Electron injection from bis(4-dimethylaminophenyl)squaraine into (4-butoxycarbonyl-9-fluorenylidene)-malononitrile

The injection of photo-excited electrons from bis(4-dimethylaminophenyl)-squaraine into (4-butoxycarbonyl-9-fluorenylidene)malononitrile was studied by using the xerographic discharge technique. The present study has demonstrated for the first time that electrons can be injected from a squaraine into an electron transport layer. The photoinjected current data, analysed in terms of Schottky emission model, indicate that the injection barrier height at the squaraine/BCMF interface is 0.24 eV.