High-Efficient Organic Light-Emitting Diodes Using Indium Tin Oxide Treated by KMnO₄ Solution as Anode

High-efficient organic light-emitting diodes (OLEDs) with indium-tin-oxide (ITO) anode treated by KMnO₄ solution are demonstrated. The performance of the OLEDs depends on the concentration of KMnO₄ solution and time of ultrasonic treatment. The OLED whose ITO anode was treated by ultrasonic in KMnO₄ solution with concentration of 50mg/L for 15min displays the best performance. It has higher electroluminescent brightness and lower turn-on voltage than those of traditional devices. In particular, its efficiency can be increased by approximately 40%. The surfaces of the ITO anode with and without treating are analysed by scanning electron microscopy.