Gold Doping of Silver Nanoclusters: A 26-Fold Enhancement in the Luminescence Quantum Yield

A high quantum yield (QY) of photoluminescence (PL) in nanomaterials is necessary for a wide range of applications. Unfortunately, the weak PL and moderate stability of atomically precise silver nanoclusters (NCs) suppress their utility. Herein, we accomplished a 26-fold PL QY enhancement of the Ag-29(BDT)(12)(TPP)(4) cluster (BDT: 1,3-benzenedithiol; TPP: triphenylphosphine) by doping with a discrete number of Au atoms, producing Ag29-xAux(BDT)(12)(TPP)(4), x=1-5. The Au-doped clusters exhibit an enhanced stability and an intense red emission around 660nm. Single-crystal XRD, mass spectrometry, optical, and NMR spectroscopy shed light on the PL enhancement mechanism and the probable locations of the Au dopants within the cluster.