TITLE:
Enhancement of Performance of Organic Light Emitting Diodes by Using Ti- and Mo-Oxide Nano Hybrid Layers
AUTHORS:
Nguyen Nang Dinh, Do Ngoc Chung, Tran Thi Thao, Tran Thi Chung Thuy, Le Ha Chi, Vo-Van Truong
KEYWORDS:
Organic Light Emitting Diodes (OLED); Hybrid Heterojunctions; Curent-Voltage (I-V) Characteristic; Luminous Efficiency
JOURNAL NAME:
Materials Sciences and Applications,
Vol.4 No.4,
April
30,
2013
ABSTRACT: Nanorod-like TiO2 (nc-TiO2) and MoO3 (nc-MoO3) films were thermally grown from Ti- and Mo-metallic wafers. Nanohybrid films of N,N’-diphenyl-N,N’-bis(1-naphthyl)(1,1’-biphenyl)-4,4’diamine (NPB)/TiO2 and NPB/MoO3 used as anode/hole transport layer (HTL) heterojunctions in blue organic light emission diodes (OLEDs) were prepared by coating NPB onto the nc-TiO2 and nc-MoO3 and TiO2. Characterization of the nanostructured hybrid layers showed that both the photoluminescent property and current-voltage (I-V) characteristics of the hybrid materials were significantly enhanced in comparison with the standard NPB polymer. The electroluminous efficiency of the hybrid devices was considerably enhanced in comparison with the standard device. This suggests a useful application for fabricating “reverse” OLEDs, where the emission light goes-out through the semitransparent cathode, instead of the indium tin oxide (ITO) anode. For this, the ohmic contacts of conducting wires to metallic electrodes can be made much better than to ITO anodes.