(a) Sol-gel glass synthesized from TREOS precursors. On the left: a bulk sample before the annealing process. The pink color is due to the doping of the glass with Erbium ions. On the right: two slices of glass after the pyrolysis. The dark color is due to carbon residuals (scale is in mm). (b) Photoluminescence of sol-gel silica containing silicon QDs obtained from tetrachlorosilane. The peak emission wavelength can be tuned over most of the visible spectrum by proper tuning of the synthesis conditions.
