Atomic and electronic properties of quasi-one-dimensional MoS 2 nanowires
- PDF / 1,040,328 Bytes
- 10 Pages / 584.957 x 782.986 pts Page_size
- 102 Downloads / 161 Views
Silvana Botti Laboratoire des Solides Irradiés, École Polytechnique, CNRS, CEA-DSM, 91128 Palaiseau, France; and European Theoretical Spectroscopy Facility (ETSF), 1348 Louvain-la-Neuve, Belgium
Miguel Alexandre Lopes Marques LPMCN, Université Claude Bernard Lyon I and CNRS, 69622 Villeurbanne, France; and European Theoretical Spectroscopy Facility (ETSF), 1348 Louvain-la-Neuve, Belgium
Ángel Rubio Departamento de Física de Materiales, Facultad de Ciencias Químicas, UPV/EHU, Centro Mixto CSIC-UPV/EHU and Donostia International Physics Center, San Sebastián, Spain
Xóchitl López-Lozano Department of Physics and Astronomy, The University of Texas at San Antonio, San Antonio, Texas 78249-0697 (Received 15 May 2012; accepted 16 October 2012)
The structural, electronic, and magnetic properties of quasi-one-dimensional MoS2 nanowires (NWs), passivated by extra sulfur, have been determined using ab initio density functional theory. The nanostructures were simulated using several different models based on experimental electron microscopy images and theoretical literature. It is found that independently of the geometrical details and the coverage of extra sulfur at the Mo edge, quasi-one-dimensional metallic states are predominant in all the low-energy model structures despite their reduced dimensionality. These metallic states are localized mainly at the edges. However, the electronic and magnetic character of the NWs does not depend only on the S saturation but also on the symmetry configuration of the S edge atoms. Our results show that for the same S saturation, the magnetization can be decreased by increasing the pairing of the S and Mo edge atoms. In spite of the observed pairing of S dimers at the Mo edge, the NWs do not experience a Peierls-like metal–insulator transition.
I. INTRODUCTION
The challenge for research in the area of heterogeneous catalysis is to provide highly active and selective catalysts for important reactions such as hydrodesulfurization (HDS).1–5 Molybdenum disulfide (MoS2) has been one of the most important catalysts used in refineries worldwide for HDS over the past century. Within the last decade, and with the advent of nanotechnology, there has been a renewed interest in this material and, more specifically, in MoS2 nanostructures like triangular nanoclusters,5–11 nanoparticles,12,13 nanotubes,14–17 nanowires (NWs),18–22 nanoribbons,23–30 and nanoplatelets.31–36 The reason is 2-fold: first, such nanostructures have intriguing electronic properties, intrinsically associated with their low dimensionality and the resulting electronic confinement. Second, these novel properties, together with the large surface-to-volume ratio, suggest their use as nanocatalysts with improved a)
Address all correspondence to this author. e-mail: [email protected] This paper has been selected as an Invited Feature Paper. DOI: 10.1557/jmr.2012.355 240
J. Mater. Res., Vol. 28, No. 2, Jan 28, 2013
efficiency. In the last decade, the properties of the MoS2 active surface and low-dimensional MoS2 nanostructures have b
Data Loading...
