A water soluble inorganic molecular oxide as a novel efficient electron injection layer for hybrid light-emitting diodes (HyLEDs)

作者：Palilis Leonidas C^*; Vasilopoulou Maria; Georgiadou Dimitra G; Argitis Panagiotis

来源：Organic Electronics, 2010, 11(5): 887-894.

DOI：10.1016/j.orgel.2010.02.004

• Hybrid light-emitting diodes (HyLEDs)
• Polyoxometalate (POM)
• Electron injection layer
• Built-in potential

We demonstrate that electron injection in single-layer polyfluorene based polymer light-emitting diodes (PLEDs) can be significantly enhanced by inserting a thin (<10 nm) inorganic polyoxometalate (POM) molecular oxide layer between the polymer layer and an aluminum cathode. Hydrophilic POM was spin-cast from methanol, an orthogonal solvent with regard to the hydrophobic polymer layer underneath, to form the thin cathode interfacial/electron injection layer. A lower turn-on and operating voltage and a higher luminance and current density was obtained in the POM-modified hybrid LEDs (HyLEDs) which are associated with the electron injection barrier reduction in the modified polymer/Al interface, evidenced by the increased open circuit voltage from photovoltaic measurements. These results demonstrate the potential of polyoxometalates as novel, stable cathode interfacial layers for efficient electron injection/transport in high performance HyLEDs.

• 出版日期2010-5