Ligand-free subnanometre gold metal clusters and their applications

Single and small metal nanoclusters with sizes below the nanometre are opening new avenues in materials science due to their unique physicochemical properties, well-differentiated from the nanoparticle counterparts. In this chapter, the synthesis, characterisation and catalytic, optical and biomedical applications of ligand-free subnanometre gold clusters, perhaps the most representative metal clusters of this kind, will be discussed.