scholarly journals Electrospinning Synthesis of Fe3O4/Eu(DBM)3phen/PVP Multifunctional Microfibers and Their Structure, Luminescent and Magnetic properties

2021 ◽  
Author(s):  
Ruifei Qin ◽  
lina liu
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Electrospinning Process ◽  
Europium Complex ◽  
X Ray Diffraction ◽  
Excitation Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
Average Size

Abstract Multifunctional Fe3O4/Eu(DBM)3phen/PVP ((DBM: dibenzoylmethane, phen: 1,10-phenanthroline, PVP: polyvinyl pyrrolidone) microfibers were constructed by simple electrospinning process. The structure and morphology of the microfibers were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. The diameters of pure PVP microfibers and the microfibers doped only with Fe3O4 nanoparticles (NPs) were uniformly distributed, with an average size of about 360 nm. When 3% Eu(DBM)3phen complex and Fe3O4 NPs were both added to the precursor for electrospinning, the microfibers became very inhomogeneous in diameter. The photoluminescent properties of pure Eu(DBM)3phen complex and composite microfibers were also studied. The characteristic emission peaks of Eu3+ appeared in the composite microfibers. The intensities of emission and excitation spectra gradually decrease with adding more Fe3O4 NPs. The unit mass of the pure europium complex in some composite microfibers gave stronger luminescence than the pure europium complex. The fluorescence lifetime of 5D0 state in the composite microfibers is longer than that of pure europium complex. Additionally, the magnetic properties of Fe3O4 NPs and the composite microfibers were investigated. Fe3O4 NPs and composite microfibers were both superparamagnetic. The saturation magnetization of the composite microfibers was smaller than that of pure Fe3O4 NPs.

scholarly journals Formation of ZnO/Zn0.5Cd0.5Se Alloy Quantum Dots in the Presence of High Oleylamine Contents

Nanomaterials ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 999
Author(s):  
Yi-An Chen ◽  
Kuo-Hsien Chou ◽  
Yi-Yang Kuo ◽  
Cheng-Ye Wu ◽  
Po-Wen Hsiao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Quantum Dots ◽  
Particle Size ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Alloy Quantum Dots ◽  
First Time

To the best of our knowledge, this report presents, for the first time, the schematic of the possible chemical reaction for a one-pot synthesis of Zn0.5Cd0.5Se alloy quantum dots (QDs) in the presence of low/high oleylamine (OLA) contents. For high OLA contents, high-resolution transmission electron microscopy (HRTEM) results showed that the average size of Zn0.5Cd0.5Se increases significantly from 4 to 9 nm with an increasing OLA content from 4 to 10 mL. First, [Zn(OAc)2]–OLA complex can be formed by a reaction between Zn(OAc)2 and OLA. Then, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) data confirmed that ZnO is formed by thermal decomposition of the [Zn(OAc)2]–OLA complex. The results indicated that ZnO grew on the Zn0.5Cd0.5Se surface, thus increasing the particle size. For low OLA contents, HRTEM images were used to estimate the average sizes of the Zn0.5Cd0.5Se alloy QDs, which were approximately 8, 6, and 4 nm with OLA loadings of 0, 2, and 4 mL, respectively. We found that Zn(OAc)2 and OLA could form a [Zn(OAc)2]–OLA complex, which inhibited the growth of the Zn0.5Cd0.5Se alloy QDs, due to the decreasing reaction between Zn(oleic acid)2 and Se2−, which led to a decrease in particle size.

TEM Study of FePt and FePt:C/FePt Composite Double-Layered Thin Films

2013 ◽  
Vol 275-277 ◽  
pp. 1952-1955
Author(s):  
Ling Fang Jin ◽  
Xing Zhong Li
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Grain Size ◽  
Magnetic Properties ◽  
Composite Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

New functional nanocomposite FePt:C thin films with FePt underlayers were synthesized by noneptaxial growth. The effect of the FePt layer on the ordering, orientation and magnetic properties of the composite layer has been investigated by adjusting FePt underlayer thickness from 2 nm to 14 nm. Transmission electron microscopy (TEM), together with x-ray diffraction (XRD), has been used to check the growth of the double-layered films and to study the microstructure, including the grain size, shape, orientation and distribution. XRD scans reveal that the orientation of the films was dependent on FePt underlayer thickness. In this paper, the TEM studies of both single-layered nonepitaxially grown FePt and FePt:C composite L10 phase and double-layered deposition FePt:C/FePt are presented.

EFFECT OF NANOCRYSTALLIZATION ANNEALING ON MAGNETIC PROPERTIES AND MAGNETOIMPEDANCE OF CO-BASE RIBBONS

2012 ◽  
Vol 05 ◽  
pp. 841-846
Author(s):  
AMIR KEYVANARA ◽  
REZA GHOLAMIPOUR ◽  
SHAMSEDIN MIRDAMADI ◽  
FARZAD SHAHRI ◽  
HOSSEIN SEPEHRI AMIN
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Magnetic Properties ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Melt Spun ◽  
Melt Spun Ribbons ◽  
Nanocrystalline Phases

Melt spun ribbons of Co 64 Fe 4 Ni 2 B 19 Si 8 Cr 3 alloy have been prepared and the nanocrystallization process was carried out by the heat treatment of the as spun ribbons above the crystallization temperature. Structural studies of the samples have been performed by transmission electron microscopy and X-ray diffraction. Magnetic properties of the samples and magnetoimpedance measurements were investigated and it was revealed that magnetic properties and magnetoimpedance of the samples deteriorate by the formation of nanocrystalline phases.

Preparation, Characterization and Spectroscopy of Eu3+ in Gd2O3 Nanorods

2008 ◽  
Vol 8 (3) ◽  
pp. 1398-1403 ◽  
Author(s):  
Liqin Liu ◽  
En Ma ◽  
Renfu Li ◽  
Xueyuan Chen
Keyword(s):  
Electron Microscopy ◽  
Fluorescence Spectra ◽  
Filling Factor ◽  
Energy Levels ◽  
Diffraction Field ◽  
X Ray Diffraction ◽  
Excitation Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Eu3+:Gd2O3 nanorods were prepared by a hydrothermal method. X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and Fourier transform-infrared spectroscopy were used to characterize the resulting samples. Emission and excitation spectra were studied using xenon excited spectroscopic experiments at 10 K. Energy transfer from Gd3+ to Eu3+, from the band gap of the host to Eu3+, and from Eu3+ (S6) to Eu3+ (C2) was observed. The energy levels of Eu3+ at the C2 site of cubic Gd2O3 were experimentally determined according to the fluorescence spectra at 10 K, and fit well with the theoretical values. The standard deviation for the optimal fit was 12.9 cm−1. The fluorescent lifetime of 5D0 (2.3 ms at 295 K) was unusually longer than that of the bulk counterparts (0.94 ms), indicating a small filling factor (0.55) for the nanorod volume. However the lifetime of 5D1 was much shorter than that of the bulk counterparts, 65 μs at 10 K, 37 μs at 295 K.

Fine Tuning Magnetic Properties of FePt:C Thin Films by FePt UnderLayers

2013 ◽  
Vol 313-314 ◽  
pp. 254-257
Author(s):  
Ling Fang Jin ◽  
Hong Zhuang
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Magnetic Properties ◽  
Fine Tuning ◽  
Nanocomposite Films ◽  
Nanocomposite Thin Film ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Nonepitaxially grown FePt (x)/FePt:C thin films were synthesized, where FePt (x) (x=2, 5, 8, 11, 14 nm) layers were served as underlayers and FePt:C layer was nanocomposite with thickness of 5 nm. The effect of FePt underlayer on the ordering, orientation and magnetic properties of FePt:C thin films has been investigated by adjusting FePt underlayer thicknesses from 2 nm to 14 nm. X-ray diffraction (XRD), together with transmission electron microscopy (TEM) confirmed that the desired L10 phase was formed and films were (001) textured with FePt underlayer thickness decreased less 5 nm. For 5 nm FePt:C nanocomposite thin film with 2 nm FePt underlayer, the coercivity was 8.2 KOe and the correlation length of FePt:C nanocomposite film was 67 nm. These results reveal that the better orientation and magnetic properties for FePt:C nanocomposite films can be tuned by decreasing FePt underlayer thickness.

Research on Structural Properties of FePt: C Thin Films with FePt Underlayers

2013 ◽  
Vol 385-386 ◽  
pp. 7-10
Author(s):  
Ling Fang Jin ◽  
Hong Zhuang
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Magnetic Properties ◽  
Structural Properties ◽  
Composite Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Nonepitaxially grown double-layered films were synthesized with a FePt: C composite layer on top of continuous FePt underlayer. The thickness of FePt was changed from 2 nm to 14 nm. Nanostructures, crystalline orientations and the effect of FePt underlayer on the ordering, orientation and magnetic properties of the thin films were investigated by transmission electron microscopy (TEM) and x-ray diffraction (XRD). XRD confirmed the formation of the ordered L10phase for 5 nm FePt: C film with FePt thickness decreased to 5 nm. TEM studies of FePt:C composite L10phase and double-layered deposition FePt:C/FePt were presented.

scholarly journals Synthesis of Flower-Like Cu2ZnSnS4Nanoflakes via a Microwave-Assisted Solvothermal Route

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Fei Long ◽  
Shuyi Mo ◽  
Yan Zeng ◽  
Shangsen Chi ◽  
Zhengguang Zou
Keyword(s):  
Electron Microscopy ◽  
Raman Scattering ◽  
Zinc Acetate Dihydrate ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Direct Band ◽  
Xrd Patterns ◽  
Average Size

Flower-like Cu2ZnSnS4(CZTS) nanoflakes were synthesized by a facile and fast one-pot solution reaction using copper(II) acetate monohydrate, zinc acetate dihydrate, tin(IV) chloride pentahydrate, and thiourea as starting materials. The as-synthesized samples were characterized by X-ray diffraction (XRD), Raman scattering analysis, field emission scanning electron microscopy (FESEM) equipped with an energy dispersion X-ray spectrometer (EDS), transmission electron microscopy (TEM), and UV-Vis absorption spectra. The XRD patterns shown that the as-synthesized particles were kesterite CZTS and Raman scattering analysis and EDS confirmed that kesterite CZTS was the only phase of product. The results of FESEM and TEM show that the as-synthesized particles were flower-like morphology with the average size of 1~2 μm which are composed of 50 nm thick nanoflakes. UV-Vis absorption spectrum revealed CZTS nanoflakes with a direct band gap of 1.52 eV.

Synthesis and Luminescence Properties of Yb3+/Ho3+ Co-Doped Lu2O3 Nanocrystalline Powders

2007 ◽  
Vol 280-283 ◽  
pp. 521-524
Author(s):  
Li Qiong An ◽  
Jian Zhang ◽  
Min Liu ◽  
Sheng Wu Wang
Keyword(s):  
Electron Microscopy ◽  
Upconversion Luminescence ◽  
Nanocrystalline Powders ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Excitation Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Co Precipitation ◽  
Co Doped

Yb3+ and Ho3+ co-doped Lu2O3 nanocrystalline powders were synthesized by a reversestrike co-precipitation method. The as-prepared powders were examined by the X-ray diffraction and transmission electron microscopy. The phase composition of the powders was cubic and the particle size was in the range of 30~50 nm. Emission and excitation spectra of the powders were measured by a spectrofluorometer and the possible upconversion luminescence mechanism was also discussed.

Receiving Copper Nanoparticles: Experiment and Modelling

2019 ◽  
Vol 288 ◽  
pp. 140-147 ◽  
Author(s):  
Andrey V. Nomoev ◽  
Erzhena C. Khartaeva ◽  
Natalia V. Yumozhapova ◽  
Tumen G. Darmaev ◽  
S.P. Bardakhanov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Copper Nanoparticles ◽  
Pure Copper ◽  
Current Strength ◽  
X Ray Diffraction ◽  
X Ray ◽  
Embedded Atom ◽  
Transmission Electron ◽  
Average Size

The copper nanoparticles were obtained by evaporating the metal by the relativistic electron beam. The average size of synthesized particles was about 120 nm. They were characterized by X-ray diffraction, transmission electron microscopy. The results of the X-ray diffraction showed high content of the pure copper for closed setup with an inert gas. Transmission electron microscopy cleared some particles to have an icosahedral structure. These nanoparticles were obtained when the target was exposed by the beam with the highest current strength used in the experiment and the highest cooling of the copper vapor. The process of copper nanoparticle formation by the molecular dynamic method using EAM – potentials (potentials in the Embedded Atom Method form) was studied.

scholarly journals Fabrication and magnetic properties of hierarchical nickel microwires with nanothorns

2010 ◽  
Vol 8 (2) ◽  
pp. 434-439 ◽  
Author(s):  
Junhao Zhang ◽  
Ling Yang ◽  
Xiaofang Cheng ◽  
Jinmeng Zhang ◽  
Fucai Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Cooperative Effect ◽  
Magnetic Interactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

AbstractHierarchical nickel microwires with nanothorns were fabricated through a reduction of nickelous salt with hydrazine in diethanolamine. The product was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). The growth mechanism of the nickel microwires with nanothorns is proposed, based on the evolution of the structures and morphologies, which could be ascribed to the cooperative effect of the complexant of diethanolamine and inherent magnetic interactions. Magnetic properties of the product were measured at room temperature and compared with other shaped counterparts.

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