First-principles investigations of structural, electronic and thermoelectric properties of β-Sb/GeI2 van der Waals heterostructures

• Published in: Journal of computational electronics 2022-06, Vol.21 (3), p.582-589
• Main Authors: Marjaoui, Adil, Ait Tamerd, Mohamed, Diani, Mustapha, El Kasmi, Achraf, Zanouni, Mohamed
• Format: Article
• Language: English
• Subjects: Chemical potential; Density functional theory; Electrical Engineering; Electronic structure; Energy; Energy gap; Energy harvesting; Engineering; Figure of merit; First principles; Graphene; Heat conductivity; Heterostructures; Investigations; Mathematical analysis; Mathematical and Computational Engineering; Mathematical and Computational Physics; Mechanical Engineering; Optical and Electronic Materials; Optoelectronic devices; Room temperature; Seebeck effect; Symmetry; Temperature effects; Theoretical; Thermoelectricity; Transport properties; Two dimensional materials
• ISSN: 1569-8025; 1572-8137
• DOI: 10.1007/s10825-022-01884-y

Two-dimensional materials offer the potential to attain nanoscale optoelectronic and thermoelectric devices. In this paper, the electronic structure and thermoelectric potential of β -Sb/GeI 2 van der Waals (vdW) heterostructures with two different stacking configurations (AA and BA) were investigated using first-principles calculations in the framework of density functional theory combined with the semi-classical Boltzmann theory. Band gaps of 1.25 and 2.18 were extracted from the band structures for the β -Sb and GeI 2 monolayers, respectively. For the AA and BA stacking of the β -Sb/GeI 2 heterostructure, band gaps of 0.86 and 0.75 eV were calculated, respectively. We also analyzed the effect of temperature and chemical potential on transport properties. Interestingly, high electronic figure of merit ZT e values of 6.61 (at 0.067 Ry) and 44.40 (at - 0.037 Ry) were achieved for AA and BA stacking at room temperature, respectively. Moreover, the ZT e increased sharply, showing a giant value of 17.69 (at 380 K) for AA stacking. However, for BA stacking a decreased value of 26.67 (at 420 K) was achieved, which was attributed to the Seebeck coefficient value, indicating very good potential for β -Sb/GeI 2 heterostructures in energy harvesting and solid-state cooling applications.