Mechanism of nonvolatile resistive switching in graphene oxide thin films

The mechanism of the resistive switching (RS) effect in graphene oxide (GO) thin films prepared by the vacuum filtration method has been investigated by macroscopic current-voltage (I-V) measurements and conducting atomic force microscopy (CAFM). Detailed I-V measurements show that in metal/GO/Pt sandwiches, the RS originates from the formation and rupture of conducting filaments. An analysis of the temperature dependence of the ON-state resistance reveals that the filaments are composed of metal atoms due to the diffusion of the top electrodes under a bias voltage. Moreover, the RS is found to occur within confined regions of the metal filaments. The RS effect is also observed in GO/Pt structures by CAFM. It is attributed to the redox reactions between GO and adsorbed water induced by external voltage biases. (C) 2011 Elsevier Ltd. All rights reserved.