Synthesis and Optical Properties of Unique Pt₁Ag₂₄ Nanoclusters with Mixed Exterior Motif Structures

The atomic arrangement of metal nanoclusters plays a significant role in the structure-property correlation. Herein, we present a novel Pt₁Ag₂₄(SR)₁₆(PPh₃)₃ nanocluster with a unique structure, different from two reported Pt₁Ag₂₄ nanoclusters. The nanocluster was prepared via one-pot synthesis and solvent extraction. It has a centered icosahedral Pt₁Ag₁₂ kernel and an open shell composed of three Ag₂(SR)₃(PPh₃) staple motifs and a unique trefoil-like Ag₆(SR)₇ motif. The three kinds of Pt₁Ag₂₄ nanoclusters have the same kernel but different shell configurations. The fine-tuning of structures is necessary and significant for the investigation of the relationship of structures and properties. The different UV-vis absorption spectra indicate that the optical properties of three Pt₁Ag₂₄ nanoclusters mainly depend on the exterior shell configuration and the metal-ligand interface. This work provides insights toward growth mechanism and the structure-property correlation of metal nanoclusters.