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Electronic and Optical Properties of Atomic-Scale Heterostructure Based on MXene and MN (M = Al, Ga): A DFT Investigation.

ABSTRACT: After the discovery of graphene, a lot of research has been conducted on two-dimensional (2D) materials. In order to increase the performance of 2D materials and expand their applications, two different layered materials are usually combined by van der Waals (vdW) interactions to form a heterostructure. In this work, based on first-principles calculation, some charming properties of the heterostructure constructed by Hf₂CO₂, AlN and GaN are addressed. The results show that Hf₂CO₂/AlN and Hf₂CO₂/GaN vdW heterostructures can keep their original band structure shape and have strong thermal stability at 300 K. In addition, the Hf₂CO₂/MN heterostructure has I-type band alignment structure, which can be used as a promising light-emitting device material. The charge transfer between the Hf₂CO₂ and AlN (or GaN) monolayers is 0.1513 (or 0.0414) |e|. The potential of Hf₂CO₂/AlN and Hf₂CO₂/GaN vdW heterostructures decreases by 6.445 eV and 3.752 eV, respectively, across the interface. Furthermore, both Hf₂CO₂/AlN and Hf₂CO₂/GaN heterostructures have remarkable optical absorption capacity, which further shows the application prospect of the Hf₂CO₂/MN heterostructure. The study of this work provides theoretical guidance for the design of heterostructures for use as photocatalytic and photovoltaic devices.

SUBMITTER: Ren K

PROVIDER: S-EPMC8467826 | biostudies-literature |

REPOSITORIES: biostudies-literature

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