The dynamics of triplet recombination in fluorene trimers have been studied using steady state photoinduced absorption (PA) spectroscopy. We investigated two type of oligomeric films, deposited by different techniques: thermal evaporation and spincoating. The different molecular arrangement in both films is manifested in a red-shift of the absorption, PL and T1-Tn triplet PA spectra of the sublimated film relative to the spincoated one. Triplet recombination dynamics follow a dispersive bimolecular recombination model away from the trap filling regime. Moreover we report on the characteristics of a host-guest lasing system obtained by co-evaporation of the most promising oligofluorene derivative (T3) with the red-emitter 4-(dicyanomethylene)-2-methyl-6-(p- dimethylaminostyryl)-4H-pyran dye (DCM). The blend satisfies the necessary condition for an efficient FÖrster energy transfer to take place from T3 matrix to DCM molecules.
Oligofluorene derivative in a host-guest system with a red-emitter: Molecular packing effect on the host bimolecular recombination and guest ASE threshold reduction / Cabanillas-Gonzalez, J.; Toffanin, S.; Capelli, R.; Wong, K. -T.; Muccini, M.. - 7051:(2008), p. 70510T. (Intervento presentato al convegno Organic Light Emitting Materials and Devices XII tenutosi a San Diego, CA, usa nel 2008) [10.1117/12.795873].