A Luminescent Polysilsesquioxane Obtained by Self-Condensation of Anionic Polyhedral Oligomeric Silsequioxanes (POSS) and Europium(III) Ions

The self-condensation reaction of an anionic completely condensed polyhedral oligomeric silsequioxane (POSS) in the presence of different Eu³⁺ loadings generated an amorphous polysilsequioxane. The synthesis involves self-condensation of POSS units and Eu³⁺ ions and can be carried out at room temperature in a mild acid solution (pH 5.5), followed by simple solvent evaporation under gentle conditions (80 °C). The materials exhibit good chemical integrity, appreciable luminescent properties, and their emission intensity increases by ca. 250 times after inclusion of 1,10-phenanthroline groups in the structure. Furthermore, the final materials showed a very limited photodegradation of ca. 3 % after 1 h of light irradiation. These properties make these samples suitable for applications as sensors and light-emitting components for luminescent devices.