Ab initio screening of two-dimensional CuQx and AgQx chalcogenides.
INUI, Guilherme K.; SILVEIRA, Julian Francisco Rama Vieira; DIAS, Alexandre Cavalheiro; BESSE, Rafael; SILVA, Juarez Lopes Ferreira da.
INUI, Guilherme K.; SILVEIRA, Julian Francisco Rama Vieira; DIAS, Alexandre Cavalheiro; BESSE, Rafael; SILVA, Juarez Lopes Ferreira da.
Abstract: Two-dimensional (2D) chalcogenides have attracted great interest from the scientific community due to their intrinsic physical?chemical properties, which are suitable for several technological applications. However, most of the reported studies focused on particular compounds and composition, e.g., MoS2, MoSe2, WS2, andWSe2. Thus, there is an increased interest to extend our knowledge on 2D chalcogenides. Here, we report a density functional theory (DFT) screening of 2D coinage-metal chalcogenides (MQx ), where M = Cu, Ag, Q = S, Se, Te, x = 0.5, 1.0, 1.5, 2.0, with the aim to improve our atomistic understanding of the physical-chemical properties as a function of cation (M), anion (Q), and composition (x). Based on 258 DFT calculations, we selected a set of 22 stable MQx monolayers based on phonons analyses, where we identified 9 semiconductors (7 AgQx and 2 CuQx), with band gaps from 0.07 eV up to 1.67 eV, while the remaining systems have a metallic character. Using all 258 systems, we found a logarithmic correlation between the average weighted bond lengths and effective coordination number of cations and anions. As expected, the monolayer cohesive energies increase with the radius of the Q species (i.e., from S to Te). Furthermore, an increase in the anion size diminishes the work function for nearly all MQx monolayers, which can be explained by the nature of the electronic states at the valence band maximum.
@article={003080894,author = {INUI, Guilherme K.; SILVEIRA, Julian Francisco Rama Vieira; DIAS, Alexandre Cavalheiro; BESSE, Rafael; SILVA, Juarez Lopes Ferreira da.},title={Ab initio screening of two-dimensional CuQx and AgQx chalcogenides},journal={Journal of Physics: Condensed Matter},note={v. 34, n. 30, p. 305703-1-305703-9},year={2022}}