Resistive switching and activity-dependent modifications in Ni-doped graphene oxide thin films

The resistive switching (RS) mechanism in Ni-doped graphene oxide (GO) devices is studied. We found that RS depends strongly on the fabrication method of the GO sheet and on the electrode material. Resistive switching in GO-devices can be caused by the diffusion of ions from metallic electrode or by the migration of oxygen groups, depending on the fabrication process. We also show that GO-based structures possess activity-dependent modification capabilities, emphasized by the increase/decrease of device conductance after consecutive voltage sweeps of opposite polarity. Our results allow a better understanding of bipolar RS, towards future non-volatile memories and neuromorphic systems.