Palladium‐catalyzed electroless plating of gold on latex particle surfaces

Abstract

AbstractGold can be deposited onto a latex particle surface via the growth of metal islands with the electroless plating method. A new method is proposed for the electroless plating of gold on the surface of poly(styrene‐co‐vinylimidazole) latex particles, which is catalyzed by palladium present on the latex particle surfaces. The palladium ions are anchored to the latex particle surfaces by the formation of a palladium–imidazole complex, and palladium nanoparticles are nucleated by a reductant. These palladium islands act as catalytic sites, so gold is preferentially deposited onto the latex particle surfaces. Transmission electron microscopy, X‐ray photoelectron spectroscopy, and sucrose density gradient column results indicate that the palladium is associated with the imidazole‐functionalized latex particles. Different gold loading levels and reductant types were explored. Latex particles were partially encapsulated by finely dispersed gold nanoparticles less than 2 nm in diameter or by gold islands with sizes ranging from 10 to 100 nm up to a gold loading level of 3.1 mg of Au/m2 of latex. However, using higher gold loading levels led to uncontrollable electroless plating of gold because gold reduction in the water phase became very dominant even in the presence of catalytic palladium on the latex particle surface. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009