Electroluminescence as a probe for elucidating electrical conductivity in a deoxyribonucleic acid-cetyltrimethylammonium lipid complex layer

We fabricated an organic light-emitting diode (OLED) using a DNA (deoxyribonucleic acid)-CTMA (cetyltrimethylammonium) lipid complex as an active charge transport layer to elucidate the semiconducting characteristics of the DNA-CTMA complex. From these OLED characteristics, we conclude that a DNA-CTMA layer preferentially transports holes rather than electrons. Furthermore, in using sandwiched device structures with the DNA-CTMA layer, we conclude that the DNA-CTMA layer basically possesses both hole and electron transport abilities and preferentially transports holes due to a shallow lowest unoccupied molecular orbital (LUMO) level that prohibits an efficient electron injection from an adjacent carrier transport layer.