Figure 3. Electro-mechanical characteristics of PVA-based flexible memristors. (a) A photographic image of the PVA-based flexible memristor under a mechanical stress with a bending radius (rb) of 5 mm. (b) Current-voltage characteristics of the flexible device under the bending deformations with rb = 5 mm. (c) Reversible memory performances of the device under the bending stress with rb = 5 mm. (d) Memory retention characteristics of the device investigated under the successive positive and negative bending deformations. The rb value for each deformation was 5 mm. (e) Mechanical endurance characteristics of the device. (f) A photograph showing the test process for transient characteristics of the device. (g) Photographic images recording the dissolution of the device in deionized water at room temperature (300 K).