Electrochemical Performance of Nanocrystalline Zinc Ferrite Films Synthesized Using Electrodeposition

Nanocrystalline spinel zinc ferrite ZnFe2O4 thin film has been studied and synthesized via the electrodeposition-anodization process. Electrodeposited ZnFe2 alloys were obtained from aqueous sulphate bath. The resulted alloys were electrochemically oxidized in strong alkaline solution (1 M KOH) at room temperature to the analogous hydroxides. The electroanodized ZnFe2 alloy film was annealed in air at 400 °C for 2 h to get the required zinc ferrite. The electrochemical factors controlling of the electrodeposition of ZnFe2 alloys such as the bath temperature, agitation, the current density were studied and optimized. The crystal structure, crystal size and microstructure of the produced ferrites were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The deposited film was mainly composed of ZnFe2O4 based on XRD studies. The produced film had a spinel structure and the crystallite size was 4.9 nm. SEM micrograph of the resulted zinc ferrite particles shows compact crystallites shapes and agglomerated chains with smallest semicircular particles like morphology.

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PHOTOLUMINESCENCE OF NON-CRYSTALLINE ALUMINA NANOWIRES SYNTHESIZED BY DIRECT ANODIZATION OF ALUMINUM

Modern Physics Letters B ◽

10.1142/s0217984909019995 ◽

2009 ◽

Vol 23 (14) ◽

pp. 1819-1825

Author(s):

JAYA SARKAR ◽

GOBINDA GOPAL KHAN ◽

A. BASUMALLICK

Keyword(s):

Light Emission ◽

Pure Aluminum ◽

Bath Temperature ◽

Constant Current ◽

X Ray Diffraction ◽

Constant Current Density ◽

X Ray ◽

Anodization Process ◽

Potential Applications ◽

Crystalline Alumina

Alumina nanowires have been synthesized by a simple electrochemical route, by tailoring the anodization process of aluminum. Two-stage anodization of pure aluminum foils were carried out in 0.3 M oxalic acid electrolyte by maintaining a constant current density of 250 A/m2 and suitably controlling the other anodization parameters: anodization voltage, bath temperature and anodization time. The fabricated alumina nanowires were investigated by field-emission scanning electron microscope (FE-SEM) and energy dispersive X-ray spectroscopy (EDS). Moreover, the X-ray diffraction (XRD) study on the prepared nanowires shows that they are non-crystalline in nature. The photoluminescence (PL) spectra of alumina nanowires exhibit two stable emission bands at 438 and 581 nm. The blue luminescence behavior of the alumina nanowires are attributed to the oxygen-deficient defect centers. PL study of alumina nanowires shows that they have potential applications in light emission devices.

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Characterization and Magnetic Properties of Zinc Ferrite Synthesized by Combustion Route

Journal of Nanoscience and Technology ◽

10.30799/jnst.170.18040519 ◽

2018 ◽

Vol 4 (5) ◽

pp. 536-538

Author(s):

Anil S. Jadhav ◽

B. Raghunanda ◽

Ashok D. Shetkar ◽

Ajai Kumar S. Molakeri

Keyword(s):

Magnetic Properties ◽

Zinc Ferrite ◽

Room Temperature ◽

Combustion Method ◽

Nanocrystalline Powder ◽

Vibrating Sample Magnetometer ◽

X Ray Diffraction ◽

Field Range ◽

X Ray ◽

Combustion Route

Zinc ferrite (ZnFe2O4) nanocrystalline powder material was prepared by combustion method. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) is used to study on structural properties. The magnetic properties of the sample were measured at room temperature using vibrating sample magnetometer (VSM) in the field range �15000 G. Hysteresis loop obtained room temperature for ZnFe2O4 nanoparticles indicates that the nanoparticles are ferromagnetic in nature.

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InSe Nanothin Film with Ar-Gas Low Vacuum Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.606.15 ◽

2014 ◽

Vol 606 ◽

pp. 15-18

Author(s):

Falah I. Mustafa ◽

Mooroj Ali

Keyword(s):

Thin Films ◽

Diffraction Analysis ◽

Room Temperature ◽

Energy Gap ◽

X Ray Diffraction ◽

Argon Gas ◽

X Ray ◽

Glass Substrates ◽

Deposited Film ◽

Deposited Films

InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~500nm by thermal evaporation technique. The X-Ray diffraction analysis showed that both the as-deposited films In2Se3and InSe (x= 0.4 and 0.5) are amorphous in nature while the as-deposited film In3Se2is polycrystalline and the values of energy gap are Eg=1.44eV for In2Se3, Eg=1.16eV for InSe and Eg=0.78eV for In3Se2. The same technique used with insert Argon gas at pressure 0.1 mbar where InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~100nm. The X-Ray diffraction analysis showed that the as-deposited films In2Se3are amorphous in nature while the as-deposited film InSe and In3Se2are Nanocrystalline with grain size 33nm and 55nm respectively and the values of energy gap are Eg=1.55eV for InSe and Eg=1.28eV for In3Se2. The energy gap of InSe thin films increase with Argon gas assist and phases changes from amorphous and polycrystalline to nanostructure material by thermal vacuum deposition technique.

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Mechanical Amorphization and Recrystallization of Mn-Co(Fe)-Ge(Si) Compositions

Metals ◽

10.3390/met9050534 ◽

2019 ◽

Vol 9 (5) ◽

pp. 534 ◽

Cited By ~ 1

Author(s):

Antonio Vidal-Crespo ◽

Jhon J. Ipus ◽

Javier S. Blázquez ◽

Alejandro Conde

Keyword(s):

Room Temperature ◽

Crystal Size ◽

Milling Time ◽

Phase Evolution ◽

Intermetallic Phases ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Bcc Phase ◽

Thermal Stability Of

Mechanical alloying using a planetary ball mill allowed us to obtain two homogeneous systems formed by units with nanometer size and MnCo0.8Fe0.2Ge1−xSix stoichiometry (x = 0 and 0.5). The phase evolution of the systems with the milling time was analyzed using X-ray diffraction. Thermal stability of the final products was studied using differential scanning calorimetry. Room temperature 57Fe Mössbauer spectroscopy was used to follow the changes in the Fe environments. A paramagnetic Co-based amorphous phase developed in both alloys as milling progressed. However, while the presence of Si stabilized the Mn-type phase, mechanical recrystallization was observed in a Si-free composition leading to the formation of a MnCo(Fe)Ge intermetallic (Pnma space group) with a crystal size of 7 ± 1 nm. Mössbauer results indicate that Fe atoms migrate from the initial bcc phase to the amorphous and intermetallic phases.

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Impedance spectroscopic and dielectric properties of nanosized Y2/3Cu3Ti4O12 ceramic

Journal of Advanced Dielectrics ◽

10.1142/s2010135x14500301 ◽

2014 ◽

Vol 04 (04) ◽

pp. 1450030 ◽

Cited By ~ 14

Author(s):

Sunita Sharma ◽

Shiv Sundar Yadav ◽

M. M. Singh ◽

K. D. Mandal

Keyword(s):

Room Temperature ◽

Saed Pattern ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Bright Field ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Nanocrystalline Particle ◽

Sem Micrograph ◽

Modulus Studies

Yttrium Copper Titanate ( Y 2/3 Cu 3 Ti 4 O 12) nanoceramic is structurally analogous to CaCu 3 Ti 4 O 12 (CCTO). X-ray diffraction (XRD) of Y 2/3 Cu 3 Ti 4 O 12 (YCTO) shows the presence of all normal peaks of CCTO. SEM micrograph exhibits the presence of bimodal grains of size ranging from 1–2 μm. Bright field TEM image clearly displays nanocrystalline particle which is supported by presence of a few clear rings in the corresponding selected area electron diffraction (SAED) pattern. It exhibits a high value of dielectric constant (ε′ = 8434) at room temperature and 100 Hz frequency with characteristic relaxation peaks. Impedance and modulus studies revealed the presence of temperature-dependent Maxwell–Wagner type of relaxation in the ceramic.

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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Electron Microscope study of commensurate-incommensurate phase transition in BaZnGeO4

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173996 ◽

1990 ◽

Vol 48 (4) ◽

pp. 172-173

Author(s):

Naoki Yamamoto ◽

Makoto Kikuchi ◽

Tooru Atake ◽

Akihiro Hamano ◽

Yasutoshi Saito

Keyword(s):

Phase Transition ◽

Electron Microscope Study ◽

Room Temperature ◽

Hexagonal Lattice ◽

Ferroelectric Materials ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Periodic Arrays ◽

Modulation Wave Vector

BaZnGeO4 undergoes many phase transitions from I to V phase. The highest temperature phase I has a BaAl2O4 type structure with a hexagonal lattice. Recent X-ray diffraction study showed that the incommensurate (IC) lattice modulation appears along the c axis in the III and IV phases with a period of about 4c, and a commensurate (C) phase with a modulated period of 4c exists between the III and IV phases in the narrow temperature region (—58°C to —47°C on cooling), called the III' phase. The modulations in the IC phases are considered displacive type, but the detailed structures have not been studied. It is also not clear whether the modulation changes into periodic arrays of discommensurations (DC’s) near the III-III' and IV-V phase transition temperature as found in the ferroelectric materials such as Rb2ZnCl4.At room temperature (III phase) satellite reflections were seen around the fundamental reflections in a diffraction pattern (Fig.1) and they aligned along a certain direction deviated from the c* direction, which indicates that the modulation wave vector q tilts from the c* axis. The tilt angle is about 2 degree at room temperature and depends on temperature.

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Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

10.26434/chemrxiv.7092263.v1 ◽

2018 ◽

Author(s):

Katherine Marczenko ◽

James Goettel ◽

Gary Schrobilgen

Keyword(s):

Room Temperature ◽

Triphenylphosphine Oxide ◽

Donor Ligands ◽

Mechanical Shock ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination ◽

Xenon Trioxide ◽

Distorted Octahedra ◽

Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO3 was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, the solid [(C6H5)3PO]2XeO3, [(CH3)2SO]3(XeO3)2, and (C5H5NO)3(XeO3)2 adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are air-stable whereas [(CH3)2SO]3(XeO3)2 slowly decomposes over several days and [(CH3)2CO]3XeO3 undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C6H5)3PO]2XeO3 is a distorted square pyramid which provides the first example of a five-coordinate XeO3 adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO3. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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Effect of trytophan as dopant on potassium acid phthalate single crystals

10.31221/osf.io/cn28k ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Single Crystals ◽

Room Temperature ◽

Visible Region ◽

X Ray Diffraction ◽

X Ray ◽

Slow Evaporation Technique ◽

Absorption Studies ◽

Evaporation Technique ◽

Potassium Acid Phthalate ◽

Acid Phthalate

Optically transparent single crystals of potassium acid phthalate (KAP, 0.5 g) 0.05 g and 0.1 g (1 and 2 mol %) trytophan were grown in aqueous solution by slow evaporation technique at room temperature. Single crystal X- ray diffraction analysis confirmed the changes in the lattice parameters of the doped crystals. The presence of functional groups in the crystal lattice has been determined qualitatively by FTIR analysis. Optical absorption studies revealed that the doped crystals possess very low absorption in the entire visible region. The dielectric constant has been studied as a function of frequency for the doped crystals. The thermal stability was evaluated by TG-DSC analysis.

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Structural and Enhanced Optical Properties of Stabilized γ‒Bi2O3 Nanoparticles: Effect of Oxygen Ion Vacancies

Nanomaterials ◽

10.3390/nano10061023 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1023 ◽

Cited By ~ 2

Author(s):

Ashish Chhaganlal Gandhi ◽

Chia-Liang Cheng ◽

Sheng Yun Wu

Keyword(s):

Room Temperature ◽

Excess Oxygen ◽

Ambient Atmosphere ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Band Emission ◽

Oxygen Ion ◽

Integrated Intensity ◽

Effect Of Oxygen

We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.

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