Dendrimer encapsulated platinum nanoparticles

X.L., and Li, C.Z. (2007) Amperometric glutamate biosensor based on selfassembling glutamate dehydrogenase and dendrimer-encapsulated platinum nanoparticles onto carbon nanombes. Talanta, 73, 438 43. 

PAMAM Dendrimer-Platinum Conjugates and Applications 2.1 PAMAM Dendrimer-Encapsulated Platinum Nanoparticles... 

Albiter MA, Crooks RM, Zaera F (2010) Adsorption of carbon monoxide on dendrimer-encapsulated platinum nanoparticles liquid versus gas phase. J Phys Chem Lett 1 38... 

Zhao et al (70) developed a method for the synthesis of dendrimer-encapsulated metal nanoparticles based on sorbing metal ions into (modified) PAMAM dendrimers followed by a reduction. Dendrimers encapsulating copper, palladium, and platinum nanoparticles have been prepared. Hydroxyl-terminated PAMAM dendrimers were used to prepare encapsulated palladium (PAMAM generations 4, 6, and 8) and platinum (PAMAM generations 4 and 6) nanoparticles. The dendrimer-encapsulated palladium and platinum nanocomposites catalyzed the hydrogenation reaction of allyl alcohol and N-isopropyl acrylamide in water 71). 

Dendrimer-encapsulated nanoparticles have potential applications in the energy sector. For example, polyamidoamine (PAMAM) dendrimer-encapsulated platinum nanoparlicles (Pt-DENs) have been introduced as a promising cathode catalyst for air-cathode single-chamber microbial fuel cells (SCMFCs) [64], This novel catalyst led to higher power production with 129.1%, as compared to cathodes with electrodeposited Pt. 

Palladium and Platinum. PHIP has been used to study the hydrogenation of phenyl acetylene by colloidal palladium.In situ P NMR spectroscopy has been used to show the resting state of the [(Pr 2PCH2CH2CH2PPr 2)Pd(PR3)2] in the catalysis of the reaction of ethene with The size-selective hydrogenation of alkenes by dendrimer-encapsulated palladium nanoparticles has been investigated by NMR spectroscopy. 

Dendrimer-encapstdated catalysts are another area of active research for polymer-supported catalysts. The nanoparticles are stabilized by the dendrimers preventing precipitation and a omeration. Bimetallic nanoparticles with encapsulated metals (dendrimer-encapsulated catalyst DEC) from commercially available fourth-generation PAMAM dendrimers and palladium and platinum metal salts were prepared via reduction by Crooks and co-workers [34], following previous work in this area [35], The simultaneous incorporation of Pt and Pd reflects the concentrations in solution. The bimetallic DECs are more active than the physical mixture of single-metal DEC [35, 36] in the case of the hydrogenahon of allyl alcohol in water, with a maximum TOP of 230 h compared to TOP = 190 h obtained for monometallic palladium nanoparticles (platinum TOP = 50 h ). 

H. Lang, R.A. May, B.L. Iverson, B.D. Chandler, Dendrimer-Encapsulated Nanoparticle Precursors to Supported Platinum Catalysts, Journal of the American Chemical Society 125, 14832, 2003. 

While they are not strictly redox-containing dendrimers. Crooks and Zhao have encapsulated platinum and other metallic nanoparticles inside PAMAM dendrimers. The catalytic properties of these materials have been examined using cyclic voltammetry, and it was found that a gold electrode, modified with large hydroxyl-terminated PAMAM dendrimers containing clusters of 60 platinum atoms, was readily able to catalyze O2 reduction [98]. Similar results have been reported for palladium clusters encapsulated in the same hydroxyl-terminated PAMAM dendrimers [99]. 

Lang HF, May RA, Iversen BL, Chandler BD (2003) Dendrimer-encapsulated nanoparticle precursors to supported platinum catalysts. J Am Chem Soc 125 14832... 

FIGURE 9.3 a) UV-vis spectra of 2.5 0,M Pd3oG4NH2 solutions before (pH 3) and after (pH 8) reduction, b) Time-resolved UV-vis spectra of 2.5 pM PdjoGdNH solutions in the presence of 0.1 M KCl before (pH 3) and after (pH 8) reduction. Reprinted with permission from H. Ye, R.W.J. Scott, R.M. Crooks, Synthesis, Characterization, and Surface Immobilization of Platinum and Palladium Nanoparticles Encapsulated within Amine-Terminated Poly(amidomine) Dendrimers Langmuir 20 (2004) 2915. Copyright 2004 American Chemical Society. 

H. Ye, R.W.J. Scott, R.M. Crooks, Synthesis, Characterization, and Surface Iituno-bilization of Platinum and Palladium Nanoparticles Encapsulated within Amine-Terminated Poly(amidoamine) Dendrimers, Langmuir 20, 2915, 2004. 

Ye HC, Scott RWJ, Crooks RM (2004) Synthesis, characterization, and surface immobilization of platinum and palladium nanoparticles encapsulated within amine-terminated poly(amidoamine) dendrimers. Langmuir 20 2915... 

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