  Graphene is the first truly two-dimensional (2D) material, possessing a
cone-like energy spectrum near the Fermi energy and treated as a gapless
semiconductor. Its unique properties trigger researchers to find more
applications of it, such as high carrier mobility at room temperature, superior
thermoconductivity, high modulus and tensile strength, high transparency, and
anomalous quantum Hall effect. However, the gapless feature limits the
development of graphene nanoelectronics. Making one-dimensional (1D) strips of
graphene (i.e., graphene nanoribbons (GNRs)) could be one of the most promising
approaches to modulating the electronic and optical properties of graphene. The
electronic and optical properties have been theoretically predicted and
experimentally verified highly sensitive to the edge and width. The tunable
electronic and optical properties further imply the possibilities of GNR
application. Recently, the dangling bond problem is under consideration in the
GNR system. Various passivation at the ribbon edge might change the physical
properties. In this work, some passivation conditions are studied, such as
alkalization and hydrogenation.
