Characterization of DLC films by EELS and electron holography

2005 ◽  
Vol 54 (1) ◽  
pp. 11-17 ◽  
Author(s):  
D. Shindo
Keyword(s):  
2000 ◽  
Vol 6 (S2) ◽  
pp. 228-229
Author(s):  
M. A. Schofield ◽  
Y. Zhu

Quantitative off-axis electron holography in a transmission electron microscope (TEM) requires careful design of experiment specific to instrumental characteristics. For example, the spatial resolution desired for a particular holography experiment imposes requirements on the spacing of the interference fringes to be recorded. This fringe spacing depends upon the geometric configuration of the TEM/electron biprism system, which is experimentally fixed, but also upon the voltage applied to the biprism wire of the holography unit, which is experimentally adjustable. Hence, knowledge of the holographic interference fringe spacing as a function of applied voltage to the electron biprism is essential to the design of a specific holography experiment. Furthermore, additional instrumental parameters, such as the coherence and virtual size of the electron source, for example, affect the quality of recorded holograms through their effect on the contrast of the holographic fringes.


2005 ◽  
Vol 900 ◽  
Author(s):  
Satoshi Ichikawa ◽  
Tomoki Akita ◽  
Kazuyuki Okazaki ◽  
Koji Tanaka ◽  
Masanori Kohyama

ABSTRACTCatalytic properties of noble metal catalysts are often caused by their nanostructures and the interaction between nano particles and oxides supports. We examine the mean inner potential of Pd particles in Pd/TiO2 catalyst and Ag particles in Ag/TiO2 catalysts using electron holography and HRTEM. And we compare the results of the Pd/TiO2 and Ag/TiO2 systems with our previous results of the Au/TiO2 and Pt/TiO2 systems. In the case of the Pd/TiO2 catalysts, when the size of Pd particle is smaller than 5nm, the mean inner potential of Pd changes to be higher than the calculated value of the mean inner potential which is thought to be higher than the experimental values of bulk Pd by 3-5V. The mean inner potential of Pd becomes to increase gradually as the size of the Pd particle decreases. The rate of the increment in the mean inner potential of Pd is lower than that of Au/TiO2 catalysts and Pt/TiO2 catalysts. On the other hand, in the case of Ag/TiO2 catalysts, the mean inner potential of Ag does not increase though the size of the Ag particle decreases to under 2nm.


2017 ◽  
Vol 23 (S1) ◽  
pp. 1404-1405
Author(s):  
Lin Zhou ◽  
Zhaofeng Gan ◽  
Myung-Geun Han ◽  
David J. Smith ◽  
Martha R. McCartney

2005 ◽  
Vol 87 (22) ◽  
pp. 223109 ◽  
Author(s):  
R. C. Che ◽  
M. Takeguchi ◽  
M. Shimojo ◽  
W. Zhang ◽  
K. Furuya

2005 ◽  
Vol 631 (6-7) ◽  
pp. 983-992 ◽  
Author(s):  
Paul Simon ◽  
Hannes Lichte ◽  
Damian M�nter ◽  
Wladimir Reschetilowski ◽  
Anibal Valera ◽  
...  

2004 ◽  
Vol 839 ◽  
Author(s):  
S. Ichikawa ◽  
T. Akita ◽  
K. Okazaki ◽  
K. Tanaka ◽  
M. Kohyama

ABSTRACTWe investigated the atomic structure near the interface and the size dependence of the mean inner potential of gold in Au/TiO2 catalysts prepared by the deposition precipitation (DP) method and the vacuum evaporation (VE) method using high resolution electron microscopy (HREM) and electron holography. The TiO2 supports prepared by DP method and VE method are considered to have oxygen-rich surfaces and titanium-rich surfaces respectively. In case of the Au/TiO2 catalyst prepared by DP method, the mean inner potential of gold increased depending on the size of the particle. When the size of the gold particle is over 5nm, the mean inner potential of gold was the same as that of bulk Au. When the size is below 5nm, the mean inner potential became to increase. It increases suddenly over 40V, particularly in case of below 2nm. It indicates that the electronic state of gold on TiO2 changes from that of bulk state as the size decreases. On the other hand, the mean inner potential of gold in Au/TiO2 catalysts prepared by VE method also increased as the size decreased, but the behavior of the size dependence is different from that of DP method. The critical size of the mean inner potential change is around 3nm. The size of the gold particle was below 3nm, the mean inner potential of gold increased gradually. The mean inner potential of VE method is less than that of DP method with the same particle size in spite of the size below 3nm. The stoichiometry at the interface between Au and TiO2 should be one of the dominant reasons for the behavior difference of the size dependence of the mean inner potential between the preparations.


2006 ◽  
Vol 100 (2) ◽  
pp. 023519 ◽  
Author(s):  
E. Snoeck ◽  
J. Majimel ◽  
M. O. Ruault ◽  
M. J. Hÿtch

2007 ◽  
Author(s):  
Nobuyuki Ikarashi ◽  
Makiko Oshida ◽  
Makoto Miyamura ◽  
Motofumi Saitoh ◽  
Akira Mineji ◽  
...  

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