Size tunable visible luminescence from individual organic monolayer stabilized silicon nanocrystal quantum dots

Quantum confinement in nanostructured silicon can lead to efficient light emission. However, the photoluminescence (PL) lifetimes in nanostructured silicon are typically very long-approximately 3 orders of magnitude longer than those of direct band gap semiconductors. Herein, we show that organic monolayer coated silicon nanocrystals ranging from 1 to 10 nm in diameter emit with nanosecond-scale lifetimes and high quantum yields, making it possible to measure the PL spectra of single SI quantum dots. The Si quantum dots demonstrate stochastic single-step blinking behavior and size-dependent PL spectra with line widths approximately only three times greater than those measured for CdSe nanocrystals at room temperature.