Europium(III) tetrakis b-diketonate complexes as luminescent ionic liquids

Light-emitting materials are indispensable nowadays due to their vast range of use and applicability, among them, luminescent soft materials can provide improved luminescence performance and enhanced photochemical stability. These materials can be formed from ionic liquids (ILs) based on lanthanide (Ln³⁺) complexes, which combine features of ILs with the photoluminescent properties of Ln³⁺ complexes. This work aims to investigate the structure and photoluminescent properties of ILs based on Eu³⁺ tetrakis beta-diketonate complexes. The anionic complex [P₆₆₆₁₄][Eu(hfa)₄] was successfully synthesized and characterized. This complex could be classified as a room-temperature ionic liquid and exhibited interesting photoluminescent properties, which were investigated by luminescence and Raman measurements as a function of temperature.