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Title: Influence of strain and metal thickness on metal-MoS{sub 2} contacts

MoS{sub 2} and other transition metal dichalcogenides are considered as potential materials in many applications including future electronics. A prerequisite for these applications is to understand the nature of the MoS{sub 2} contact with different metals. We use semi-local density functional theory in conjunction with dispersion corrections to study the heterostructures composed of Pd and Pt monolayers with (111) orientation grown pseudomorphically on MoS{sub 2}(001). The interface properties are mapped as a function of the number of deposited overlayers, as well as a function of tensile and compressive strains. Although we show that the dependence of the contacts on strain can be fully explained using the d-band model, we find that their evolution with the number of deposited metal layers is markedly different between Pd and Pt, and at variance with the d-band model. Specifically, the Pt/MoS{sub 2} heterostructures show an anomalous large stability with the deposition of two metal monolayers for all investigated strains, while Pd/MoS{sub 2} exhibits a similar behavior only for compressive strains. It is shown that the results can be rationalized by accounting for second-nearest-neighbor effect that couples MoS{sub 2} with the subsurface metal layers. The underpinnings of this behavior are attributed to the larger polarizabilitymore » and cohesive energy of Pt compared to Pd, that leads to a larger charge-response in the subsurface layers.« less
Authors:
 [1]
  1. Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States)
Publication Date:
OSTI Identifier:
22419868
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; COMPARATIVE EVALUATIONS; DENSITY FUNCTIONAL METHOD; DEPOSITION; DEPOSITS; DISPERSIONS; INTERFACES; LAYERS; MOLYBDENUM SULFIDES; POLARIZABILITY; STABILITY; STRAINS; THICKNESS; TRANSITION ELEMENTS