Different interactions between a metal electrode and an organic layer and their different electrical bistability performances

Abstract

A new p–π conjugated small molecule, 2-[(pyridin-4-ylmethylene)-amino]-6-(N′-pyridin-4-ylmethylene-hydrazino)-benzo[de]isoquinoline-1,3-dione (2PyNI), was synthesized, characterized and fabricated into memory devices. The device ITO/2PyNI/Au (1) showed volatile memory effect, whereas the device ITO/2PyNI/Al (2) showed write once read many times (WORM) effect. According to theoretical calculations, 2PyNI had different interactions with Au and Al, which produced the different memory behaviors of devices 1 and 2, respectively. In addition, the I–V characteristics of devices 1 and 2 were analyzed in detail with various conduction models. The temperature dependence of the current for the ON state of devices 1 and 2 were measured. Under the irradiation of the UV light (365 nm), device 1 could be switched on automatically when the voltage was fixed at −3.0 V and switched off as the bias was removed.