Molecular Sieve-Assisted Inclined Growth of Ultrathin Nonlayered Cr2O3 Nanosheets for Reconfigurable Dual-Mode Memristive Switching

Two-dimensional materials show great potential as candidates for next-generation memristors. However, research on reconfigurable memristors essential to complex in-memory computing frameworks remains underexplored. Here, to tackle this challenge, a reliable vapor-phase growth method is developed to grow ultrathin nonlayered Cr 2 O 3 nanosheets and enable their use in memristors with reconfigurable dual-mode memristive switching. The Cr 2 O 3 nanosheets were inclined-grown on a SiO 2 /Si substrate with tailored thickness from 5.9 to 40 nm and tunable lateral size from 3 to 36 µm by a molecular sieve-assisted strategy. Benefiting from the inclined growth characteristics, the nanosheets can be transferred to arbitrary substrates by simple and quick mechanical pressing without any chemical etching contamination. The constructed Ag/Cr 2 O 3 /Au memristor shows reversible modulation between volatile threshold switching and nonvolatile bipolar operation through compliance-current control. The resulting memristor also demonstrates a low threshold voltage of ∼0.35 V with good cycle-to-cycle and cross-device reproducibility in the volatile regime, together with low set/reset voltages around 1.0 V/−0.55 V and a representative ON/OFF ratio exceeding 10 6 in the nonvolatile regime. This dual-mode functionality originates from an Ag-filament-dominated mechanism assisted by intrinsic defects in Cr 2 O 3 , where limited filament growth yields volatile relaxation behavior, while robust filament bridging stabilizes nonvolatile states. These results reveal the potential of Cr 2 O 3 nanosheets as a promising platform for multifunctional memristive applications.