摘要
Degradation phenomenon and poor stability of tris(8-hydroxyquinoline) aluminum(Ⅲ)(Alq3)-based organic light-emitting diodes(OLEDs) have attracted much attention. In this paper, we discussed the origin of instability of the facial Alq3-based blue luminescent OLEDs with the help of first-principles calculation. The results show that environmental humidity seriously affects the luminescence stability of Alq3-based OLEDs. H20 molecules in envi- ronment can be firmly bound to the oxygen atoms of the facial Alq3, which then act as starting points for further de- gradation of Alq3. Moreover, the interactions between facial Alq3 and different cathode metal layers were investigated to explain the experiment phenomenon. A design guideline for diminishing the strong attraction from oxygen atoms can be proposed to protect Alq3 and improve the stability of materials applied in OLEDs.
Degradation phenomenon and poor stability of tris(8-hydroxyquinoline) aluminum(Ⅲ)(Alq3)-based organic light-emitting diodes(OLEDs) have attracted much attention. In this paper, we discussed the origin of instability of the facial Alq3-based blue luminescent OLEDs with the help of first-principles calculation. The results show that environmental humidity seriously affects the luminescence stability of Alq3-based OLEDs. H20 molecules in envi- ronment can be firmly bound to the oxygen atoms of the facial Alq3, which then act as starting points for further de- gradation of Alq3. Moreover, the interactions between facial Alq3 and different cathode metal layers were investigated to explain the experiment phenomenon. A design guideline for diminishing the strong attraction from oxygen atoms can be proposed to protect Alq3 and improve the stability of materials applied in OLEDs.
基金
Supported by the National Natural Science Foundation of China(Nos.61307119, 61235004).