How does the electric current propagate through fully-hydrogenated borophene?

We study the electronic transport properties of two-dimensional (2D) fully-hydrogenated borophene (namely, borophane), using density functional theory and non-equilibrium Green's function approaches. Borophane shows a perfect electrical transport anisotropy and is promising for applications. Along the peak- or equivalently the valley-parallel direction, 2D borophane exhibits a metallic characteristic and its current–voltage (I–V) curve shows a linear behavior, corresponding to the ON state in borophane-based nano-switches. In this case, electrons mainly propagate via the B–B bonds along the linear boron chains. In contrast, electron transmission is almost forbidden along the perpendicular buckled direction (i.e., the OFF state), due to its semi-conductor property. Our work demonstrates that 2D borophane could combine metal and semiconductor features and may be a promising candidate for nano-switching materials with a stable structure and high ON/OFF ratio.