Luminescent Ionogels Based on Europium-Doped Ionic Liquids Confined within Silica-Derived Networks

Luminescent ionogels were prepared by doping an europium(III) tetrakis β-diketonate complex into an imidazolium ionic liquid, followed by immobilization of the ionic liquid by confinement in a silica network. The ionogels were obtained by a non-hydrolytic method as perfect monoliths featuring both the transparency of silica and the ionic conductivity performances of ionic liquids. The ionogels contain 80 vol % of ionic liquid. The organic−inorganic hybrid materials showed a very intense red photoluminescence under ultraviolet irradiation. The red emission has a very high coloric purity.