Physical and optical properties of small metal particle composites

1978 ◽  
Author(s):  
H. G. Craighead ◽  
R. A. Buhrman
1992 ◽  
Vol 286 ◽  
Author(s):  
Colby A. Foss ◽  
Gabor L. Hornyak ◽  
Jon A. Stockert ◽  
Charles R. Martin

ABSTRACTAn electrochemical method for the preparation of nanoscopic gold particles which allows for the control of particle size, shape and orientation is described. The UV/visible/near-IR spectra of Au/alumina and Au/polyethylene composites are described and shown to be in accord with the predictions of Maxwell-Garnett theory. The applications of such composites to surface enhanced spectroscopy are also discussed.


Author(s):  
M. Jose Yacaman

In the Study of small metal particles the shape is a very Important parameter. Using electron microscopy Ino and Owaga(l) have studied the shape of twinned particles of gold. In that work electron diffraction and contrast (dark field) experiments were used to produce models of a crystal particle. In this work we report a method which can give direct information about the shape of an small metal particle in the amstrong- size range with high resolution. The diffraction pattern of a sample containing small metal particles contains in general several systematic and non- systematic reflections and a two-beam condition can not be used in practice. However a N-beam condition produces a reduced extinction distance. On the other hand if a beam is out of the bragg condition the effective extinction distance is even more reduced.


1999 ◽  
Vol 60 (20) ◽  
pp. R13977-R13980 ◽  
Author(s):  
P. W. Brouwer ◽  
Yuval Oreg ◽  
B. I. Halperin

1985 ◽  
Vol 18 (26) ◽  
pp. L837-L842 ◽  
Author(s):  
W J Kaiser ◽  
E M Logothetis ◽  
L E Wenger

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 485
Author(s):  
Ming Zhang ◽  
Zhen Song ◽  
Mengquan Guo ◽  
Xiangxiang Li ◽  
Yanjun Lin ◽  
...  

The effect of reduction atmospheres, H2/N2, C3H8/H2/N2, C3H8 and CO, on the structure and propane direct dehydrogenation performance of PtIn/Mg(Al)O/ZnO catalyst derived from ZnO-supported PtIn-hydrotalcite was studied. The physicochemical properties of the as-prepared and used catalytic system were characterized by various characterization methods. The results show that the dehydrogenation performance, especially the stability of the PtIn/Mg(Al)O/ZnO catalyst, was significantly improved along with the change in reduction atmosphere. The highest catalytic activity (51% of propane conversion and 97% propylene selectivity), resistance toward coke deposition, and stability for more than 30 h were achieved with the H2/N2-reduced catalyst. The optimal dehydrogenation performance and coke resistance are mainly related to the high Pt dispersion and In0/In3+ molar ratio, strong Pt–In interaction and small metal particle size, depending on the nature of the reduction atmospheres. The reconstruction of meixnerite favors the stability and coke resistance to some extent.


Sign in / Sign up

Export Citation Format

Share Document