초록 |
A light-emitting electrochemical cell (LEC) is an innovative device in a simple structure containing a mixture of luminophore and electrolyte sandwiched between electrodes. Here, we report LEC containing an active layer comprising green-emitting InP/ZnSeS quantum dots (QDs) blended with polyvinyl carbozole (PVK) p-type polymer semiconductor along with 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid. The blending of polymer semiconductor boosts the density of holes reaching to QD, leading to emission from QD, which is unattainable without PVK. Moreover, employing zinc oxide nanoparticles layer onto the QDs-PVK-ionic liquid active layer enhances the density of electrons reaching to QDs. The composition of these materials is varied systematically for balancing the injection of electrons and holes into QD. High luminescence of ~632 cd/m2 and high efficiency >1.3 cd/A are achieved, both of which are higher than the values obtained from any previous QDs based LEC. |