The importance of superficial (adatom) surface oxidation in the electrocatalytic behaviour of noble metals in aqueous media

1989 ◽  
Vol 19 (5) ◽  
pp. 758-767 ◽  
Author(s):  
L. D. Burke ◽  
W. A. O'Leary
2020 ◽  
Vol 2020 ◽  
pp. 1-24 ◽  
Author(s):  
Carmen Cretu ◽  
Loredana Maiuolo ◽  
Domenico Lombardo ◽  
Elisabeta I. Szerb ◽  
Pietro Calandra

The involvement of metal ions within the self-assembly spontaneously occurring in surfactant-based systems gives additional and interesting features. The electronic states of the metal, together with the bonds that can be established with the organic amphiphilic counterpart, are the factors triggering new photophysical properties. Moreover, the availability of stimuli-responsive supramolecular amphiphile assemblies, able to disassemble in a back-process, provides reversible switching particularly useful in novel approaches and applications giving rise to truly smart materials. In particular, small amphiphiles with an inner distribution, within their molecular architecture, of various polar and apolar functional groups, can give a wide variety of interactions and therefore enriched self-assemblies. If it is joined with the opportune presence and localization of noble metals, whose chemical and photophysical properties are undiscussed, then very interesting materials can be obtained. In this minireview, the basic concepts on self-assembly of small amphiphilic molecules with noble metals are shown with particular reference to the photophysical properties aiming at furnishing to the reader a panoramic view of these exciting problematics. In this respect, the following will be shown: (i) the principles of self-assembly of amphiphiles that involve noble metals, (ii) examples of amphiphiles and amphiphile-noble metal systems as representatives of systems with enhanced photophysical properties, and (iii) final comments and perspectives with some examples of modern applications.


2000 ◽  
Vol 45 (25-26) ◽  
pp. 4127-4134 ◽  
Author(s):  
L.D Burke ◽  
J.A Collins ◽  
M.A Horgan ◽  
L.M Hurley ◽  
A.P O'Mullane

2012 ◽  
Vol 3 (3-4) ◽  
pp. 170-175 ◽  
Author(s):  
Khaled A. Soliman ◽  
Ludwig A. Kibler ◽  
Dieter M. Kolb

2006 ◽  
Vol 51 (27) ◽  
pp. 6159-6164 ◽  
Author(s):  
K. Juodkazis ◽  
J. Juodkazytė ◽  
T. Juodienė ◽  
V. Šukienė ◽  
I. Savickaja

2017 ◽  
Vol 35 (5) ◽  
pp. 05C304 ◽  
Author(s):  
Jack Kun-Chieh Chen ◽  
Nicholas D. Altieri ◽  
Taeseung Kim ◽  
Thorsten Lill ◽  
Meihua Shen ◽  
...  

Author(s):  
S. McKernan ◽  
C. B. Carter

The oxidation of natural olivine has previously been performed on bulk samples and the reactions followed by preparation of TEM specimens from the annealed material. These results show that below ∼1000°C hematite and amorphous silica are formed, particularly around dislocations. At higher temperatures magnetite and some enstatite-like phase are formed. In both cases the olivine is left almost totally Fe depleted. By performing the oxidation on characterized thin TEM specimens it is possible to obtain more information on the nucleation and growth of the second phases formed. The conditions in a thin foil, however, are very different from those in the bulk especially with regard to surface effects. The nucleation of precipitates in particular may be expected to occur differently in these thin foils than in the bulk.TEM specimens of natural olivine (approximate composition Mg+Fe+Si2o4) which had been annealed at 1000°C for 1 hr were prepared by mechanical polishing and dimpling, followed by Ar ion milling to perforation. The specimens were characterized in the electron microscope and then heated in air in alumina boats to 900°C for between 30 and 180 minutes.


Author(s):  
E. I. Alessandrini ◽  
M. O. Aboelfotoh

Considerable interest has been generated in solid state reactions between thin films of near noble metals and silicon. These metals deposited on Si form numerous stable chemical compounds at low temperatures and have found applications as Schottky barrier contacts to silicon in VLSI devices. Since the very first phase that nucleates in contact with Si determines the barrier properties, the purpose of our study was to investigate the silicide formation of the near noble metals, Pd and Pt, at very thin thickness of the metal films on amorphous silicon.Films of Pd and Pt in the thickness range of 0.5nm to 20nm were made by room temperature evaporation on 40nm thick amorphous Si films, which were first deposited on 30nm thick amorphous Si3N4 membranes in a window configuration. The deposition rate was 0.1 to 0.5nm/sec and the pressure during deposition was 3 x 10 -7 Torr. The samples were annealed at temperatures in the range from 200° to 650°C in a furnace with helium purified by hot (950°C) Ti particles. Transmission electron microscopy and diffraction techniques were used to evaluate changes in structure and morphology of the phases formed as a function of metal thickness and annealing temperature.


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