Highly flexible superconducting films with metal-decorated composite 2D materials

Graphene forms an ideal platform to realize macroscopic hybrid materials by direct physisorption of electronically-active adsorbates on top of the high-mobility bidimensional (2D) gas of charge carriers. Here, we demonstrate a novel composite multilayer based on a thin polymer film covered with a monolayer of CVD graphene on top of which a thin layer of tin is evaporated. The metal film shows dewetting and forms a self-organized network of metal nanodots electronically coupled to the graphene. The resulting macroscopic multilayered structure is a highly flexible, stable, and processable composite 2D material that exhibits tunable superconductivity at low temperature. The superconducting properties of the macroscopic composite extend over the full sample size (several square centimeters) and are comparable to the ones of a mesoscopic array of Josephson junctions prepared with similar materials. It provides an upscaling of the concept that is useful for flexible electronics.