Rhodamine 6G-SiO2 hybrids: A photoluminescence study

Photoluminescence properties of Rhodamine 6G dye confined in porous silica are reported. Different types of organic-inorganic hybrids have been prepared and characterized: class I and II systems have been investigated as a function of rhodamine 6G concentration. Samples have been prepared by the sol-gel technique, introducing the organic molecules at the sol stage of the process, or by loading commercial porous silica samples with rhodamine 6G ethanol solution. A comparative analysis on the photoluminescence properties have been performed in order to investigate host-guest chemical-physical interactions and to assess the feasibility of solid state dye lasers. The peak position of the photoluminescence red shifts by increasing the organic molecule concentration. In the investigated range, samples with 5 × 10−4 mole of rhodamine 6G showed the larger emission. By comparing the peak position of the different samples to the one of the ethanolic solution of rhodamine 6G we individuated the class II systems as the most promising composites for optoelectronic applications.