Modélisation des propriétés d'hétérostructures de van der Waals avec un fort couplage intercouche

Modeling the properties of van der Waals heterostructures with strong interlayer coupling

• Auteur / Autrice : Yu Zhang
• Direction : Frédéric Labat
• Type : Projet de thèse
• Discipline(s) : Chimie Physique
• Date : Inscription en doctorat le 02/10/2023
• Etablissement(s) : Université Paris sciences et lettres
• Ecole(s) doctorale(s) : École doctorale Chimie physique et chimie analytique de Paris Centre (Paris ; 2000-....)
• Partenaire(s) de recherche : Laboratoire : Institute of Chemistry for Life and Health Sciences
• Partenaire(s) de recherche : Equipe de recherche : Chimie Théorique et Modélisation (TCM)
• Partenaire(s) de recherche : établissement opérateur d'inscription : Chimie ParisTech / École Nationale Supérieure de Chimie de Paris (ENSCP)

Mots clés

Mots clés libres

Dft

Van der Waals

Hétérostructures

Dft

Van der Waals

Heterostructures

Résumé

The field of two-dimensional (2D) materials has been the subject of numerous studies with various applications targeted in fundamental physics, (opto)electronics, energy and biology. 2D materials refer to thermodynamically stable materials in layers which are just a few atoms thick, which can eventually be stacked together to design heterostructures made of different materials with novel electronic and optical properties. In the so-called van der Waals (vdW) heterostructures, layers are held together by weak vdW forces without direct chemical bonds, allowing to combine different constituent materials easily. Although such vdW heterostructrures can potentially form n-p junctions able to form free charge carriers for photovoltaic applications, the progress in this field remains so far quite limited. This can be related to poor interlayer interactions and limited hybridization between the constituent flakes of the heterostructures, resulting in reduced photoinduced charge generation. To increase the interlayer chemical interaction, natural bonding between the monolayers can be considered as found in the recently discovered 2D triphosphides, with a XP3 chemical formula where X can be a group II (Ca), group III (Al, Ga, In), group IV (Ge, Sn) or group V (As, Sb) element. In this project, we propose to develop a computational protocol essentially based on periodic Density Functional Theory (DFT) to better understand these vertical heterostructures enabling one to design multilayered 2D XP3 with controlled properties.