Electric-field-induced fluorescence quenching in dye-doped tris(8-hydroxyquinoline) aluminum layers

The authors measured electric-field-induced fluorescence quenching (EFIFQ) in both undoped and fluorescent dye-doped tris(8-hydroxyquinoline)aluminum (AlQ3) layers of organic light-emitting devices. Results show that doped AlQ3 layers demonstrate smaller EFIFQ than undoped ones. The phenomenon is attributed to the narrower energy band gap of the guest molecule relative to that of the host material, which makes it less prone to electric-field-induced dissociation of the excited state. Results also show that increasing the concentration of the guest material or decreasing its band gap leads to a decrease in EFIFQ.