Abstract
The stability of Pd dendrimer-encapsulated nanoparticles (DENs) in air-, N2-, and H2-saturated aqueous solutions is reported. The DENs consisted of an average of 147 atoms per sixth-generation, poly(amidoamine) dendrimer. Elemental analysis and UV-vis spectroscopy indicate that there is substantial oxidation of the Pd DENs in the airsaturated solution, less oxidation in the N2-saturated solution, and no detectable oxidation when the DENs are in contact with H2. Additionally, the stability improves when the DEN solutions are purified by dialysis to remove Pd 2+-complexing ligands such as chloride. For the air- and N 2-saturated solutions, most of the oxidized Pd recomplexes to the interiors of the dendrimers, and a lesser percentage escapes into the surrounding solution. The propensity of Pd DENs to oxidize so easily is a likely consequence of their small size and high surface energy.
Original language | English (US) |
---|---|
Pages (from-to) | 10279-10284 |
Number of pages | 6 |
Journal | Langmuir |
Volume | 25 |
Issue number | 17 |
DOIs | |
State | Published - Sep 1 2009 |
Externally published | Yes |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces
- Spectroscopy
- Electrochemistry