Electrical bistability of CdS nanoparticles sandwiched between aluminum tris (8-hydroxyquinoline) layers

We report the electrical bistability of cadmium sulfide (CdS) nanoparticles (NPs) capped by dodecanethiol, which are sandwiched between aluminum tris (8-hydroxyquinoline) (Alq(3)) layers. The current density-voltage (J-V) characteristics of the device with Al/Alq(3)/CdS NPs/Alq(3)/Al structures show the high- and low-conducting state at the same voltage, and the two states are reproducible by applying different negative sweeping voltages. The Ohmic model and the space-charge limited model are proposed and supported by the current density-voltage results, which give a possible transport mechanism for the electrical bistability of our devices. (C) 2008 Elsevier Ltd. All rights reserved.