Platinum particles support

Honji A, Mori T, Tamura K, Hishinuma Y. 1988. Agglomeration of platinum particles supported on carbon in phosphoric acid. J Electrochem Soc 135 355-359. 

Masson, A., Bellamy, B., Romdhane, Y. H., Che, M., Roulet, H., and Dufour, G., Intrinsic size effect of platinum particles supported on plasma-grown amorphous alumina in the hydrogenation of ethylene. Surf. Sci. 173, 479 (1986). 

In subsequent experiments (58b) carried out with a more sensitive spectrometer (MAPS at ISIS) it was possible to detect the Pt-H stretch of the on-top site on Pt(40%)/C at 2079 cm. This is a significant result, representing the first time that hydrogen on the on-top sites has been observed on nanosized platinum particles supported on high surface area carbon black. The INS peak is surprisingly wide and may give additional information about the type and relative proportions of the crystallographic faces present on the catalyst particles. 

The discussion to this point has emphasized kinetics of catalytic reactions on a uniform surface where only one type of active site participates in the reaction. Bifunctional catalysts operate by utilizing two different types of catalytic sites on the same solid. For example, hydrocarbon reforming reactions that are used to upgrade motor fuels are catalyzed by platinum particles supported on acidified alumina. Extensive research revealed that the metallic function of Pt/Al203 catalyzes hydrogenation/dehydrogenation of hydrocarbons, whereas the acidic function of the support facilitates skeletal isomerization of alkenes. The isomerization of n-pentane (N) to isopentane (I) is used to illustrate the kinetic sequence associated with a bifunctional Pt/Al203 catalyst ... 

Figure 4.22. Simulated images obtained using a model of a platinum particle supported on a (111) surface of CeOi in a parallel orientation relationship both in profile view a) and planar view b). The same particle rotated 2" from the perfect alignment between both stnictures c) and d). The DDPs obtained from the planar view simulated images are also shown (387).

General interaction pathway example of the reaction of tetraalkyltin complexes on platinum particles supported onto silica... 

While there are exceptions, most fuel cell developers have gravitated toward a common means of making a catalyst layer. Generally speaking, most catalyst layers employ a structure of platinum particles supported on carbon. The primary carbon particles are approximately 40 nm in diameter... 

We have observed that carbon-supported nanoscale platinum electrodes retain quite closely the Pt NMR spectral characteristics of isolated small platinum particles supported on oxides [4, 7, 25, 30], with the clean-surface platinum atoms also resonating at 1.100 G kHz with respect to the value for bulk atoms, 1.138 G kHz . We show in Fig. 4(a-c), Pt NMR spectra... 

Fig. 4. High resolution electron micrograph of platinum particles supported on graphi-tized carbon. Courtesy of B. Tesche, Max-Planck-Institut fur Kohleforschung, Miilheim, Germany.

Maoka, T. (1988) Electrochemical reduction of oxygen on small platinum particles supported on carbon in concentrated phosphoric acid - 1. ElFects of platinum content in the catalyst... 

Ottalram Thotiyl, MA4., Ravikumar, T., and Sampath, S. (2010) Platinum particles supported on titanium nitride an efficient electrode material for the oxidation of methanol in alkaline media. Journal... 

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