Half metallicity in BC2)N nanoribbons: stability, electronic structures, and magnetism.

Nanoribbons are suggested to be among the most promising candidates being considered as building blocks in future electronics. In this study, we use density functional calculations to examine the structures and electronic properties of BC(2)N nanoribbons with bare zigzag-shaped edges (zz-BC(2)NNRs). Four different types of atomistic edge configurations are considered, including ribbons terminated with two C edges, B and N edges, B an C edges, and C and N edges. We find the existence of half-metallicity in the ground state of the zz-BC(2)NNRs with two bare C edges and with bare C and N edges. The other two configurations of the zz-BC(2)NNRs can be either semiconducting or metallic, depending on the specific configuration. We also find that the stability of the zz-BC(2)NNRs are largely dependent on ribbon width. The zz-BC(2)NNRs become energetically more stable when the nanoribbon width exceeds 3.3 nm. It is interesting to find that half-metallic zz-BC(2)NNRs with a width of 0.7 nm are thermodynamically more stable than either metallic or semiconducting counterparts. Therefore, the possibility of synthesizing half-metallic zz-BC(2)NNRs exists.