scholarly journals Effect of Annealing on the ZnS Nanocrystals Prepared by Chemical Precipitation Method

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Nadana Shanmugam ◽  
Shanmugam Cholan ◽  
Natesan Kannadasan ◽  
Kannadasan Sathishkumar ◽  
G. Viruthagiri
Keyword(s):  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
Atomic Force ◽  
Transmission Electron ◽  
Different Temperatures ◽  
Uv Visible ◽  
Dta Curves

Nanocrystals of ZnS have been synthesized through simple chemical precipitation method using thiourea as sulphur source. The synthesized products were annealed at different temperatures in the range of 200–800∘C. The as-synthesized and annealed samples were characterized by X-ray diffraction (XRD), UV-Visible absorption (UV-Vis), and room temperature photoluminescence (PL) measurements. The morphological features of ZnS annealed at 200 and 500∘C were studied by atomic force microscope (AFM) and transmission electron microscope (TEM) techniques. The phase transformation of ZnS and formation of ZnO were confirmed by thermogravimetric (TG) and differential thermal analysis (DTA) curves.

Synthesis and photocatalytic properties of magnetic separable and recyclable p-n heterojunction CoFe2O4/Bi12O17Cl2 photocatalyst

CrystEngComm ◽  
2021 ◽  
Author(s):  
Kexin Fang ◽  
Lei Shi ◽  
Lishuang Cui ◽  
Chunwei Shi ◽  
Weiwei Si
Keyword(s):  
Chemical Precipitation ◽  
Photocatalytic Properties ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Crystallinity

A series of CoFe2O4/Bi12O17Cl2 (CFO/Bi12O17Cl2) nanocomposites have been prepared by chemical precipitation method. The result of X-ray diffraction showed that CFO/Bi12O17Cl2 composites had high crystallinity. It was found that CoFe2O4...

Monodisperse Fe3O4/Fe Core/Shell Nanoparticles with Enhanced Magnetic Property

2011 ◽  
Vol 306-307 ◽  
pp. 410-415
Author(s):  
Li Sun ◽  
Fu Tian Liu ◽  
Qi Hui Jiang ◽  
Xiu Xiu Chen ◽  
Ping Yang
Keyword(s):  
Average Diameter ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Core Shell ◽  
X Ray Diffraction ◽  
Shell Nanoparticles ◽  
X Ray ◽  
Transmission Electron ◽  
Shell Particles ◽  
Core Shell Nanoparticles

Core/shell type nanoparticles with an average diameter of 20nm were synthesized by chemical precipitation method. Firstly, Monodisperse Fe3O4 nanoparticles were synthesized by solvethermal method. FeSO4ž7H2O and NaBH4 were respectively dissolved in distilled water, then moderated Fe3O4 particles and surfactant(PVP) were ultrasonic dispersed into the FeSO4ž7H2O solution. The resulting solution was stirred 2 h at room temperature. Fe could be deposited on the surface of monodispersed Fe3O4 nanoparticles to form core-shell particles. The particles were characterized by using various experimental techniques, such as transmission electron microscopy (TEM), X-ray diffraction (XRD), AGM and DTA. The results suggest that the saturation magnetization of the nanocomposites is 100 emu/g. The composition of the samples show monodisperse and the sides of the core/shell nanoparticles are 20-30nm. It is noted that the formation of Fe3O4/Fe nanocomposites magnetite nanoparticles possess superparamagnetic property.

scholarly journals Preparation of Fe-DopedTiO2Nanotubes and Their Photocatalytic Activities under Visible Light

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Honghui Teng ◽  
Shukun Xu ◽  
Dandan Sun ◽  
Ying Zhang
Keyword(s):  
Visible Light ◽  
Visible Region ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Ultrasonic Assisted ◽  
Uv Visible

Fe-doped TiO2nanotubes (Fe-TNTs) have been prepared by ultrasonic-assisted hydrothermal method. The structure and composition of the as-prepared TiO2nanotubes were characterized by transmission electron microscopy, X-ray diffraction, and UV-Visible absorption spectroscopy. Their photocatalytic activities were evaluated by the degradation of MO under visible light. The UV-visible absorption spectra of the Fe-TNT showed a red shift and an enhancement of the absorption in the visible region compared to the pure TNT. The Fe-TNTs were provided with good photocatalytic activities and photostability and under visible light irradiation, and the optimum molar ratio of Ti : Fe was found to be 100 : 1 in our experiments.

Mixed-Solvothermal Preparation of Mace-Like CdS Nanocrystals

2012 ◽  
Vol 502 ◽  
pp. 164-168
Author(s):  
Ling Xu ◽  
Han Mei Hu ◽  
Hai Yan Xu
Keyword(s):  
Electron Microscopy ◽  
Large Scale ◽  
Volume Ratio ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Cds Nanostructures ◽  
Uv Visible ◽  
Solvothermal Preparation

Novel mace-like (wolf-teeth clubs) CdS nanostructures were successfully prepared on a large scale using CdCl2•2.5H2O and NH2CSNH2 as starting materials through a convenient mixed-solvothermal route. The as-synthesized products were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-visible absorption spectroscopy. The experimental results reveal that the morphology of CdS products was greatly affected by the volume ratio of anhydrous ethanol and distilled water. The possible mechanism for the formation of mace-like CdS nanostructures is simply discussed.

Synthesis of RePO4 (Re=La, Nd, Pr, or Y) Nanowires by Chemical Precipitation in Nanochannels

2011 ◽  
Vol 181-182 ◽  
pp. 495-500 ◽  
Author(s):  
Cheng Mu ◽  
Jun Hui He
Keyword(s):  
Rare Earth ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Aao Template ◽  
Sem Images ◽  
Transmission Electron ◽  
Rare Earth Phosphate ◽  
Xrd Patterns ◽  
Uniform Diameter

Monodisperse nanowires of rare earth phosphates were synthesized by chemical precipitation method using anodic aluminum oxide (AAO) template. Scanning electron microscope (SEM) images indicated that rare earth phosphate nanowires are parallelly arranged in AAO template, all of which are in uniform diameter of about 50 nm. X-ray diffraction (XRD) patterns and high magnification transmission electron microscopy (HRTEM) images showed that the nanowires were polycrystal structure.

Fluorescence Enhancement of ZnS Nanocrystals via Ultraviolet Irradiation

2014 ◽  
Vol 556-562 ◽  
pp. 27-31
Author(s):  
Ling Ling Peng ◽  
Bi Tao Liu ◽  
Tao Han
Keyword(s):  
Ultraviolet Irradiation ◽  
Surface Defects ◽  
Irradiation Time ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Photoluminescence Intensity ◽  
X Ray Diffraction ◽  
Zinc Blende ◽  
Transmission Electron ◽  
Zns Nanocrystals

ZnS nanocrystals were prepared via chemical precipitation method and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectra. The results indicated that the ZnS nanocrystals have cubic zinc blende structure and diameter is 3.68 nm as demonstrated by XRD. The morphology of nanocrystals is spherical measured by TEM which shows the similar particle size. The photoluminescence spectrum peaking at about 424 nm was due mostly to the trap-state emission, and a satellite peak at 480nm ascribed to the dangling bond of S in the surface of ZnS nanocrystals. The emission intensity of ZnS was enhanced after ultraviolet irradiation, the enhancement of the Photoluminescence intensity was due to the elimination of the surface defects after ultraviolet irradiation, for the growth of the coated shell on ZnS nonacrystals, the Photoluminescence intensity was increased as ultraviolet irradiation time growth, finally tends to be stable for the surface state of nanocrystals steady.

scholarly journals Synthesis and characterization of ZnTe nanoparticles

2016 ◽  
Vol 17 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Sujan Dhungana ◽  
Bhoj Raj Paudel ◽  
Surendra K. Gautam
Keyword(s):  
Particle Size ◽  
Field Effect Transistors ◽  
Average Particle Size ◽  
Precursor Solution ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Zinc Compounds ◽  
Transmission Electron

In this work, we report the ZnTe semiconductor nanoparticles (NPs) prepared by aqueous chemical precipitation method using the tellurium precursor solution with different zinc compounds. Three batches of ZnTe NPs were synthesized to study the effect of dilution on the size and phase purity of ZnTe. The influence of source compounds and concentrations of the size and structure of NPs were studied. ZnTe NPs have great applications as field-effect transistors and photodetectors. The existing controversy regarding the crystalline structure of ZnTe NPs, whether it is cubic or hexagonal, has been resolved using X-ray Diffraction (XRD) data. The ZnTe NPs possess cubic structure, which is also confirmed by Electron Diffraction (ED) pattern. The average particle size determined from XRD data with the help of Debye-Scherrer equation is about 6 nm. The particle size can be further verified by Transmission Electron Microscopy (TEM) studies.  

scholarly journals Conductivity Research on ABS & PC Converted Core Shell Quantum Dot Doped in ABS & PC

2019 ◽  
Vol 8 (4) ◽  
pp. 7740-7742
Keyword(s):  
Quantum Dot ◽  
Core Shell ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Wet Chemical ◽  
Uv Visible ◽  
Lcr Meter ◽  
Absorption Characteristics

Zns: Mn / ZnO inverted shell quantum dots have been synthesized using a wet chemical process.The study used Mn of 4 percent weight. Transmission Electron Microscope (TEM) images show a 50 nm order for the quantum dot size. Confirmation of the ZnO capped ZnSMn was done by TEM and X ray diffraction (XRD).The test band distance is measured using the UV Visible absorption characteristics. Measurement of the dielectric constant is done using the LCR meter

Morphology, Opto-Electronic and Dielectric Properties of Vacuum Sublimed CuPc Based Thin Films

2019 ◽  
Vol 14 (11) ◽  
pp. 1523-1531
Author(s):  
Manjit Kaur ◽  
Rakesh Dogra ◽  
Narinder Arora ◽  
Navjeet Sharma ◽  
Rajesh Kumar
Keyword(s):  
Thin Films ◽  
Hole Mobility ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Optical Band Gaps ◽  
Different Temperatures ◽  
Evaporation Technique ◽  
Uv Visible ◽  
Substrate Temperatures

AC transport properties and dielectric response of sandwich geometry (Ag/CuPc/Ag) of CuPc(CuPc) thin films deposited using thermal evaporation technique have been studied within frequency range 1 Hz–10 KHz and in temperature range 303–383 K. Scanning electron microscope (SEM) investigations of these films reveal fiber like morphology. Crystalline natures of CuPc films have been characterized using X-ray diffraction for different temperatures. The molecular orientations in films for different substrate temperatures have been confirmed by Raman spectroscopy. The optical band gaps calculated from the UV–Visible absorption spectra is found to lie in the range 3.01–3.15 eV. Electrical conductivity of CuPc films increases with increase of temperature. The hole mobility values of CuPc films at different temperatures have been calculated using negative differential susceptance (–ΔB) technique. Both capacitance and dielectric constant have been found to decrease with the increase of frequency and temperature.

scholarly journals Synthesis and Characterization of Cysteine-Capped CdSe Nanoparticles Using an Alternative of Selenium

2019 ◽  
Vol 31 (11) ◽  
pp. 2457-2460
Author(s):  
K.E. Mokubung ◽  
M.J. Moloto ◽  
K.P. Mubiayi ◽  
N. Moloto
Keyword(s):  
Cdse Nanoparticles ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Tem Analysis ◽  
Visible Absorption ◽  
Prepared Nanoparticles ◽  
Transmission Electron ◽  
Different Temperatures ◽  
Xrd Patterns ◽  
Average Size

Present work reports synthesis of L-cysteine capped CdSe nanoparticles at different temperatures via an aqueous medium, non-toxic and green colloidal route. Cadmium chloride (CdCl2·5H2O) and sodium selenite (Na2SeO3) were used as cadmium and selenium sources respectively. The prepared nanoparticles are characterized by UV-visible absorption and photoluminescence spectroscopy, Fourier transform infrared, X-ray diffraction and transmission electron microscopy. The XRD patterns confirm a cubic phase structure of the prepared nanoparticles at 55, 75 and 95 ºC, respectively. The TEM analysis, optical absorption and photoluminescence spectra shows epitaxial growth of CdSe nanoparticles as the temperature increases with average size diameter of 4.12 ± 0.32, 5.02 ± 0.234 and 5.53 ± 0.321 nm for 55, 75 and 95 ºC, respectively.

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