Flexible Memristive Device Based on WSe2 Quantum Dots Sandwiched Between Two Poly (Methyl Methacrylate) Layers

Abstract

In this letter, we demonstrate the fabrication of flexible memristive devices using tungsten di-selenide (WSe2) quantum dots (QDs) as the active layer. The WSe2 QDs were synthesized by facile two-step technique consisting of solvothermal and sonication processes to utilize the charge-trapping sites in the memristive devices. The sizes of as-synthesizedWSe2 QDs, as determined from the transmission electron microscopy image, were in the range between 3 and 5 nm. Current–voltage(I−V) curves for the flexible memristive devices based on nanocomposites consisting of WSe2 QDs sandwiched between two poly (methyl methacrylate) (PMMA) layers showed remarkable bi-stable behavior before and after bending. The ON/OFF ratio of the memory devices before and after bending were approximately1×102 and 1×102, respectively.The devices showed the nonvolatilememory effect with a retention time of more than 7 × 102s. The endurance number of ON/OFF switching cycles for the devices was 1 × 102. The bipolar resistive switching behavior was described on the basis of the I − V results by analyzing the effect of space charge.