Pt-nanoclusters

FIGURE 27.18 (A) Weakly ordered Pt nanoclusters deposited spontaneously on a Ru(OOOl)... 

Different from the metal concentration, the content of water in the reaction system exhibits an obvious effect on the particle size of the resulted metal nanoclusters. In a mixture of EG and water (10 1 in volume ratio), Pt hydroxide colloidal particles formed in the first synthesis step were 4.0 nm in average diameter, and the finally obtained Pt nanoclusters had an average particle size of... 

Figure 1. TEM images and size distributions of Pt, Rh and Ru nanoclusters stabilized by EG and simple ions [11] (a) Pt nanoclusters (0.37g/1) (b) Pt nanoclusters (3.7g/1) (c) Rh nanoclusters (0.31 g/1) (d) Ru nanoclusters (0.32g/1). (Reprinted from Ref [11], 2000, with permission from American Chemical Society.)...

Table 3. XPS data for the ligand-modified Pt nanoclusters and ligands.

Selective Deposition of Pt Nanoclusters on Well-Defined Materials... 

The dispersion of Pt(0) inside the functionalized resins was carried out by two main routes. The first is based on impregnation of the resin with a mesitylene solution of Pt nanoclusters (Solvated Pt Atoms) obtained via MVS. The second procedure, called Chemical Incorporation and Reduction (CIR), implies the immobilization of convenient molecular Pt precursors (i.e. [Pt(NH3)4]Cl2) in the pre-swollen resins, followed by chemical reduction of the metal center. Among the Pt catalysts obtained by the CIR procedure only Pt/CF3 exhibits a high conversion of the... 

Fig. 15. Schematic illustration of the method used to prepare dendrimer-encapsulated Ag,Au, Pd, and Pt nanoclusters by primary and secondary displacement reactions using G6-OH(Cu ) or G6-OH(Ag2n) as starting materials...

Dendrimer-Encapsulated Pt Nanoclusters as Heterogeneous Electrocatalysts for O2 Reduction... 

Pt NANOCLUSTERS ON CARBON NANOMATERIALS FOR HYDROGEN FUEL CELLS... 

Keywords Single-walled nanotubes Multi-walled nanotubes Nanofibers Amorphous carbon Pt nanoclusters Fuel cell. 

In recent years, we have been investigating easy and economical functionalization of widely nsed carbon based polymers snch as polybntadienes. The preliminary results of these studies have led our group to discover a highly selective and mild synthetic route to silyl-functionalization of 1,2-polybutadienes (PBD) via Pt-nanocluster catalyzed hydrosilylation of olefin bonds. Unlike other catalytic systems, our system was found to be equally effective with all varieties of functional silanes such as halo-, alkyl-, aryl- and alkoxy- silanes affording high yields and selectivities. In addition, all the hydrosilylation reactions were found to be very clean with the ease of product separation and purifications (Scheme 2). 

Conditions [PBD-1] = l.Ommol [silane] = 1.2 mmol Pt-nanocluster= (O.OlOgm) Solvent Benzene, Yields are based on isolated products. The isolation was performed under nitrogen atmosphere. 

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