Lighting Up Copper Sulfide Nanoclusters via Thioacetamide Introduction

Atomically precise copper sulfide nanoclusters (Cu–S NCs) are of great interest, yet research on their controllable synthesis methods and luminescent properties remains limited. Herein, we report the syntheses and structures of two novel Cu–S NCs: [Cu 20 S(AT) 8 (dppm) 4 (H) 8 ](ClO 4 ) 2 ( Cu 20 -H ) and [Cu 20 S 3 (AT) 12 (dppm) 2 ](ClO 4 ) 2 ( Cu 20 -S ), (HAT = 1-adamantanethiol, dppm = bis(diphenylphosphino)methane), with Cu 20 -S being the first Cu–S NCs prepared via a sulfide-release approach involving thioacetamide. Both clusters exhibit unique structures with regiospecific organic surface coverage: dppm ligands are distributed at both ends of Cu 20 -H and at one end of Cu 20 -S . The core of Cu 20 -H is chiral with D 2 symmetry, whereas the core of Cu 20 -S exhibits only mirror symmetry. Cu 20 -H is nearly nonemissive, while Cu 20 -S exhibits orange luminescence with a high photoluminescence quantum yield (PLQY) of 23.54% and a long lifetime of 10.08 μs at room temperature. The boost in the brightness of Cu 20 -S can be attributed to its rigid and polar structure, which results from the additional sulfide ions. This work presents a novel approach for constructing Cu–S NCs, enriches the copper cluster family, and provides insights into the luminescent properties of Cu–S NCs.