Keele Research Repository

Using ab initio calculations based on density functional theory, we investigate the effects of vacancies on the electronic and magnetic properties of zigzag SiC nanoribbons (Z-SiCNR). Single (V C and V Si ) and double (V Si V Si and V Si V C) vacancies are observed to induce magnetism in Z-SiCNRs. The presence of a single V Si does not affect the half-metallic behavior of pristine Z-SiCNRs; however, a single V C leads to a transition from half-metallic to metallic behavior in Z-SiCNRs due to the edge Si p orbitals and the atoms surrounding the vacancy. The interactions of vacancies with foreign impurity atoms (B and N) are also investigated, and it is observed that V i N C not only suppresses the oscillatory type magnetism of V Si V C but also retains the half-metallic character of the pristine Z-SiCNRs. The defect formation energies of vacancies can be reduced by substitutional B and N atoms. We believe that ferromagnetism is expected if Z-SiCNRs are grown under suitable conditions.