We report the unusual generation of near-infrared (near-IR) electrochemiluminescence (ECL) from water-soluble Au nanoclusters (NCs), of which the photoluminescence is primarily within the visible wavelength region. The near-IR ECL is ascribed to the Au(0)-glutathione motif in the Au NCs stabilized by glutathione in water.

We report a method for universal assembly of multiple nanoparticles with different sizes and compositions on a single chemically converted graphene sheet with good control over particle sizes in the range of 1 to 2 nm through the covalent immobilization of dendrimer-encapsulated nanoparticles.

Direct evidence for the blue luminescence of gold nanoclusters encapsulated inside hydroxyl-terminated polyamidoamine (PAMAM) dendrimers was provided by spectroscopic studies as well as by theoretical calculations. Steady-state and time-resolved spectroscopic studies showed that the luminescence of the gold nanoclusters consisted largely of two electronic transitions. Theoretical calculations indicate that the two transitions are attributed to the different sizes of the gold nanoclusters (Au8 and Au13). The luminescence of the gold nanoclusters was clearly distinguished from that of the dendrimers.