Precisely controlled two-dimensional rhombic copolymer micelles for sensitive flexible tunneling devices

Abstract

Nanoscale two-dimensional (2D) organic materials have attracted significant interest on account of their unique properties, which result from their ultrathin and flat morphology. Supramolecular 2D nanomaterials prepared by bottom-up approaches have great potential in the creation of nanoscale devices with various applications, each controlled by the properties of its single-molecular components. Here, we report a uniform and controllable 2D rhombic micelles formed by block copolymers (BCPs) with poly(p-phenylenevinylene) (PPV) as core blocks. The supramolecular 2D nanostructures created in this way and driven by π-π interactions realize the precise separation of the semiconducting and insulating constituents of the constructed BCPs. With a vertical tunneling device design, the 2D rhombic micelles exhibited an on-off current ratio of >104 and a high on-state current density of 6000 A cm−2 as the insulating layer was compressed by a conductive atomic force microscopy (C-AFM) probe. The tunneling device also shows a reproducible sensitivity on a flexible substrate, opening up potential flexible pressure sensor applications for such novel supramolecular 2D nanostructures.