Synthesizing Photoluminescent Au28 (SCH2 Ph-t Bu)22 Nanoclusters with Structural Features by Using a Combined Method.

Abstract

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing-ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28 (SCH2 Ph-t Bu)22 with the same number of gold atoms as existing Au28 (SR)20 nanoclusters but different ligands (hetero-composition-homo-size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e., the quasi-linear growth of Au4 -tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6 (SCH2 Ph-t Bu)6 hexamer chair-like rings on the kernel surface were also first reported, which endow Au28 (SCH2 Ph-t Bu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi-ring to the kernel via Au-Au bonds.