Water-soluble silicon quantum dots with wavelength-tunable photoluminescence

The synthesis of highly monodisperse, water soluble Silicon Quantum Dots that permits the fine tuning of emission wavelength, was studied. The study showed the controlled conversion of ̃3nm H-Si QDs to water-soluble, uniform-sized Si QDs of different core sizes through controlled oxidation in EtOH/H₂O₂ solution. The samples, after oxidation under reflux, were passed through a 0.45 μm filter, and clear solutions were collected. The experiment was carried out with the synthesis of H-Si QDs by the POM-assisted electrochemical method, which was then dispersed in ethanol. Transmission electron microscopy (TEM), and fluorescence microscopy was used to get the images. The results showed that the Si QDs, especially the blue emitting one, out of those seven colors, exhibit excellent photocatalytic activity in the visible range.