Determination of the Growth Rate of Hydrothermally Synthesised ZnO2 Crystallites

2017 ◽  
Vol 50 ◽  
pp. 41-47 ◽  
Author(s):  
Martin Egblewogbe ◽  
Garu Gebreyesus ◽  
Samuel A. Atarah
Keyword(s):  
Growth Rate ◽  
Zinc Acetate Dihydrate ◽  
Hydrothermal Process ◽  
Growth Rate Constant ◽  
Acetate Dihydrate ◽  
X Ray ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Zinc Peroxide

Powders consisting of nanoparticles of zinc peroxide were prepared via a simple hydrothermal process using zinc acetate dihydrate and hydrogen peroxide precursors. The size of the crystallites was determined using x-ray powder diffraction. Over a period of 5 hours the crystallite radius increased from 4 nm – 9 nm at a temperature of 68 °C ± 5 °C, with growth rate constant of 0.23 nm3 min−1 calculated using the Lifshitz, Slyozov, and Wagner model. The powders were further characterised with High Resolution Transmission Electron Microscopy, Energy Dispersive X-ray analysis, and Small Angle X-ray Scattering, showing well-crystallised ZnO2 nanoparticles.

Synthesis of ZnO2 Nanocrystals Produced by Hydrothermal Process

2009 ◽  
Vol 1242 ◽  
Author(s):  
R. Esparza ◽  
A. Aguilar ◽  
A. Escobedo-Morales ◽  
C. Patiño-Carachure ◽  
U. Pal ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Hydrogen Peroxide ◽  
Transmission Electron Microscopy ◽  
Hydrothermal Process ◽  
High Resolution Electron Microscopy ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Zinc Peroxide ◽  
20 Nm

ABSTRACTZinc peroxide (ZnO2) nanocrystals were directly produced by hydrothermal process. The nanocrystals were synthesized using zinc acetate as precursor and hydrogen peroxide as oxidant agent. The ZnO2 powders were characterized by X-ray powder diffraction and transmission electron microscopy. The results of transmission electron microscopy indicated that the ZnO2powders consisted of nanocrystals with diameters below to 20 nm and a faceted morphology. High resolution electron microscopy observations have been used in order to the structural characterization. ZnO2 nanocrystals exhibit a well-crystallized structure.

scholarly journals Alpha helical surfactant-like peptides self-assemble into pH-dependent nanostructures

Soft Matter ◽  
2021 ◽  
Vol 17 (11) ◽  
pp. 3096-3104
Author(s):  
Valeria Castelletto ◽  
Jani Seitsonen ◽  
Janne Ruokolainen ◽  
Ian W. Hamley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Small Angle ◽  
Self Assembly ◽  
X Ray ◽  
Cryogenic Transmission Electron Microscopy ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Ph Dependent ◽  
Ray Scattering

A designed surfactant-like peptide is shown, using a combination of cryogenic-transmission electron microscopy and small-angle X-ray scattering, to have remarkable pH-dependent self-assembly properties.

On the selective aerobic oxidation of benzyl alcohol with Pd/Au-nanoparticles in batch and flow

2014 ◽  
Vol 3 (1) ◽  
pp. 99-110 ◽  
Author(s):  
Hannes Alex ◽  
Norbert Steinfeldt ◽  
Klaus Jähnisch ◽  
Matthias Bauer ◽  
Sandra Hübner
Keyword(s):  
Catalytic Activity ◽  
Benzyl Alcohol ◽  
Aerobic Oxidation ◽  
X Ray ◽  
X Ray Scattering ◽  
Oxidation Of Benzyl Alcohol ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Selective Aerobic Oxidation

AbstractNanoparticles (NP) have specific catalytic properties, which are influenced by parameters like their size, shape, or composition. Bimetallic NPs, composed of two metal elements can show an improved catalytic activity compared to the monometallic NPs. We, herein, report on the selective aerobic oxidation of benzyl alcohol catalyzed by unsupported Pd/Au and Pd NPs at atmospheric pressure. NPs of varying compositions were synthesized and characterized by UV/Vis spectroscopy, transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). The NPs were tested in the model reaction regarding their catalytic activity, stability, and recyclability in batch and continuous procedure. Additionally, in situ extended X-ray absorption fine structure (EXAFS) measurements were performed in order to get insight in the process during NP catalysis.

An X-ray scattering study on inverted Ge–Si huts grown at low temperatures

2004 ◽  
Vol 19 (4) ◽  
pp. 347-351
Author(s):  
J. Xu ◽  
X. S. Wu ◽  
B. Qian ◽  
J. F. Feng ◽  
S. S. Jiang ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Lattice Strain ◽  
Lattice Mismatch ◽  
Grazing Incidence ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Large Lattice ◽  
Scattering Study

Ge–Si inverted huts, which formed at the Si∕Ge interface of Si∕Ge superlattice grown at low temperatures, have been measured by X-ray diffraction, grazing incidence X-ray specular and off-specular reflectivities, and transmission electron microscopy (TEM). The surface of the Si∕Ge superlattice is smooth, and there are no Ge–Si huts appearing on the surface. The roughness of the surfaces is less than 3 Å. Large lattice strain induced by lattice mismatch between Si and Ge is found to be relaxed because of the intermixing of Ge and Si at the Si∕Ge interface.

Analysis of InGaN/GaN single quantum wells by X-ray scattering and transmission electron microscopy

2003 ◽  
Vol 240 (2) ◽  
pp. 297-300 ◽  
Author(s):  
T. M. Smeeton ◽  
M. J. Kappers ◽  
J. S. Barnard ◽  
M. E. Vickers ◽  
C. J. Humphreys
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Quantum Wells ◽  
Single Quantum ◽  
X Ray ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Ray Scattering

X-Ray Scattering Studies of Interfacial Microstructures in Inx, Ga1−x As/GaAs Superlattices

1994 ◽  
Vol 375 ◽  
Author(s):  
Z. H. Ming ◽  
Y. L. Soo ◽  
S. Huang ◽  
Y. H. Kao ◽  
K. Stair ◽  
...  
Keyword(s):  
Quantum Wires ◽  
Large Angle ◽  
Sample Surface ◽  
Lateral Direction ◽  
Direction Parallel ◽  
X Ray ◽  
Periodic Arrays ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Ray Scattering

AbstractInterfacial microstructures in 100-period InxGa1−xAs(15Å)/GaAs(100Å) superlattices grown on GaAs (100) substrates by molecular beam epitaxy were studied by using large angle x-ray scattering techniques. Unusual satellite peaks in the lateral direction parallel to the sample surface were observed in a sample with x = 0.535 grown at 480°C, indicating an in-plane structural ordering. This result is confirmed by high resolution transmission electron microscopy observations that thickness modulation in the InxGa1−xAs layers gives rise to long-range lateral periodic arrays of cluster-like microstructures with spacing on the order of a few hundred Ångstroms. This thickness modulation is found to occur only in [110] direction, thus the material can be viewed as a somewhat disordered array of grown-in parallel quantum wires.

Preparation and Characterization of Hybrid Graphene-ZnS Nanoparticles

2010 ◽  
Vol 663-665 ◽  
pp. 894-897
Author(s):  
Hua Huang ◽  
Hai Hu Yu ◽  
Ling De Zhou ◽  
Er Dan Gu ◽  
De Sheng Jiang
Keyword(s):  
Coupling Effect ◽  
Zinc Acetate Dihydrate ◽  
Graphene Sheets ◽  
Acetate Dihydrate ◽  
Zns Nanoparticles ◽  
Transmission Electron ◽  
Infrared Spectrometer ◽  
One Step ◽  
Average Size

Hybrid Graphene-ZnS nanopaticles (G-ZnS NPs) were prepared by using a solvothermal method. A dispersion of graphite oxide (GO) and zinc acetate dihydrate (Zn(CH3COO)2.2H2O) in dimethl sulfoxide (DMSO) reacted at 180 °C for 12 h in a Telfon-lined stainless steel autoclave. In the reaction, DMSO serves as a sulphide source as well as a reducing agent, resulting formation of the hybrid G-ZnS NPs in one-step. Hybrid G-ZnS NPs were characterized by using a powder X-ray diffractometer, a Fourier-transform infrared spectrometer, a transmission electron microscope, a UV-vis spectrophotometer and a fluorescence spectrophotometer, respectively. In the FTIR spectra, the GO related stretching bands of C-O and carboxyl groups are not observed in the spectra of G-ZnS, suggesting that the GO sheets were reduced to graphene sheets. In the TEM images, it is observed that the ZnS nanoparticles with an average size of 23 nm are attached onto the graphene sheets. The UV-vis absorption spectrum of the G-ZnS NPs dispersed in ethanol has an absorption peak of G at 261 nm and a weak shoulder of ZnS NPs around 320 nm. The broadening and weakening of the peak of ZnS NPs at 320 nm arises from the interparticle coupling effect. Under excitation at 225 nm, a peak around 386 nm and other weaker bands appear in the fluorescence spectrum of the G-ZnS. The band at 386 nm is attributed to zinc vacancies.

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