The synthesis, characterization, and catalytic activity of PdRh G4-NH2 dendrimer encapsulated nanoparticles (DENs) was studied. To test catalytic activity, kinetic trials were performed for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol in the presence of NaBH4. This reaction can easily by monitored by UV-Vis spectroscopy due to the strong absorption peak of 4-NP at 400 nm, that decreases as the reaction progresses. In the presence of a large excess of NaBH4, the reaction is pseudo first order with respect to 4-NP, and therefore the rate constant can be calculated according to first order kinetics. The reaction was catalyzed with PdRh DENs composed of different ratios of the two metals. The following five ratios were tested, keeping to overall ratio of metal to dendrimer constant at 55: Rh55, Pd15Rh40, Pd27.5Rh27.5, Pd40Rh15, Pd55. The source of palladium was the salt K2PdCl4 and the source of the rhodium was RhCl3. For synthesis, the appropriate molar excess of each metal added to the PAMAM dendrimer templates, stirred to allow complexation of metal to dendrimer, and then reduced with a 10-molar excess of NaBH4 to form bimetallic nanoparticles within the dendrimer. Kinetic trials were then run for each ratio of bimetallic DENs to find the average rate constants, k. These rate constants will determine which metal ratio is the most effective catalyst for the reduction of 4-nitrophenol.

Catalytic chracterization of PdRh dendrimer-encapsulated nanoparticles in the reduction of 4-nitrophenol

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.