Study of energy transfer from excited TPD to Alq in organic electroluminescent devices by time-resolved fluorescence spectroscopy using a scanning near-field optical atomic force microscope

Luminescent properties of a novel fluorene organic material

The photo-physical properties of 6,6'-(9H-fluoren-9,9-diyl)bis(2,3-bis(9,9-dihexyl-9H-fluoren-2-yl)quinoxaline) (BFLBBFLYQ) and its blend doped with N'-biphenyl-N,N'-bis-(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD) were investigated. The absorption, photoluminescence (PL) and electroluminescence (EL) properties of pristine BFLBBFLYQ and blend in solution and spin-coated film are outlined, including a discussion of charge-transfer (CT) exciplex emission of BFLBBFLYQ:TPD blend in the solid state. The luminescent properties of BFLBBFLYQ films using different deposition processes were studied. It was found that the low-energy emission bands at 530-570 nm appeared in the PL spectra of BFLBBFLYQ evaporated films in ultra-high vacuum. Also, the low-energy band was the exclusive emission in the EL spectra of BFLBBFLYQ films.