Pt substrates

Figure 2 Schematic views of the layer sequence of the ordered structures discussed in the text the CusPt single crystal (left panel), the ordered overlayer of CusPt on the Pt substrate (middle panel) and the ordered overlayer of CusPts on Pt (right panel).

Fig. 13. Cyclic voltammograin for the charging/discharging of polyaniline on Pt substrate at different scan rates, ref. 214 (reprinted by permission of the publisher, The Electrochemical Society, Inc.)...

The ECALE synthesis of V-VI (V Sb, Bi) compounds has been attempted in a few works. Antimony telluride, Sb2Te3, nanofilms with a homogeneous microstructure and an average size of about 20 nm were formed epitaxially on a Pt substrate [61]. The optical band gap of these films was blue-shifted in comparison with that of the bulk single-crystal Sb2Tc3 compound. 

The Enzymes II (E-IIs) of the phosphoenolpyruvate (P-enolpyruvate)-dependent phosphotransferase system (PTS) are carbohydrate transporters found only in prokaryotes. They not only transport hexoses and hexitols, but also pentitols and disaccharides. The PTS substrates are listed in Table I. The abbreviations used (as superscripts) throughout the text for these substrates are as follows Bgl, jS-gluco-side Cel, cellobiose Fru, fructose Glc, glucose Gut, glucitol Lac, lactose Man, mannose Mtl, mannitol Nag, iV-acetylglucosamine Scr, sucrose Sor, sorbose Xtl, xylitol. 

The physical origin of this structural flexibility of the FeO overlayer is still unclear, the more so since no clear trend is observable in the sequence of lattice parameters of the coincidence structures. The FeO(l 11) phase forming up to coverages of 2-3 ML is clearly stabilized by the interactions with the Pt substrate since FeO is thermodynamically metastable with respect to the higher iron oxides [106,114], FeO has the rock salt structure and the (111) plane yields a polar surface with a high surface energy [115], which requires stabilization by internal reconstruction or external compensation. The structural relaxation observed in the form of the reduced Fe—O... 

These results suggest that the critical factor in the substrate-mediated intermolecular interactions which occur within the close-packed DHT layer is the inherent strong reactivity of the diphenolic moiety with the Pt surface. The interaction of adsorbates with each other through the mediation of the substrate is of fundamental importance in surface science. The theoretical treatment, however, involves complicated many-body potentials which are presently not well-understood (2.). It is instructive to view the present case of Pt-substrate-mediated DHT-DHT interactions in terms of mixed-valence metal complexes (2A) For example, in the binuclear mixed-valence complex, (NH3)5RU(11)-bpy-Ru(111) (NH 3)5 (where bpy is 4,4 -bipyridine), the two metal centers are still able to interact with each other via the delocalized electrons within the bpy ligand. The interaction between the Ru(II) and Ru(III) ions in this mixed-valence complex is therefore ligand-mediated. The Ru(II)-Ru(III) coupling can be written schematically as ... 

The NO LID results on Pt(lll), Pd(lll) and Pt(foil) are strongly marked both by their dramatic similarities and their subtle differences. All exhibit a thermal LID component with high degrees of translational and rotational accommodation. For the Pt substrates the non-Boltzmann component exhibits (1) anomolously high, state-dependent kinetic energies (2) spin-orbit... 

LiMii204) electrochemical kinetics ensure that all of the surfaces of the nanotubules remain accessible to solvent and electrolyte. The polypyrrole coat was deposited by simply applying 5 al of a solution that was 1 M in HCIO4 and 0.2 M in pyrrole to the LiMn204 surface. This results in oxidative polymerization of all of the pyrrole, yielding 0.065 mg of polypyrrole per cm of Pt substrate surface [125]. 

For example, the voltammogram in Fig. 1 depicts Ag UPD on an I-coated Pt(lll) electrode [26], Three features can be attributed to the UPD of Ag, each of which results in the formation of a new structure on the surface, as indicated by the FEED patterns diagrammed in the circles. It was concluded in that work that UPD involved more than a single monolayer of Ag. Ag depositing at underpotential reacted with the Pt substrate as well as with the adsorbed I atom layer. It is also interesting to note that Ag underpotentially deposited in Fig. 1 reacted with the adsorbed atomic layer of I atoms to form a monolayer of the I-VII compound Agl on the Pt surface. 

Fig. 9.12 Cyclic voltammetry of the p-doping(anodic)-undoping(cathodic) process of a polypyrrole electrode in LiClO -PC solution. Pt substrate, Li reference electrode, scan rate 50 mV s .

On Pt, the mode of isocyanide adsorption depends on the nature of the Pt substrate and perhaps on the nature of the isocyanide. On Pt(lll), CH3NC adsorbs by both T (low coverage) and p,2-T h (high coverage) modes. On Pt nanoparticles, only T adsorption is observed for n-dodecyl isocyanide, but on Pt nanoparticle electrodes evidence suggests that DMPI adsorbs by T (on-top), X2-T t (two-fold bridge) and X2-tl T T (three-fold hollow) modes. 

Computational studies indicated that Pt monolayers on non-Pt substrates exhibit distinct oxygen adsorption and reduction characteristics. In particular, the Pt—OH and Pt— binding energies were predicted to decrease compared to a pure Pt surface. In the light of the previous discussion in Section 4.1.4 of the origin of the overpotential in the ORR reaction, the Pt— reduction process becomes activated at a higher electrode potential compared to pure Pt. 

There were no substantial differences between the magnitudes of the photovoltages on the different substrate electrodes despite the 1,4-V range in their vacuum work functions (Fig. 7). The slight decrease in Voc on Pt substrates was caused by the enhanced rate of recombination at this highly catalytic electrode... 

A safe synthesis of a number of metal fulminato-complexes, including [Pt(R3E)2-(CNO)J (E = P, As or Sb) and [PtX(CNO)(PPh3)2], (X = H, H, Me, CN or NCO) by reaction of AsPh4CNO with the appropriate Pt substrate has been reported." The thermally very stable complex [Pt(CNO)2(PPh3)2] was shown to isomerize to the isocyahato-complex under mild conditions, and to be reduced by phosphines to the cyanide [Pt(CN)2(PPh3)2].99 Other fulminato-complexes have been synthesized (equation 39) (R = Ph, Me or Et), and again i.r. evidence also shows isomerization... 

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