Device Applications of Metal-2D-Materials Interfaces A Short Review

The electronic energy band gaps of 2D-materials are known to spread over a wide range from zero in graphene to > 6eV in hexagonal boron nitride (h-BN). Various combinations of such engineered nanomaterials offer a number of novel device applications involving their unique optical, electronic, and thermal properties along with their higher charge carrier mobilities and saturation limited drift velocities. Structurally, these nanomaterials have single or multiple monolayers stuck together, which are not only suitable for flexible electron devices and circuits but also in preparing heterostructures (lateral as well as vertical configurations) that form super lattices with different kinds of band alignments. Such possibilities offer flexible control over the charge carrier transport in these materials via numerous types of exciton formations. Their extra sensitivity towards the presence of atomic, molecular and nanoparticulate species in their vicinity is the most significant aspect of these 2D-materials. This is the reason behind studying them in detail for detecting the presence of extremely low concentrations of the analyte that are not achievable in conventional sensors. For translating the above-said superlative properties of these fast emerging families of 2-D nanomaterials into usable devices and circuits, applying the conventional device fabrication technologies poses a real challenge. The experimental results reported in the context of forming usable interfaces between a metal and 2D-nanomaterial are examined here to assess their current status and future prospects. Their widespread applications are certainly anticipated in the fields like printed micro/nano sensors, large area electronics and printed intelligence with special reference to their emerging usages in Internet of Things (IoT) in the near future.