽  
...  
Keyword(s):  
Hexagonal Phase ◽  
Average Particle Size ◽  
Solution Process ◽  
Average Particle ◽  
Spherical Nanoparticles ◽  
Cyclic Voltammetric ◽  
Wurtzite Hexagonal Phase ◽  
Dynamic Concentration ◽  
Doped Zno ◽  
Co Doped

Co-doped ZnO nano-agglomerates were synthesized by a facile solution process. Several characterization techniques revealed the successful doping of the ZnO by Co ions. FESEM results showed the agglomeration of the Co-doped ZnO nanoparticles to form large-sized nano-agglomerates. The diameters of the spherical nanoparticles and the agglomerates were not found to be uniform. The diameters of the nano-agglomerates ranged from ~25 nm–120 nm. XRD spectrum confirmed the Wurtzite hexagonal phase of ZnO in Co-doped ZnO nanoagglomerates. The average particle size for Co-doped ZnO nano-agglomerates was 20.68 nm. The sensing parameters were examined by using Co-doped ZnO nano-agglomerates modified gold electrode through cyclic voltammetric and amperometric analysis. The sensitivity of 70.73 μAmM−1cm−2 and very low-detection limit of 0.2 μM was observed for H2O2. The corresponding linear dynamic concentration range was 0.2–1633 μM. The excellent sensing activities of the Co-doped ZnO nano-agglomerates for H2O2 were attributed to the improved intrinsic electric properties and increased inner defects density, particularly near the interface region.

Blue Fluorescence in Doped LaF3 Nanocrystals Synthesized by Microwave Technique

2012 ◽  
Vol 584 ◽  
pp. 219-223
Author(s):  
S.G. Gaurkhede ◽  
M.M. Khandpekar ◽  
S.P. Pati ◽  
A.T. Singh
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Hexagonal Phase ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Blue Fluorescence ◽  
Tem Analysis ◽  
Selected Area Electron Diffraction ◽  
20 Nm

Hexagonal-phase LaF3: Ce3+, Pr3+, and Sm3+ doped (LCPS) nano-crystals have been synthesized by keeping same molarities of rare earth elements using aqueous route. The samples have been synthesized in conventional microwave on low power range in about an hour’s time. The phase formation has been verified by powder X-ray diffraction (XRD).Hexagonal geometry of the LCPS nano-crystals has been observed with an average particle size of 20 nm by TEM analysis. The JCPDS Card No. (32-0483) and selected area electron diffraction (SAED) pattern has been used for identification of crystal structure. The UV- VIS spectra indicated band gap of 5.00eV. The FTIR spectrums have been used for assignment of fundamental vibrations. Blue fluorescence observed with exciting wavelengths of 254 nm respectively. The presence of rare-earth elements in LCPS nano-crystals have been verified by the EDAX spectra.

scholarly journals Single-Step Synthesis of Manganese Ferrite Nanoparticles with Enhanced Magnetization via Chemical Co-precipitation Route

2019 ◽  
Vol 11 (2) ◽  
pp. 225-234
Author(s):  
S. Pande ◽  
M. M. Islam ◽  
S. C. Mohanta ◽  
Nasir Uddin
Keyword(s):  
Magnetic Properties ◽  
Average Particle Size ◽  
Average Crystallite Size ◽  
Ferrite Nanoparticles ◽  
Single Step ◽  
Average Particle ◽  
Manganese Ferrite ◽  
Xrd Pattern ◽  
One Step ◽  
Co Precipitation

Single-domain manganese ferrite nanoparticles were synthesized through one-step chemical co-precipitation technique using diethanolamine which acted simultaneously as precipitating and capping agent. The synthesized nanoparticles were characterized by XRD, FTIR, TGA, EDX, FESEM and VSM. XRD pattern showed the presence of peaks corresponding to the single-phase inverse spinel structure with an average crystallite size of 59.6 nm. The average particle size determined by FESEM was 46.8 nm. In addition, the magnetic properties of the nanoparticles analyzed by VSM exhibited nearly superparamagnetic property with a high saturation magnetization of 77.31 emu/g with little coercivity (10.53 emu/g) and remanence (9.32 emu/g) at 300 K temperature. TGA and FTIR results confirmed the binding of diethanolamine onto the surface of manganese ferrite nanoparticles. The synthesized nanoparticles exhibited single crystalline phase with improved magnetic properties.  

Influences of Firing Temperatures on Phase and Morphology Evolution of (Ba0.25Sr0.75)(Zr0.75Ti0.25)O3 Ceramics Synthesized via Solid-State Reaction Method

2009 ◽  
Vol 421-422 ◽  
pp. 247-250 ◽  
Author(s):  
Atthakorn Thongtha ◽  
Kritsana Angsukased ◽  
Theerachai Bongkarn
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Perovskite Phase ◽  
Average Particle Size ◽  
Solid State Reaction Method ◽  
Lattice Parameter ◽  
Average Particle ◽  
Strontium Zirconate ◽  
Reaction Method ◽  
Average Grain Size

The effect of calcination (1000-1400 oC) and sintering temperatures (1400-1600 oC) on the phase formation and microstructure of barium strontium zirconate titanate [(Ba0.25Sr0.75)(Zr0.75Ti0.25)O3; BSZT] ceramics were investigated. BSZT powders were prepared by the solid-state reaction method. Higher calcination temperatures increased the percentage of the perovskite phase, but decreased the lattice parameter a of BSZT powders. The pure perovskite phase of BSZT powders was detected above the calcination temperature of 1350 oC. The microstructure of BSZT powders exhibited an almost-spherical morphology and had a porous agglomerated form. The average particle size and the average grain size of the ceramics were increased with the increase of calcination and sintering temperatures. The highest density of the samples was 5.42 g/cm3 which was obtained from ceramic sintered at 1550 oC for 2 h.

The concentration quenching of photoluminescence in Eu3+-doped La2O3

2013 ◽  
Vol 37 (1) ◽  
pp. 47-54 ◽  
Author(s):  
V. Đorđević ◽  
Ž. Antić ◽  
M. G. Nikolić ◽  
M. D. Dramićanin
Keyword(s):  
Room Temperature ◽  
Hexagonal Phase ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Lifetime ◽  
Transmission Electron ◽  
Lifetime Value ◽  
Kinetics Of

Abstract This work explores the influence of dopant concentration on photoluminescent emission and kinetics of Eu3+-doped (0.2−10 at.%) nanocrystalline lanthanumoxide powders. The X-ray diffraction analysis confirmed that all samples crystallize in La2O3 hexagonal phase with space group P3¯ m1. Transmission electron microscopy showed particles with non-uniform shape and diverse size distribution with an average particle size of (95 ± 5) nm. The room temperature photoluminescence spectra of all samples contain characteristic Eu3+ luminescence lines with the most pronounced red 5D0 →7F2 emission at about 626 nm. The maximum intensity of red emission is observed for the sample containing 5at.% of Eu3+ ions. The emission kinetics was recorded in the temperature range from 10K to 300 K. The maximum lifetime value of 0.98 ms obtained for the sample with 0.5at.% Eu3+ at room temperature increases up to 1.3ms at 10 K.

Synthesis and Characterization of High Density and Low Temperature Sintered Proton Conductor BaCe0.5Zr0.35In0.1Zn0.05O3-δ

2015 ◽  
Vol 1098 ◽  
pp. 104-109 ◽  
Author(s):  
Abul Kalam Azad ◽  
D.D.Y. Setsoafia ◽  
L.C. Ming ◽  
Iskandar Petra
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Proton Conductor ◽  
Solid State Reaction Method ◽  
Proton Conductors ◽  
Orthorhombic Symmetry ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Proton Uptake

Rare-earth-doped BaCeO3and BaZrO3electrolytes with perovskite structure have been studied extensively in developing proton conducting intermediate temperature SOFC. Acceptor doped alkaline earth cerates and zirconates have been thoroughly studied because of the great interest in their possible applications as solid proton conductors. The perovskite type proton conductor BaCe0.5Zr0.35In0.1Zn0.05O3-δwas prepared in the traditional solid state reaction method. The density of the sample obtained about 96% of the theoretical density after sintering at 1350 °C and X-ray diffraction study confirms the pure phase. Rietveld refinement of the neutron and X-ray powder diffraction data shows that this material crystallizes in the orthorhombic symmetry in the space group Pm3m. Particle size measurement shows that the average particle size is about 2.4 μm. The average thermal expansion at 894 °C was 9.49 x 10-6/°C. Thermogravimetric analysis (TGA) traces obtained for the sample on heating in wet air shows that the maximum proton uptake occurs from 595 °C.

SYNTHESIS AND CHARACTERIZATION OF n-BUTYL 4-(3,4-DIMETHOXYPHENYL)-6-METHYL-2-THIOXO-1,2,3,4 TETRAHYDROPYRIMIDINE-5-CARBOXYLATE NANOCRYSTALLINE PARTICLES BY WATER/OIL MICROEMULSION METHOD

2011 ◽  
Vol 10 (06) ◽  
pp. 1237-1244 ◽  
Author(s):  
POORVESH M. VYAS ◽  
MIHIR J. JOSHI ◽  
AKSHAY M. PANSURIYA ◽  
YOGESH T. NALIAPARA
Keyword(s):  
Average Particle Size ◽  
Butyl Alcohol ◽  
Average Particle ◽  
Dielectric Study ◽  
Xrd Pattern ◽  
Transmission Electron ◽  
Nanocrystalline Particles ◽  
Ft Ir ◽  
Biginelli Condensation

Various pyrimidine derivatives are well known for their different pharmaceutical applications. The n-butyl 4-(3, 4-dimethoxyphenyl)-6-methyl-2-thioxo-1,2,3,4 tetrahydropyrimidine-5-carboxylate (n-butyl THPM) was synthesized by using n-butylacetoacetate. The n-butyl acetoacetate was obtained by transesterification of ethyl acetoacetate with n-butyl alcohol using Biginelli condensation. The synthesized powder was used to obtain the nanoparticles of n-butyl THPM by using water/oil microemulsion technique. The average particle size was calculated from the powder XRD pattern by applying Scherrer's formula. The nanoparticles of n-butyl THPM were observed by Transmission Electron Microscope (TEM). The diameter of the nanoparticles varied from 15 nm to 65 nm. The nanoparticles were also characterized by FT–IR spectroscopy, TG–DTA–DSC and mass spectroscopy. The n-butyl THPM nanoparticles were stable up to 280°C. Thermodynamic and kinetic parameters of decomposition were obtained by applying Coats and Redfern relation to the thermogram. The dielectric study was carried out in the frequency range of 50 Hz to 5 MHz. The dielectric constant, dielectric loss and ac conductivity decreased as the frequency of applied field increased.

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