Electric-field-induced charge transfer between gold nanoparticle and capping 2-naphthalenethiol and organic memory cells

An electrical transition, induced by a high electric field, was observed in a device consisting of a polystyrene film containing 2-naphthalenethiol-capped Au nanoparticles sandwiched between two Al electrodes. The current through the device changed from a charge-injection-controlled current to a space-charge-limited current. The latter current is higher than the former by more than three orders of magnitude at 2 V. Asymmetrical current-voltage curve was observed along the two polarity directions for the device after the transition. This transition is attributed to an electric-field-induced charge transfer between the Au nanoparticle and the capping 2-naphthalenethiol. The device exhibits good stability in the high conductivity state, so it can be used as a write-once-read-many times electronic memory. (C) 2005 American Institute of Physics.