Solution processed Ti3C2 MXene nanosheets as resistive switching layers in flexible RRAM devices for sustainable electronics

Due to their exceptional chemical stability and tunable chemical properties particularly the interlayer bonding, MXenes have emerged as promising switching layers in RRAM devices. This work presents the synthesis of nanosheets of a widely explored MXene (Ti3C2), and its application for demonstrating high performance flexible RRAM devices through solution processing, which is rarely demonstrated till date. The structural and morphological properties of Ti3C2 nanosheets were comprehensively investigated using various characterization techniques. RRAM devices were fabricated on ITO coated PET substrate with both Ag and Al as top electrodes (TE). The Ag/Ti3C2/ITO RRAM devices showed excellent retention time of 10^4 seconds with ION/IOFF of ~10^3 and low average VSET & VRESET voltages of ~0.8 V &- 0.7 V suitable for low voltage operation. On the other hand Al/Ti3C2/ITO RRAM devices exhibited similar excellent retention time of 104 seconds and reliable switching characteristics with higher ION/IOFF of ~10^4, yet a high VSET of 3.5 V and low VRESET of -0.85 V. These devices were further investigated for stability of electrical performance upon bending at various radii of 12 mm, 7 mm, and 5 mm, indicating consistent switching. Among the two, the Al/Ti3C2/ITO device exhibited superior mechanical flexibility, maintaining a higher ION/IOFF (~10⁴–10⁵) and stable retention of both LRS and HRS under bending radii down to 5 mm, whereas the Ag/Ti3C2/ITO device showed a noticeable decline in HRS stability and ION/IOFF (from ~10^3 to ~10^1), indicating the Al-based device is more feasible for flexible memory applications. These findings confirm that solution-processed Ti3C2 can be a promising switching layer for flexible and sustainable electronics.