Gold nanoparticles for applications in energy and environment: synthesis and characterization

Nanometre-size gold displays exceptional physical and chemical properties that depend not only on their sizes but also on their shapes. Here we investigate the growth of size-selected gold nanoclusters and their shapes characterized using both TEM and STEM. It is found that the cluster-substrate interaction influences the height of small nanoclusters Au80, as indicated by comparison between MgO and amorphous carbon substrate, but this effect is overcome by the dynamical landing process at high deposition energy. Moreover, large gold nanoclusters, Au8860 have asymmetric structures with aspect ratio between 1 and 2. The simulation shows that the icosahedral shape observed is significantly lower in energy than the alternatives and is expected to be stable.