Palladium sulfide nanoparticles

In another study, a poly4VP layer was grafted, which was further activated in a PdCl2 solution followed by reaction with CO or H2S to yield composite particles with metallic palladium or palladium sulfide nanoparticles in the shell. 

Schultz and Matijevic (16) prepared nanoparticles of palladium sulfide (PdS) by the continuous double-jet mixing of PdCl2 or Na2(PdCl4) and Na2S. They found that the particle size was 20-30 nm in mean diameter obtained in acidic media (pH = 2-3), but 2-5 nm in alkaline media, probably due to the high equilibrium concentration of sulfide ions S2- by dissociation of H2S and HS in the alkaline media (pH = 10-12). A cationic surfactant, cetyl trimethyl ammonium bromide (CTAB), was found to be useful for stabilizing the small particles prepared in alkaline media. 

It is considered that the stannyl or silyl radical and the alkyl radical are reactive intermediates in these reactions. In contrast to the selective formation of the arylchalcogenosilanes in the above radical reactions, the cross-coupling reaction of a hydrosilane with alkyl(aryl)sulfides catalyzed by palladium nanoparticles results in the selective formation of the corresponding alkylthiosilanes.42... 

Except gold, several other metal nanoparticles, also those of less noble metals, could be prepared, for instance, of silver, palladium, and cobalt, as well as sulfidic species like CdS or PbS. ... 

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