Tunable ultraviolet to deep blue light emission from sulfur nanodots fabricated by a controllable fission-aggregation strategy

Bright tunable light emission in the short wavelength range from sulfur nanodots was demonstrated with a photoluminescence quantum yield (PLQY) of up to 59.4%. A fission-aggregation mechanism was proposed for the formation of sulfur nanodots with desired performances. This synthetic strategy allowed for simultaneous size control from 3.2 to 5.6 nm, thus tuning the emission color from ultraviolet (UV) to deep blue (342–430 nm), and for the suppression of unwanted nonradiative recombination centers and deep level emission. The luminescence mechanism and quantum confinement effect of the synthesized sulfur nanodots were investigated by optical spectroscopy and theoretical calculations. These results show promise toward the application of sulfur nanodots in UV optoelectronics, biomedical treatments, and sterilization. [Figure not available: see fulltext.]