Ultrafast Size Expansion and Turn-On Luminescence of Atomically Precise Silver Clusters by Hydrogen Sulfide

The formation of high-nuclearity silver(I) clusters remains elusive and their potential applications are still underdeveloped. Herein, we firstly prepared a chain-like thiolated Ag-I complex {[Ag-18((SBu)-Bu-t)(10)(NO3)(8)(CH3CN)(2)(H2O)(2)] . [Ag-18((SBu)-Bu-t)(10)(NO3)(8)(CH3CN)(6)]}(n) (abbreviated as Ag-18) in which two similar Ag-18 clusters are assembled by NO3- anions. The solution containing Ag-18 reacted with hydrogen sulfide with controlled concentration, promptly producing another identifiable and bright red-emitting high-nuclearity silver(I) cluster, Ag-62(S)(13)((SBu)-Bu-t)(32)(NO3)(4) (abbreviated as Ag-62). We tracked the transformation using time-dependent electrospray ionization mass spectrometry (ESI-MS), UV/Vis absorption and photoluminescence spectra. Based on this cluster transformation, we further developed an ultra-sensitive turn-on sensor detecting H2S gas with an ultrafast response time (30 s) at a low detection limit (0.13 ppm). This work opens a new way of understanding the growth of metal clusters and developing their luminescent sensing applications.

Automated summary

The study successfully prepared high-nuclearity silver(I) clusters Ag-18 and Ag-62, and developed a highly sensitive H2S gas sensor based on their transformation, providing insights into the growth of metal clusters and their luminescent sensing applications.