Immobilization of palladium nanoparticles on latex supports and their potential for catalytic applications

Palladium nanoparticles were reduced in the presence of several latex dispe rsions possessing different hydrophobicities. Various reduction methods wer e investigated, specifically the slower methods of refluxing the alcoholic solution and the more rapid reduction by potassium tetrahydridoborate. In s everal cases the latexes showed the ability to adsorb and immobilize the pa lladium nanoparticles on their surface. Transmission electron microscopy wa s employed to show the immobilization of the metal nanoparticles on the lat ex surfaces, and their nanosize dimensions. The latex-metal dispersions sho wed catalytic activity for the hydrogenation of cyclohexene as a model reac tion. A selection of water-soluble protective polymers was included to expl ore whether the metal nanoparticles were still immobilized. In the case of the more hydrophobic latexes, the accumulation and immobilization of the me tal nanoparticles was preserved both before and after their use as hydrogen ation catalysts.