Catalytic applications of noble metal nanoparticles produced by sonochemical reduction of noble metal ions #11

Abstract

Noble metal nanoparticles have great potential for application as catalysts. Their catalytic properties depend sensitively on the size, structure, and shape of the metal nanoparticles and their combination with support materials. Sonochemistry is a possible approach for the efficient production of powerful noble metal nanoparticle-based catalysts. When an aqueous solution is irradiated by ultrasound, unique chemical effects (radical reactions and thermal reactions) and physical effects (shock waves and micro-jet flow) are simultaneously generated during acoustic cavitation. Inside the bubbles and the gas/liquid interfaces that occur during acoustic cavitation are specific reaction fields that can induce unique chemical reactions. In this chapter, the sonochemical reduction of noble metal ions, the synthesis of noble metal nanoparticles, and their immobilization on support materials are described. The applications of sonochemically prepared nanoparticles to catalytic hydrogenation reactions and photocatalytic reactions are also described. In addition, sonochemical synthesis and its application to noble metal-magnetic nanocomposites and to the catalytic growth behavior of sonochemically synthesized seed particles are introduced.