Studying of photoluminescence property of carbazole unit based push-pull oligomers

The photoluminescence (PL) property of two push-pull oligomers named C2B and DC2B, comprising of carbazole and difluoroboron β-diketonate units, were probed by many optical tests. A comparison of the PL property of C2B and DC2B indicated that the introduction of carbazole unit red shifted the spectral feature and accelerated PL relaxation rate. Meanwhile, it also accelerated the rate of intramolecular charge transfer (ICT), the reorganization of excited state and relaxation from the ICT state to the ground state, based on the global analysis of transient absorption data. Finally, C2B and DC2B were mixed together and engineered into white light emitting diode test, showing a correlated color temperatures (CCT) value of 4687 K, indicating their potential in the organic displaying devices.