Key Words:SURFACTANT-FREE SYNTHESIS; CRYSTAL-STRUCTURE; AU(I)-THIOLATE COMPLEXES; ULTRASENSITIVE DETECTION; GOLD NANOPARTICLES; COLLOIDAL METAL; PHASE-TRANSFER; THIOLATE; CLUSTERS; GROWTH
Abstract:Effective yet versatile synthetic strategies for size-tunable metal nanoclusters (NCs) are scarce. This has hampered the development of this unique class of nanomaterials. Here, a general protocol is reported for the synthesis of high-quality metal NCs protected by a variety of organic ligands (e.g., selenolate, thiolate, and phosphine) based on a miscible-solvent-assisted phase transfer between water and organic solution. This method is demonstrated to be facile, rapid (<= 3 h), scalable (gram-scale), and versatile. The size of the selenolated and thiolated Au NCs can be tuned from Au-10 to Au-61 by simply varying the miscible solvent in proportions and types. The advantages of this method, such as quick phase separation and no need for purification treatment, enable real-time monitoring of metal NC growth within the NaBH4 reduction system. The results show that the size of Au NCs gradually increases with increasing valence electron count by a stepwise 2x e(-) hopping mechanism (x = 0-5), i.e., 0 e(-) -> 2 e(-) -> 4 e(-) -> 8 e(-) -> 18 e(-) -> 22 e(-) -> 32 e(-).
Volume:32
Issue:9
Translation or Not:no