Spectroscopic properties of coumarin 2 in HCl and HNO3 catalysed sol–gel glasses

Laser dye Coumarin 2 (C2) was incorporated in transparent xerogel via acid catalysed sol–gel method. Two different methods using HCl and HNO3 as catalysts were employed. The absorption and fluorescence spectra of C2 in both types of solids show different characteristics. These spectroscopic properties of C2 were compared with its respective properties in ethanolic solution in acidic environment. Solids prepared by using HNO3 as catalyst show superior absorption/emission properties than those prepared by using HCl.