pH-Selective Synthesis of Monodisperse Nanoparticles and 3D Dendritic Nanoclusters of CTAB-Stabilized Platinum for Electrocatalytic O2 Reduction

摘要

Noble-metal nanoparticles are of great interest because of their versatility as catalysts,[1] photocatalysts,[2] and sensors,[3] and for their applications in optics,[4a] electronics,[4b] and biological fields.[4c] The optical response[5a],[b] and catalytic reactivity[5c],[d] of nanoparticles depend on their sizes and shapes because reactant molecules form different sorption structures on different surface planes. In addition, the applicability of nanoparticles to particular tasks is dependent on the nature of their surrounding capping materials. Therefore, the ability to form well-controlled sizes and shapes[6] and judicious choices of encapsulating materials[1a] have importantly been considered issues that affect the application of nanoparticles. Many reports have described the effects of various templating/capping materials on the sizes, shapes, and stabilities of nanomaterials.[2b], [7a]-[f] Among the noble metals, nanostructured Pt and its stabilization have been studied intensively.[7e],[f] For instance, formation and characterization of Pt nanoparticle networks were recently reviewed by B?nnemann and co-workers.