scholarly journals Ecotoxicological Studies of ZnO and CdS Nanoparticles on Chlorella vulgaris Photosynthetic Microorganism in Seine River Water

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 227 ◽  
Author(s):  
Alice da Rocha ◽  
Nicolas Menguy ◽  
Claude Yéprémian ◽  
Alain Couté ◽  
Roberta Brayner
Keyword(s):  
River Water ◽  
Chlorella Vulgaris ◽  
Cds Nanoparticles ◽  
Seine River ◽  
X Ray ◽  
Atp Assay ◽  
Transmission Electron ◽  
Activity Measurements ◽  
Biological Target ◽  
Photosynthetic Microorganism

Seine river water was used as natural environmental medium to study the ecotoxicological impact of ZnO and CdS nanoparticles and Zn2+ and Cd2+ free ions using Chlorella vulgaris as a biological target. It was demonstrated by viability tests and photosynthetic activity measurements that free Zn2+ (IC50 = 2.7 × 10−4 M) is less toxic than free Cd2+ and ZnO nanoparticles (IC50 = 1.4 × 10−4 M). In the case of cadmium species, free Cd2+ (IC50 = 3.5 × 10−5 M) was similar to CdS nanoparticles (CdS-1: IC50 = 1.9 × 10−5 M and CdS-2: IC50 = 1.9 × 10−5 M), as follows: CdS > Cd2+ > ZnO > Zn2+. Adenosine-5’-triphosphate (ATP) assay and superoxide dismutase (SOD) enzymatic activity confirmed these results. Transmission electron microscopy (TEM), coupled with energy-dispersive X-ray spectroscopy (EDS), confirmed the internalization of CdS-1 nanoparticles after 48 h of contact with Chlorella vulgaris at 10−3 M. With a higher concentration of nanoparticles (10−2 M), ZnO and CdS-2 were also localized inside cells.

PREPARATION OF CUBE-SHAPED CdS NANOPARTICLES BY SONOCHEMICAL METHOD

2002 ◽  
Vol 01 (05n06) ◽  
pp. 437-441 ◽  
Author(s):  
HUI WANG ◽  
YINONG LU ◽  
JUNJIE ZHU
Keyword(s):  
Ultrasound Irradiation ◽  
Nucleation And Growth ◽  
Cds Nanoparticles ◽  
Microemulsion System ◽  
Sonochemical Method ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Oil In Water ◽  
Uv Visible

Cube-shaped CdS nanoparticles have been successfully prepared by a sonochemical method in an oil-in-water microemulsion. The product was characterized by using techniques including X-ray powder diffraction, high-resolution transmission electron microscopy, energy-dispersive X-ray analysis and UV-visible absorption spectroscopy. This microemulsion system in the presence of high-intensity ultrasound irradiation provides special conditions for the nucleation and growth of the CdS nanoparticles.

scholarly journals Fabrication, characterization and photocatalytic properties of CdS nanoparticles modified by N-doped TiO2 NTs

2018 ◽  
Vol 36 (3) ◽  
pp. 348-353
Author(s):  
Dawei Gao ◽  
Chunxia Wang ◽  
Yu Jian ◽  
Weiwei Li ◽  
Pengyu Dong
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Emission Spectra ◽  
Photocatalytic Properties ◽  
Cds Nanoparticles ◽  
Nanotube Arrays ◽  
X Ray ◽  
Transmission Electron

AbstractHighly ordered TiO2 nanotube arrays (TiO2 NTs) were prepared by anodic oxidizing method on a surface of Ti substrate. Fabrication of nitrogen-doped TiO2 nanotube arrays (N-TiO2 NTs) was carried out by immersion in ammonia solution. CdS nanoparticles loaded N-doped TiO2 nanotube arrays (CdS/N-TiO2 NTs) were obtained by successive ionic layer adsorption and reaction (SILAR) technique. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), photoluminescence (PL) emission spectra and ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy (DRS). The results indicate that the TiO2 nanotube diameter and wall thickness are 100 nm to 120 nm and 20 nm to 30 nm, respectively. Moreover, the morphology and structure of the highly ordered TiO2 NTs are not affected by N-doping. Furthermore, CdS nanoparticles are evenly distributed on the surface of TiO2 NTs. Finally, the photocatalytic activity of CdS/N-TiO2 NTs was evaluated by degradation of MO under visible-light irradiation. Compared with TiO2 NTs, N-TiO2 NTs, CdS/N-TiO2 NTs exhibited enhanced photocatalytic properties, and the highest degradation rate of CdS/N-TiO2NTs could reach 97.6 % after 90 min of irradiation.

scholarly journals Performance of Graphene–CdS Hybrid Nanocomposite Thin Film for Applications in Cu(In,Ga)Se2 Solar Cell and H2 Production

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 245 ◽  
Author(s):  
Alhammadi ◽  
Minnam Reddy ◽  
Gedi ◽  
Park ◽  
Sayed ◽  
...  
Keyword(s):  
Thin Film ◽  
Buffer Layer ◽  
Photoelectron Spectroscopy ◽  
Atomic Ratio ◽  
H2 Production ◽  
Binding Energies ◽  
Cds Nanoparticles ◽  
X Ray ◽  
Chemical Solution Method ◽  
Transmission Electron

A graphene–cadmium sulfide (Gr–CdS) nanocomposite was prepared by a chemical solution method, and its material properties were characterized by several analysis techniques. The synthesized pure CdS nanoparticles (NPs) and Gr–CdS nanocomposites were confirmed to have a stoichiometric atomic ratio (Cd/S = 1:1). The Cd 3d and S 2p peaks of the Gr–CdS nanocomposite appeared at lower binding energies compared to those of the pure CdS NPs according to X-ray photoelectron spectroscopy analyses. The formation of the Gr–CdS nanocomposite was also evidenced by the structural analysis using Raman spectroscopy and X-ray diffraction. Transmission electron microscopy confirmed that CdS NPs were uniformly distributed on the graphene sheets. The absorption spectra of both the Gr–CdS nanocomposite and pure CdS NPs thin films showed an absorption edge at 550 nm related to the energy band gap of CdS (~2.42 eV). The Cu(In,Ga)Se2 thin film photovoltaic device with Gr–CdS nanocomposite buffer layer showed a higher electrical conversion efficiency than that with pure CdS NPs thin film buffer layer. In addition, the water splitting efficiency of the Gr–CdS nanocomposite was almost three times higher than that of pure CdS NPs.

scholarly journals Synthesis, Structural and Optical Properties of TOPO and HDA Capped Cadmium Sulphide Nanocrystals, and the Effect of Capping Ligand Concentration

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Damian C. Onwudiwe ◽  
Madalina Hrubaru ◽  
Eno E. Ebenso
Keyword(s):  
Optical Properties ◽  
Concentration Ratio ◽  
Cadmium Sulphide ◽  
Cds Nanoparticles ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
One Pot ◽  
X Ray ◽  
Quantum Size ◽  
Transmission Electron

The thermal decomposition of bis(N,N-diallyldithiocarbamato)Cd(II) in a “one-pot” synthesis in tri-n-octylphosphine oxide (TOPO) and hexadecylamine (HDA) afforded CdS (TOPO-CdS and HDA-CdS) of varying optical properties and morphologies. The influence of the ratio of the precursor concentration to the capping molecule, as a factor affecting the morphology and size of the nanoparticles, was investigated. The particles varied in shape from spheres to rods and show quantum size effects in their optical spectra with clear differences in the photoluminescence (PL) spectra. The PL spectrum of the HDA capped CdS nanoparticles has an emission maximum centred at 468, 472, and 484 nm for the precursor to HDA concentration ratio of 1 : 10, 1 : 15, and 1 : 20, respectively, while the TOPO capped nanoparticles show emission peaks at 483, 494, and 498 nm at the same concentration ratio. Powdered X-ray diffraction (p-XRD) shows the nanoparticles to be hexagonal. The crystallinity of the nanoparticles was evident from high resolution transmission electron microscopy (HRTEM) which gave well-defined images of particles with clear lattice fringes.

CHARACTERISTICS OF CdS NANOPARTICLES SYNTHESIZED BY SOLVOTHERMAL ROUTE WITH DIFFERENT RATIOS OF ETHYLENEDIAMINE/WATER

2005 ◽  
Vol 04 (04) ◽  
pp. 659-665
Author(s):  
JIANXI YAO ◽  
LI HONG ◽  
GAOLING ZHAO ◽  
WENJIAN WENG ◽  
GAORONG HAN
Keyword(s):  
Electron Microscopy ◽  
Cds Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvothermal Route ◽  
Cds Nanorods ◽  
Transmission Electron ◽  
Coordination Ability ◽  
The Difference ◽  
Xrd Patterns

CdS nanoparticles with various size and shape were synthesized through solvothermal route using different ratios of ethylenediamine/water. X-ray diffraction and transmission electron microscopy results revealed that CdS nanorods were formed by using ethylenediamine and the mixture of ethylenediamine and water as solvents. The CdS nanorods had [002] preferential orientation. When water was used as the solvent, irregular shape particles and typical XRD patterns of hexagonal CdS were observed. The produced nanoparticles displayed interesting photoluminescence feature, which were found to be sensitive to the ratio of ethylenediamine/water. It is suggested that the different coordination ability with Cd 2+ and dielectric constant of ethylenediamine and water caused different formation mechanism of CdS and led to the difference in the shape, crystallinity and optical properties of produced CdS particles.

scholarly journals Synthesis and characterization of CdS nanorods by combined sonochemical-solvothermal method

2016 ◽  
Vol 34 (3) ◽  
pp. 684-690 ◽  
Author(s):  
Pinar Acar Bozkurt ◽  
Burak Derkuş
Keyword(s):  
Solvothermal Method ◽  
Synthesis Method ◽  
Cds Nanoparticles ◽  
Synthesis Methods ◽  
Sonochemical Method ◽  
Factors Affecting ◽  
X Ray ◽  
Cds Nanorods ◽  
Transmission Electron ◽  
Comparison Of The Results

AbstractCadmium sulfide (CdS) nanorods with a diameter of 50 nm and length of approximately 200 nm have been synthesized using combined sonochemical-solvothermal method. Structural properties of CdS nanoparticles synthesized by this method have been compared with the CdS nanoparticles synthesized by sonochemical method alone. The synthesized CdS nanostructures have been characterized using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM) methods. In addition, the factors affecting the formation of the structures, including reaction time, different type and ratio of precursors, such as sulphur source, have been investigated. Comparison of the results obtained by both the synthesis methods revealed CdS nanoparticles synthesized by the combined sonochemical-solvothermal method to be of high morphological homogeneity compared to the sonochemical method alone. It is interesting to note that ethylenediamine has been found to be prevented from agglomeration by using the combined sonochemical-solvothermal method as the synthesis method. A modified growth mechanism under the inducement of ethylenediamine solutions for the CdS nanorods has been suggested.

Observation of Dominant Nuclei and Magic-Sized CdS Nanoparticles in a Single-Phase System

2021 ◽  
Vol 21 (12) ◽  
pp. 5987-5992
Author(s):  
Xiaobo Nie ◽  
Yanming Chen
Keyword(s):  
Single Phase ◽  
Cadmium Acetate ◽  
Nucleation And Growth ◽  
Precursor Concentration ◽  
Cds Nanoparticles ◽  
Phase System ◽  
Dilute Solution ◽  
Exciton Absorption ◽  
X Ray ◽  
Transmission Electron

Cadmium sulfide nanoparticles (CdS NPs) were synthesized by using cadmium acetate and thiourea as precursors and sodium oleate as the surfactant under different cadmium acetate concentrations in anhydrous ethanol. Cadmium (Cd) precursor concentration greatly affected the nucleation-growth of CdS NPs. In extremely dilute solution with a Cd precursor concentration of 0.1 mmol · L−1, an overlapped nucleation and growth corresponding to two pronounced absorption peaks at 310 nm and 350 nm, respectively, was observed. Unparalleled nucleation was dominant within very long reaction time until 10 hours. The nuclei and the resulting magic-sized CdS NPs may be used as seeds to prepare size and shape controllable nanoparticles. On the contrary, at a high Cd precursor concentration (5 mmol · L−1), nucleation and growth were separated. Only one first exciton absorption peak standing for the growth of regular CdS NPs appeared at 440 nm. Many techniques including transmission electron microscopy (TEM), X-ray powder diffraction (XRD), ultraviolet-visible (UV-Vis) absorption and photoluminescence (PL) spectrometers were applied to characterize the morphology, crystalline structure, and optical properties of CdS NPs.

The Fate of Polyol-Made ZnO and CdS Nanoparticles in Seine River Water (Paris, France)

2015 ◽  
Vol 15 (5) ◽  
pp. 3900-3908 ◽  
Author(s):  
Alice Da Rocha ◽  
Yann Sivry ◽  
Alexandre Gelabert ◽  
Zyed Beji ◽  
Marc F. Benedetti ◽  
...  
Keyword(s):  
River Water ◽  
Cds Nanoparticles ◽  
Seine River

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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