Drying Control Additive: DMF Fluorescence Yield in Sol-gel Materials doped with Rare Earth Impurity Ions Professors Dan Boye (Davidson College Physics Department) and Ann Silversmith (Hamilton College Physics Department) Drying Control Additive: DMF Full Densification Eliminates Rehydration Quenching 5D3 emission from Tb3+ (0.02%Tb and 2%Al in SiO2 glass) is sensitive to the presence of water in the glass. The inclusion of a drying additive (dimethyl formamide, DMF) displaces the water created during the hydrolysis reaction. This removes a non-radiative pathway and so the 5D3 emission is greatly enhanced. 5D3:5D4 ratio 0.2%Al and DMF 0.2%Al no Al 5D3 7FJ 5D4 7FJ The drying agent also provides for a more uniform pore distribution. Internal strains are greatly reduced, allowing full densification of the glass with heat treatment. Water cannot re-enter glass and quench 5D3 emission.