title: Toward understanding the growth mechanism: tracing all stable intermediate species from reduction of Au(I)-thiolate complexes to evolution of Au₂₅ nanoclusters.
abstract: Despite 20 years of progress in synthesizing thiolated gold nanoclusters (Au NCs), the knowledge of their growth mechanism still lags behind. Herein the detailed process from reduction of Au(I)-thiolate complex precursors to the eventual evolution of and focusing to the atomically precise Au25 NCs was revealed for the first time by monitoring the time evolution of Au(I) precursor and Au NC intermediate species with ESI-MS. A two-stage, bottom-up formation and growth process was proposed: a fast stage of reduction-growth mechanism, followed by a slow stage of intercluster conversion and focusing. Balanced reactions of formation for each identified NC were suggested, backed by theoretical calculations of the thermodynamic driving force. This work advances one step further toward understanding the mechanism of formation and growth of thiolated Au NCs.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore , Singapore 119260.
authors.forename: Zhentao
authors.initials: Z
authors.lastname: Luo
authors.forename: Vairavan
authors.initials: V
authors.lastname: Nachammai
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Ning
authors.initials: N
authors.lastname: Yan
authors.forename: David Tai
authors.initials: DT
authors.lastname: Leong
authors.forename: De-en
authors.initials: DE
authors.lastname: Jiang
authors.forename: Jianping
authors.initials: J
authors.lastname: Xie