scholarly journals In-situ Observation of Fullerene Ultrathin Films by Using Total Reflection X-ray Diffraction-Organic Molecular Beam Deposition Method(TRXD-OMBD).

Hyomen Kagaku ◽  
1997 ◽  
Vol 18 (3) ◽  
pp. 178-184
Author(s):  
Yuji YOSHIDA ◽  
Nobutaka TANIGAKI ◽  
Kiyoshi YASE
Keyword(s):  
Ultrathin Films ◽  
Molecular Beam ◽  
Total Reflection ◽  
In Situ Observation ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molecular Beam Deposition ◽  
Beam Deposition

Interfacial Superstructures Studied by Grazing Incidence X-Ray Diffraction

1989 ◽  
Vol 159 ◽  
Author(s):  
Koichi Akimoto ◽  
Jun'Ichiro Mizuki ◽  
Ichiro Hirosawa ◽  
Junji Matsui
Keyword(s):  
Synchrotron Radiation ◽  
Direct Observation ◽  
Molecular Beam ◽  
Solid Phase ◽  
Grazing Incidence ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molecular Beam Deposition ◽  
Beam Deposition

ABSTRACTSurface superstructures (reconstructed structures) have been observed by many authors. However, it is not easy to confirm that a superstructure does exist at an interface between two solid layers. The present paper reports a direct observation, by a grazing incidence x-ray diffraction technique with use of synchrotron radiation, of superstructures at the interface. Firstly, the boron-induced R30° reconstruction at the Si interface has been investigated. At the a Si/Si(111) interface, boron atoms at 1/3 ML are substituted for silicon atoms, thus forming a R30° lattice. Even at the interface between a solid phase epitaxial Si(111) layer and a Si(111) substrate, the boron-induced R30° reconstruction has been also observed. Secondly, SiO2/Si(100)-2×l interfacial superstructures have been investigated. Interfacial superstructures have been only observed in the samples of which SiO2 layers have been deposited with a molecular beam deposition method. Finally, the interfaces of MOCVD-grown AIN/GaAs(100) have been shown to have 1×4 and 1×6 superstructures.

In situ X-ray characterization of oligophenylene thin films prepared by organic molecular beam deposition

1998 ◽  
Vol 130-132 ◽  
pp. 651-657 ◽  
Author(s):  
Yuji Yoshida ◽  
Hiroshi Takiguchi ◽  
Takeshi Hanada ◽  
Nobutaka Tanigaki ◽  
Eun Mi Han ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Beam ◽  
X Ray ◽  
Molecular Beam Deposition ◽  
Beam Deposition

Molecular multilayers: structure and templating effects

2000 ◽  
Vol 620 ◽  
Author(s):  
Sandrine Heutz ◽  
Sallie M. Bayliss ◽  
Rudi Cloots ◽  
Ruth L. Middleton ◽  
Garry Rumbles ◽  
...  
Keyword(s):  
Molecular Beam ◽  
Double Layers ◽  
X Ray Diffraction ◽  
Multilayered Structures ◽  
X Ray ◽  
Metal Free ◽  
Molecular Beam Deposition ◽  
Polymorphic Forms ◽  
Templating Effect ◽  
Beam Deposition

ABSTRACTPowder X-Ray diffraction (XRD) has been used to study multilayered structures grown by, organic molecular beam deposition based on the molecular materials PTCDA and metal-free phthalocyanine (H2Pc). Double layers of different polymorphic forms (α, β1 and β2) of H2Pc indicate that the structure of the second layer is determined by the properties of the first layer. It is also shown that the first layer completely disrupts the crystallinity of the second layer in heterostructures containing PTCDA and H2Pc. The implication is that a strong templating effect occurs during the growth of multilayer molecular thin film structures.

A Study on the Growth of Cubic GaN Films Using an AlGaAs Buffer Layer Grown on GaAs (100) by Plasma-Assisted Molecular Beam Epitaxy

2000 ◽  
Vol 639 ◽  
Author(s):  
Ryuhei Kimura ◽  
Kiyoshi Takahashi ◽  
H. T. Grahn
Keyword(s):  
Molecular Beam Epitaxy ◽  
Buffer Layer ◽  
Molecular Beam ◽  
High Energy ◽  
Rf Plasma ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cubic Gan

ABSTRACTAn investigation of the growth mechanism for RF-plasma assisted molecular beam epitaxy of cubic GaN films using a nitrided AlGaAs buffer layer was carried out by in-situ reflection high energy electron diffraction (RHEED) and high resolution X-ray diffraction (HRXRD). It was found that hexagonal GaN nuclei grow on (1, 1, 1) facets during nitridation of the AlGaAs buffer layer, but a highly pure, cubic-phase GaN epilayer was grown on the nitrided AlGaAs buffer layer.

scholarly journals In situ observation of phase changes of a silica-supported cobalt catalyst for the Fischer–Tropsch process by the development of a synchrotron-compatible in situ/operando powder X-ray diffraction cell

2018 ◽  
Vol 25 (6) ◽  
pp. 1673-1682 ◽  
Author(s):  
Adam S. Hoffman ◽  
Joseph A. Singh ◽  
Stacey F. Bent ◽  
Simon R. Bare
Keyword(s):  
High Pressure ◽  
Elevated Pressure ◽  
Phase Changes ◽  
In Situ Observation ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
X Ray ◽  
And Performance ◽  
Co Nanoparticles

In situ characterization of catalysts gives direct insight into the working state of the material. Here, the design and performance characteristics of a universal in situ synchrotron-compatible X-ray diffraction cell capable of operation at high temperature and high pressure, 1373 K, and 35 bar, respectively, are reported. Its performance is demonstrated by characterizing a cobalt-based catalyst used in a prototypical high-pressure catalytic reaction, the Fischer–Tropsch synthesis, using X-ray diffraction. Cobalt nanoparticles supported on silica were studied in situ during Fischer–Tropsch catalysis using syngas, H2 and CO, at 723 K and 20 bar. Post reaction, the Co nanoparticles were carburized at elevated pressure, demonstrating an increased rate of carburization compared with atmospheric studies.

Sign in / Sign up

Export Citation Format

Share Document