Photoluminescence carrier transport

Similar to the europium complexes, the terbium complexes used as good emitters in OLEDs also need to have high photoluminescent efficiencies, good carrier transporting properties, and sufficiently good thermal stability for small molecule materials to form a film by thermal evaporation in vacuum. 

Xin, H., Shi, M., Zhang, X.M., et al. (2003) Carrier-transport, photoluminescence, and electroluminescence properties comparison of a series of terbium complexes with different structures. Chemistry Materials, 15, 3728-3733. 

Fig. 9. Quantum confinement effect [22] in the electroluminescence solid line), photoluminescence (dashed line) and absorption (dotted line) of nanocrystals of three different diameters. The blue shift of the (49,42.5 and 33.5 A) electroluminescence in respect to the photoluminescence may be due to trap filling by carriers injected into the CdSe multilayer or to a charge transport mechanism in the CdSe multilayer...

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