Abstract:
We have systematically studied energetics, structural and electronic properties of
di erent con gurations of the B atoms substituting C-H pairs located on a single hexagonal
ring in a graphane system using the rst-principles density functional theory (DFT). A total
number of 12 distinct B dopants con gurations were identi ed and characterized. Based on
the formation energy analysis, we found that relative stability of B dopants depends greatly on
the defect con gurations. Our results suggest that the B substitutions prefer to be distributed
randomly but avoiding the formation of homo-elemental B-B bonds in a graphane system, at
any concentration. Generally, the values of band gap decrease as the number of B dopants
increases, but the low energy con gurations have large band gaps compared to those that have
homo-elemental bonds. As a result, the band gap of graphane can be ne tuned through
the change in the structural arrangement of B atoms. The adequate control of the electronic
structure of graphane through doping should be essential for technological device applications.
