Investigation on resistive random access memory application of controllable oxidized Ti3C2Tx by heat treatment

The applications of the inevitable oxidation of Ti3C2Tx MXene have been studied extensively recently. In this paper, we report on the resistive random access memory (RRAM) application of controllable oxidized Ti3C2Tx by heat treatment at room temperature, 200, 300, and 400 °C. Through characterization by scanning electron microscopy, x-ray diffraction, Raman spectroscopy, and x-ray photoelectron spectroscopy, it is found that the proportion of TiO2 increases in the TiO2/Ti3C2Tx hybrid with increasing annealing temperature and that Ti3C2Tx was almost completely oxidized to form TiO2 at 400 °C. The oxidized Ti3C2Tx was then fabricated as the active layer sandwiched between the Au top electrode and the ITO bottom electrode in a vertical memory device. The Ti3C2Tx oxidized at room temperature exhibited no hysteresis memory window while Ti3C2Tx oxidized at 300 °C for 1 h demonstrated a larger ratio of Ion/Ioff. It can be concluded that the optimal ratio of TiO2 and Ti3C2Tx annealed at 300 °C contributes to an improved resistive switching memory window. The corresponding gradual I–V curve demonstrates potential for application in the field of neuromorphic computing. The RRAM device fabricated by Ti3C2Tx oxidized at 400 °C for 2 h displays a butterfly shape and negative differential resistance (NDR) phase, which is due to the presence of amorphous TiO2. The NDR regime can be used for the oscillator’s applications. Our work provides an innovative strategy for developing multi-functional applications of partially oxidized Ti3C2Tx by heat treatment.