0000000000462550
AUTHOR
Takeo Akatsuka
Dynamically Doped White Light Emitting Tandem Devices
Solution-processed, salt-containing, blue and orange light-emitting layers lead to efficient white light-emitting devices when arranged in a tandem configuration separated by a thin metal layer.
Engineering Charge Injection Interfaces in Hybrid Light-Emitting Electrochemical Cells
Light-emitting electrochemical cells (LECs) consists of a thin film of an ionic organic semiconductor sandwiched between two electrodes. Because of the large density of ions, LECs are often reported to perform independently on the electrodes work function. Here we use metal oxides as charge injection layers and demonstrate that, although electroluminescence is observed independently of the electrodes used, the device performances are strongly dependent on the choice of the interface materials. Relying on metal oxide charge injection layers, such hybrid devices are of interest for real lighting applications and could pave the way for new efficient, stable, low-cost lighting sources.
Temperature Effect of Ionic Transition Metal Complex Light-Emitting Electrochemical Cells
ABSTRACTLight-Emitting Electrochemical Cells (LECs) consist of solution processable ionic light-emitting materials and use air stable electrodes. Their operational mechanism relies on both ionic and electronic conduction. The dynamic behavior is primarily determined by the ionic conductivity. Here, we demonstrate that with increasing temperature the LECs turn-on faster yet without decreasing the efficiency. This is due to the activation energy of ionic transport and the temperature independent photoluminescence quantum yields.