Bimetallic Pd–Au nanocluster arrays grown on nanostructured alumina templates

Bimetallic nanoparticles are becoming increasingly interesting in nanoscience and nanotechnology. They have applications in, for example, catalysis and sensors, high density magnetic storage, and optical filters. However, experimentally it is relatively difficult to obtain homogeneous distributions of bimetallic nanoparticles: not only is their size distribution broad but, of greater concern, their chemical composition is generally non-uniform. For many applications, it is also important that the nanoparticles order in a regular array. Here, we present a new method that allows the generation of a regular two-dimensional array of bimetallic Au?Pd nanoparticles with tunable size and composition. The method provides a unique model for studying size and composition effects in the physical and chemical properties of bimetallic nanoparticles.