The fine structure of Pearlman's catalyst.
نویسندگان
چکیده
Pearlman's catalyst, nominally Pd(OH)2/C, is widely used as for hydrogenation reactions and C-C coupling reactions. Contrary to the accepted view, we show that Pearlman's catalyst as prepared and after drying consists of carbon supported (mostly) nano-particulate hydrous palladium oxide capped with a monolayer of hydroxyls hydrogen-bonded to a few layers of water: a core-shell structure of C/PdO/OH/H2O. The conventional formulation Pd(OH)2/C from the macroscopic point of view is ruled-out by the different spectral signatures of surface hydroxyls and stoichiometric hydroxides. We also show that a minor fraction of the palladium is present as a reduced species.
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ورودعنوان ژورنال:
- Physical chemistry chemical physics : PCCP
دوره 17 7 شماره
صفحات -
تاریخ انتشار 2015