Metallophthalocyanine and subphthalocyanine films as electron-transport layer in organic light-emitting diodes

Organic light-emitting diodes (OLEDs) are fabricated by using metallophthalocyanine and subphthalocyanine as electron-transport materials. The performance of the electroluminescence in the device ITO/CoPc/NPB/Alq 3 /TPBi/Pcs/Mg: Ag is systematically investigated. The turn-on voltage, maximum luminance and maximum current efficiency of the device with a SnPc electron-transport layer can reach 7.6 V, 7550 cd/m 2 and 3.26 cd/A, respectively. Meanwhile, the turn-on voltage, maximum luminance and maximum current efficiency of the device with a SubPc layer are 5.4 V, 10059 cd/m 2 , and 6.4 cd/A. The results demonstrate that a relatively unique feature of Subphthalocyaninethe, which could transport electron effectively, and tell us that central metal atoms determined the electron-transport ability of metallophthalocyanine.