First-principles study of size- and edge-dependent properties of MXene nanoribbons
journal contributionposted on 2016-08-29, 00:00 authored by L. Hong, R. F. Klie, S. Öʇüt
We present results and analyses from first-principles calculations aimed at exploring the size- and edge-dependent properties of a wide range of MXene nanoribbons cut from two-dimensional (2D) semiconducting MXenes. The nanoribbons are classified by their edge types (armchair versus zigzag), the composition and sequencing of the terminating atomic lines, and the lowest-energy structural models of their 2D counterparts. The semiconducting versus metallic nature of the nanoribbons is well explained using an electron counting rule for the edge dangling bonds. For semiconducting nanoribbons, the band-gap evolution as a function of ribbon size is shown to be dependent on the lowest-energy structural model, and determined by a combination of factors such as quantum confinement, the energetic location of the edge states, and the strength of the d-d hybridization. Nanoribbons cut from 2D MXenes with asymmetric surfaces are found to have bent ground-state structures with curvatures increasing as the size of the ribbon decreases.
This work was supported by the National Science Foundation (Grant No. DMR-1408427) and used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U. S. Department of Energy under Contract No. DE-AC02-05CH11231.
Publisher StatementThis is a copy of an article published in Physical review B: Condensed matter and materials physics. © 2016 American Physical Society.
PublisherAmerican Physical Society