Patterned Hydrogenation of Graphene: Magnetic Quantum Dot Array

We design a new class of chemically modified graphenes through selective hydrogenation, which contain an array of triangular carbon domains separated by hydrogenated carbon stripes. By using a density-functional theory method within the generalized gradient approximation in the Perdew-Burke-Ernzerhof functional form, we show that each carbon triangle possesses notable magnetic moment on the edges. The chemically patterned graphene can be also viewed as an array of semiconducting quantum dots, where the hydrogenated carbon stripes play the role of quantum confinement. By adjusting the width of hydrogenated carbon stripes or the length scale of uncoated carbon triangles, the magnetic moment, band gap, and optical properties of the selectively hydrogenated graphene can be tuned.