Silicon Nanocrystals Functionalized with Pyrene Units: Efficient Light-Harvesting Antennae with Bright Near-Infrared Emission

Pyrene chromophores were attached to silicon nanocrystals (SiNCs) with diameters of 2.6 and 5.0 nm to provide light-harvesting antennae for enhanced optical absorption. Efficient energy transfer from the pyrene moieties to the SiNCs was observed to induce bright visible (2.6 nm) or near-infrared (NIR) (5.0 nm) photoluminescence (PL). The 5.0 nm diameter pyrene-derivatized SiNCs exhibited NIR PL emission that was insensitive to dioxygen, with a 40% quantum yield and long lifetime (hundreds of mu s).