ENHANCED UV EMISSION IN YTTRIUM-DOPED ZnS NANOPARTICLES SYNTHESIZED BY PRECIPITATION METHOD

2018 ◽  
Vol 25 (03) ◽  
pp. 1850063 ◽  
Author(s):  
NACHIMUTHU SUGANTHI ◽  
KUPPUSAMY PUSHPANATHAN
Keyword(s):  
Spherical Shape ◽  
Zinc Sulphide ◽  
Precipitation Method ◽  
Zns Nanoparticles ◽  
Ultraviolet Detector ◽  
Selected Area Electron Diffraction ◽  
Uv Emission ◽  
Zinc Blende ◽  
Transmission Electron ◽  
Photoluminescence Studies

This paper deals with the effect of yttrium doping on the structural and optical properties of zinc sulphide (ZnS) nanoparticles with nanoparticulated mesoporous. The morphology of the nanoparticles is determined by FESEM and it shows that the particles are spherical shape. HRSEM images show that particle size and agglomerated nature of the samples are augmented when doping concentration increases. Transmission electron microscope images probe the spherical shape of the nanoparticles as well as small number of inter particle mesoporous with intra-particles. The selected area electron diffraction images validate the crystalline and cubic nature of the synthesized samples. The presence of intra-particles is corroborated by XRD and FTIR spectra. X-ray diffraction’s results also confirm that the synthesized nanoparticles are crystallized in zinc blende structure. The diffuse reflectance spectra indicate that 5[Formula: see text]wt.% of yttrium-doped zinc sulphide shows higher reflectance than the undoped ZnS. Thus photoluminescence studies suggest that 5[Formula: see text]wt.% of yttrium-doped ZnS sample may be used for the development of supersensitive ultraviolet detector.

CONTROLLED SYNTHESIS AND CHARACTERIZATION OF CERIUM-DOPED ZnS NANOPARTICLES IN HMTA MATRIX

2011 ◽  
Vol 10 (03) ◽  
pp. 487-493 ◽  
Author(s):  
K. VIJAI ANAND ◽  
R. MOHAN ◽  
R. MOHAN KUMAR ◽  
M. KARL CHINNU ◽  
R. JAYAVEL
Keyword(s):  
Quantum Confinement Effect ◽  
Average Particle Size ◽  
Surface States ◽  
Deep Trap ◽  
Average Particle ◽  
Zns Nanoparticles ◽  
Selected Area Electron Diffraction ◽  
Luminescence Process ◽  
Photoluminescence Studies

Cerium-doped ZnS nanoparticles have been synthesized through hydrothermal method. The nanoparticles were stabilized using hexamethylenetetramine (HMTA) as surfactant in aqueous solution. The average particle size of the prepared samples is about 2 nm. The structure of the as-prepared ZnS nanoparticles is cubic (zinc blende) as demonstrated by X-ray powder diffraction (XRD) and selected area electron diffraction (SAED) analysis. TEM results showed that the synthesized nanoparticles were uniformly dispersed in the HMTA matrix without aggregation. The UV–Vis absorption spectra of the prepared ZnS nanoparticles show a considerable blueshift in the absorption band edge compared to bulk ZnS indicating a strong quantum confinement effect. Formation of HMTA-capped ZnS nanoparticles was confirmed by FTIR studies. Photoluminescence studies showed that the relative emission intensity of Ce3+ -doped ZnS nanoparticles is higher than that of undoped ZnS nanoparticles, which is due to the enhancement of radiative recombination in the luminescence process. The PL spectra showed two emission peaks at around 420 nm and 442 nm, which may be attributed to deep-trap emission or defect-related emission of ZnS and presence of various surface states.

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.

Synthesis and Characterization of Pure and Mn Doped Zinc Sulphide Nanoparticles and Nanofluids

2015 ◽  
Vol 1086 ◽  
pp. 101-106
Author(s):  
M. Gopalakrishnan ◽  
Issac P. Nelson ◽  
Solomon Jeevaraj A. Kingson
Keyword(s):  
Morphological Structure ◽  
Blue Shift ◽  
Chemical Precipitation ◽  
Zinc Sulphide ◽  
Precipitation Method ◽  
Average Particle ◽  
Zns Nanoparticles ◽  
Pure Zinc ◽  
Yellow Orange ◽  
Mn Doped

In this work, pure ZnS and Mn doped ZnS nanoparticles are synthesized by simple chemical precipitation method. The structure of pure zinc sulphide and Mn doped zinc sulphide sample are analyzed by X-ray diffraction technique. The morphological structure of zinc sulphide and Mn2+doped zinc sulphide nanoparticles are studied using scanning electron microscope (SEM). The average particle sizes of pure ZnS nanoparticles are determined to be from 29 nm to 44 nm and Mn doped ZnS nanoparticles are determined to be from 99 nm to 135 nm. The optical properties of pure and Mn doped ZnS nanoparticles have been investigated by photoluminescence (PL) spectroscopy. The emission spectrum of Mn2+doped with ZnS particles of the present study shows blue shift of the yellow-orange emission peak at 590 nm. Nanofluids are prepared for six different concentrations by dispersing pure and Mn2+doped ZnS nanoparticles in de-ionized water. Thermal conductivity studies are carried out for both nanofluid systems and the results are discussed.

Preparation of Monodisperse ColloidalZnONanoparticles and their Optical Properties

NANO ◽  
2015 ◽  
Vol 10 (05) ◽  
pp. 1550074 ◽  
Author(s):  
Chong Yang ◽  
Limei Tang ◽  
Qingsong Li ◽  
Ailing Bai ◽  
Yanqiu Wang ◽  
...  
Keyword(s):  
Zno Nanoparticles ◽  
Excess Oxygen ◽  
X Ray Diffraction ◽  
Red Emission ◽  
Selected Area Electron Diffraction ◽  
Uv Emission ◽  
Transmission Electron ◽  
High Resolution Tem ◽  
Uv Visible ◽  
Size Powder

Monodisperse colloidal zinc oxide ( ZnO ) nanospheres with a narrow size distribution were synthesized via a developed two-stage solution method. We controlled the size of the as-synthesized ZnO nanoparticles by varying the amount of ZnO /ethanol suspension added. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the diameter of the as-synthesized ZnO nanoparticles was in the range of 60–140 nm with a polydispersity index less than 5%. On high-resolution TEM images, we clearly observed that the ZnO nanospheres were actually composed of tiny ZnO subunits, several nanometers in size. Powder X-ray diffraction and TEM-selected area electron diffraction analysis showed that the spheres consisted of polycrystalline nanoparticles. The size of the subunits, which was confirmed by ultraviolet (UV)-visible spectroscopy, increased as the amount of ZnO /ethanol suspension added was decreased. A UV emission at about 374 nm was observed, and this emission of ZnO nanoparticles is found to depend on particle size due to the confinement effect. A red emission at about 651 nm, which has been reported for undoped ZnO , appeared due to the excess oxygen on the particles from O – H or C = O groups. The intensity of the red emission increased as the relative oxygen content increased. The formation mechanism of such ZnO nanospheres was also considered.

scholarly journals BIODEGRADABLE GELATIN DECORATED Fe3O4 NANOPARTICLES FOR PACLITAXEL DELIVERY

2018 ◽  
Vol 55 (1B) ◽  
pp. 7 ◽  
Author(s):  
Dai Hai Nguyen
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Drug Loading ◽  
Spherical Shape ◽  
Average Diameter ◽  
Precipitation Method ◽  
Loop Analysis ◽  
Transmission Electron ◽  
Potential Applications ◽  
Size And Morphology ◽  
Co Precipitation

The objective of this study is to prepare biodegradable iron oxide nanoparticles with gelatin (GEL) for paclitaxel (PTX) delivery. In detail, Fe3O4 nanoparticles were prepared and then coated them with GEL (Fe3O4@GEL) conjugate by co–precipitation method. Furthermore, the formation of Fe3O4@GEL was demonstrated by Fourier transform infrared (FT–IR) and powder X–ray diffraction (XRD). The superparamagnetic property of Fe3O4@GEL was also showed by hysteresis loop analysis, the saturation magnetization reached 20.36 emu.g–1. In addition, size and morphology of Fe3O4@GEL nanoparticles were determined by transmission electron microscopy (TEM). The results indicated that Fe3O4@GEL nanoparticles were spherical shape with average diameter of 10 nm. Especially, PTX was effectively loaded into the coated magnetic nanoparticles, 86.7 ± 3.2 % for drug loading efficiency and slowly released up to 5 days. These results suggest that the potential applications of Fe3O4@GEL nanoparticles in the development of stable drug delivery systems for cancer therapy.

Generation of ZnS Nanostructures with Modified Chemical Surface

MRS Advances ◽  
2019 ◽  
Vol 4 (38-39) ◽  
pp. 2095-2102 ◽  
Author(s):  
Josian Luciano Velázquez ◽  
Sonia J. Bailón-Ruiz
Keyword(s):  
Chemical Modification ◽  
Zinc Nitrate ◽  
Zinc Sulphide ◽  
Zns Nanoparticles ◽  
Negative Interaction ◽  
Chemical Surface ◽  
Interaction Studies ◽  
Transmission Electron ◽  
Potential Applications ◽  
Living Organisms

ABSTRACTSemiconductor nanomaterials like zinc sulphide have interesting potential applications, consequent to their size-dependent optical properties. These nanostructures can be used on optoelectronic, photocatalysis, solar cells, and fluorescence microscopy, among others. Due to the great use of these nanoparticles in society, there is great concern in the scientific community about the potential negative interaction of these nanomaterials in aquatic environments. The present research was conducted on generation of nanostructures of ZnS with modified surface. This work had three goals: 1) morphological, compositional, and optical characterization of ZnS nanoparticles; 2) surface chemical modification of ZnS nanoparticles with biocompatible molecules; and 3) interaction studies of ZnS nanoparticle. A main absorption peak at ∼365-375nm range and a trap emission peak at ∼425nm were observed in the emission spectrum of ZnS nanoparticles synthesized at 160°C and 180°C and 30 minutes of reaction. The morphology and the size of ZnS were carried out by High Resolution Transmission Electron Microscopy (HR-TEM). In this way, nanoparticles were spherical and with a size less than 10nm. Energy Dispersive X-Ray Spectroscopy evidenced the chemical composition of produced nanostructures. The chemical modification of ZnS nanostructures was corroborated by Infrared Spectroscopy Analysis. The interaction studies of ZnS nanoparticles were studied in aquatic systems in presence of marine organisms. The concentrations of nanoparticles for these studies ranged from 0ppm to 300ppm and the contacting time with the living organisms was 24 and 48 hours. Also, Zn2+ (as Zinc nitrate and Zinc sulphate) was used as comparison purposes. Zinc sulphide nanoparticles covered with thioglycolic acid and L-cysteine evidenced a negative interaction at concentrations higher than 10ppm.

PHOTOLUMINESCENCE SPECTRA AND MAGNETIC PROPERTIES OF HYDROTHERMALLY SYNTHESIZED MnO2 NANORODS

2013 ◽  
Vol 27 (29) ◽  
pp. 1350211 ◽  
Author(s):  
ARBAB MOHAMMAD TOUFIQ ◽  
FENGPING WANG ◽  
QURAT-UL-AIN JAVED ◽  
QUANSHUI LI ◽  
YAN LI
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Room Temperature ◽  
Blue Emission ◽  
Green Emission ◽  
X Ray Diffraction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Uv Emission ◽  
Transmission Electron

In this paper, single crystalline tetragonal MnO 2 nanorods have been synthesized by a simple hydrothermal method using MnSO 4⋅ H 2 O and Na 2 S 2 O 8 as precursors. The crystalline phase, morphology, particle sizes and component of the as-prepared nanomaterial were characterized by employing X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and energy-dispersive X-ray spectroscopy (EDS). The photoluminescence (PL) emission spectrum of MnO 2 nanorods at room temperature exhibited a strong ultraviolet (UV) emission band at 380 nm, a prominent blue emission peak at 453 nm as well as a weak defect related green emission at 553 nm. Magnetization (M) as a function of applied magnetic field (H) curve showed that MnO 2 nanowires exhibited a superparamagnetic behavior at room temperature which shows the promise of synthesized MnO 2 nanorods for applications in ferrofluids and the contrast agents for magnetic resonance imaging. The magnetization versus temperature curve of the as-obtained MnO 2 nanorods shows that the Néel transition temperature is 94 K.

Structure of CdS Films Deposited on Single-Crystal Substrates

1968 ◽  
Vol 26 ◽  
pp. 406-407
Author(s):  
G. Shimaoka
Keyword(s):  
Electron Diffraction ◽  
Single Crystal ◽  
Marked Effect ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Zinc Blende ◽  
Transmission Electron ◽  
Deposited Films ◽  
Reflection Electron Diffraction ◽  
Cds Films

Recent X-ray or electron diffraction studies of CdS films vacuum-deposited on single-crystal substrates, such as mica, rock salt, etc., have demonstrated a marked effect of the substrate on the structure and orientation of the deposited films, particularly Escoffery has reported that cubic CdS (zinc-blende type) could be produced on molybdenum foil heated at 175°C. The purpose of this study is to investigate structure and orientation of thin CdS films evaporated onto various single-crystal substrates having hexagonal or cubic structure as a function of substrate temperature and to find optimum epitaxial growth condition.Single-crystal CdS (hexagonal, wurtzite type) was evaporated onto freshly cleaved (0001) MoS2, (111) CaF2 and (100) NaCl surfaces heated at various temperatures between ∼25° and 500°C in a vacuum of about 5 x 10-5 Torr. Average thickness of the deposited films was about 100Å. The rate of deposition was about 2Å/sec. The deposited films were examined by three different methods: a) reflection electron diffraction, b) high-resolution transmission electron diffraction and c) transmission electron microscopy and selected-area electron diffraction.

Synthesis, optical and structural characterisation of ZnS nanoparticles derived from Zn(ii) dithiocarbamate complexes

2021 ◽  
Vol 19 (1) ◽  
pp. 1134-1147
Author(s):  
Damian C. Onwudiwe ◽  
Jerry O. Adeyemi ◽  
Rebecca T. Papane ◽  
Felicia F. Bobinihi ◽  
Eric Hosten
Keyword(s):  
Blue Shift ◽  
Zinc Sulphide ◽  
Bandgap Energy ◽  
Spectroscopic Techniques ◽  
Zns Nanoparticles ◽  
Structural Characterisation ◽  
Trigonal Bipyramidal ◽  
Transmission Electron ◽  
Trigonal Prismatic ◽  
Distorted Trigonal Bipyramidal

Abstract Zinc sulphide nanoparticles represented as ZnS1, ZnS2 and ZnS3 have been prepared from Zn(ii) N-methyl-N-ethanoldithiocarbamate (1) complex and its 2,2′-bipyridine (2) and 1,10′-phenanthroline (3) adducts, respectively. Both the parent complex (1) and the adducts (2) and (3) were characterised by spectroscopic techniques and elemental analysis. In the solid state, the structures of complexes (1) and (2) were established using single-crystal X-ray analysis. Complex (1) possessed a distorted trigonal bipyramidal geometry about the zinc centre, whilst forming a dimer via bidentate bridging coordination between two opposite dithiocarbamate motifs. On the other hand, complex (2) formed a trigonal prismatic geometry about the Zn centre with a ZnS4N2 chromophore. The decomposition of the complexes in hexadecylamine afforded spherical-shaped ZnS nanoparticles of the cubic sphalerite crystal phase. The transmission electron microscopy (TEM) micrographs showed that the average particles size of ZnS1, ZnS2 and ZnS3 were 2.63, 5.27 and 6.52 nm, respectively. In the optical study, the estimated bandgap energies were found in the range between 4.34 and 4.08 eV, which indicated a blue shift when compared with the bandgap energy of bulk ZnS.

Synthesis and Luminescent Behavior of Mn(1-X)S:AX/ZnS Core/Shell Nanocrystals

2011 ◽  
Vol 335-336 ◽  
pp. 669-673
Author(s):  
Li Hua Li ◽  
Yong Jun Gu ◽  
Rui Shi Xie ◽  
Jian Guo Zhu
Keyword(s):  
Surface Passivation ◽  
Spherical Shape ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Nonradiative Recombination ◽  
X Ray Diffraction ◽  
Enhanced Photoluminescence ◽  
Transmission Electron ◽  
Average Grain Size ◽  
Zns Nanocrystals

Mn(1-X)S:AX/ZnS (A: Er, Dy) nanocrystals were synthesized by chemical precipitation method. X-ray diffraction analysis show that Mn(1-X)S:AX/ZnS nanocrystals were zincblende structure. The high-resolution transmission electron microscope images indicated that Mn(1-X)S:AX/ZnS nanocrystals show a spherical shape, and their average grain size is about 4 nm. Photoluminescence spectra of Mn(1-X)S:AX/ZnS nanocrystals revealed that there existed several major emission bands, ～417 nm, ~509 nm, ~580 nm, ~617nm and ~680 nm. Mn(1-X)S:AX/ZnS nanocrystals exhibited enhanced luminescence properties compared with the pure Mn(1-X)S:AX nanocrystals. The enhanced photoluminescence properties of Mn(1-X)S:AX/ZnS nanocrystals should be attributed to the effective suppression of nonradiative recombination by the surface-passivation layer.

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