Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2014)
    Nanomaterials Tuesday Sessions
       Session NM-TuP

Paper NM-TuP22
DFT Study of Surface Passivation of Silicon Carbide Nanowires by Halogens

Tuesday, December 9, 2014, 4:00 pm, Room Mauka

Session: Nanomaterials Poster Session
Presenter: Luis A. Pérez, Universidad Nacional Autónoma de México
Authors: Miranda, Universidad Nacional Autónoma de México
Trejo, Instituto Politécnico Nacional, México
Cruz-Irisson, Universidad Nacional Autónoma de México
L.A. Pérez, Universidad Nacional Autónoma de México
Correspondent: Click to Email
The use of silicon carbide nanowires (SiCNWs) as chemical sensors stands out among their many possible applications. At present, SiCNWs are usually coated with SiO2. To further extend and customize their applications, surface modification of nanowires (NWs) by different chemical species is one of the feasible ways to achieve it. An insightful understanding of the effects of such passivating functional groups is thus important to understand the electronic properties of surface modified NWs. In this work, by using density-functional calculations, we study the stability and the electronic structure of SiCNWs passivated with halogen atoms such as F, Cl, Br or I, considering different surface covering schemes. We show that the stability of SiCNWs strongly depends on both the passivating element and the percentage of surface covering, in an otherwise fully hydrogen passivated NW. Moreover, when going from the most stable system to the less stable one, the following stability trend is obtained: F-SiCNW> Cl-SiCNW>Br-SiCNW>I-SiCNW>H-SiCNW, which can be attributed to the different electronegativities of the passivating elements considered. Finally, the effects of chemical decoration on the size and nature of the NW band gaps are discussed.