| Full text | |
| Author(s): |
Total Authors: 3
|
| Affiliation: | [1] Univ Sao Paulo, Sao Carlos Inst Phys, POB 369, BR-13560970 Sao Paulo, SP - Brazil
[2] Univ Fed Sao Carlos, Dept Phys, BR-13565905 Sao Paulo, SP - Brazil
[3] Univ Sao Paulo, Sao Carlos Inst Chem, POB 780, BR-13560970 Sao Paulo, SP - Brazil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | ACS APPLIED ENERGY MATERIALS; v. 2, n. 12, p. 8491-8501, DEC 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
Transition metal dichalcogenides (TMDs) offer a platform for obtaining two-dimensional Materials with excellent properties for diverse applications. However, the exploration of the properties of two-dimensional TMDs based on transition metals from Fe, Co, Ni, and Cu groups is scarce. Therefore, to contribute to the understanding of these materials, we performed a density functional theory investigation of 36 MQ(2) compounds (M = Fe, Co, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, Ag, Au; Q = S, Se, Te), employing for each of them layered and nonlayered crystal structural phases previously reported for TMDs. We found that layered crystal structures are energetically favored for Ni group compounds and that the intralayer octahedral coordination has lower energy than the trigonal prismatic phase for all compositions. The layered phases Fe and Ni group compounds have weak interlayer binding dominated by van der Waals interactions, whereas the remaining materials have high exfoliation energies. We identified 17 semiconductor monolayers among the lowest energy layered phases, with band gaps that vary from 0.45 to 2.62 eV, and their valence and conduction band offsets are mainly determined by the positions of M d-states and Q p-states, which contribute both to the valence and conduction edge states. Semiconductor heterojunctions that can be formed with the stacking of monolayers were mostly classified into type-II band alignments, whereas type-I heterojunctions are more likely formed with Ni group TMDs. Estimates for the power conversion efficiency of solar cells based on the type-II heterojunctions resulted in 10 systems with efficiency >15%, suggesting potential application in photovoltaic devices. This study unveils the understanding of the properties of TMDs of the groups 8-11, paving the way for the design of their van der Waals heterostructures. (AU) | |
| FAPESP's process: | 17/09077-7 - Ab-initio study of the structural, electronic, and optical properties of van der Waals heterostructures |
| Grantee: | Rafael Besse |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 17/11631-2 - CINE: computational materials design based on atomistic simulations, meso-scale, multi-physics, and artificial intelligence for energy applications |
| Grantee: | Juarez Lopes Ferreira da Silva |
| Support Opportunities: | Research Grants - Research Centers in Engineering Program |