Incorporation of a liquid crystal to enhance the luminescence properties of Langmuir–Blodgett films of OC1OC6-PPV

The control of molecular architecture provided by the Langmuir–Blodgett (LB) method allows one to obtain enhanced luminescence properties in polymer films, which can be exploited in polymer light emitting diodes (PLEDs). In this study, we show that incorporating a liquid crystal (LC) (PCH302/304) into poly-(2-methoxy-5-hexyloxy-p-phenylene-vinylene) (OC1OC6-PPV) in LB films leads to a 4-fold increase in photoluminescence and 2-fold increase in electroluminescence for (ITO/OC1OC6-PPV(LC5%)/Al) devices for emission at 585 nm, with the current vs. voltage (I vs. V) characteristics exhibiting a typical behavior of rectifying diode. The enhanced luminescence was attributed to an efficient separation of emitting OC1OC6-PPV units induced by the LC in the LB film, which were less ordered than LB films from neat OC1OC6-PPV.