Ligand-protected gold nanoclusters have been attracting great interest, because they display aesthetical structural diversity and are promising materials for both fundamental research and applications in catalysis, biosensing, luminescence and molecular electronics, etc. Their precise compositions and well-defined sizes are very helpful for understanding the structure-property relationships of metal clusters and nanoparticles.
Beyond the conventional thiolate and phosphine ligands, alkynyl groups have emerged as a promising ligand in protecting gold nanoclusters. As the ligand space is further broadened, new cluster compositions, structures and interfaces can be discovered. We will provide an atomic-level view of alkynyl-protected gold nanoclusters. The syntheses of a series of gold nanoclusters with “direct reduction” method will be reported. The total structure determination of these clusters will be described. The stability and optical properties of these nanoclusters will be discussed based on electronic structural analysis. In addition, ligand effects on the catalytic performance of gold nanoclusters will be presented. We believe the success in these systems will stimulate more effort in discovering new aspects this class of gold nanoclusters with alkynyl groups in the protective layer.