Theoretical design of a photodetector based on a two-dimensional SnSe2/GaP type-II heterostructure. Issue 15 (28th March 2023)

• Record Type: Journal Article
• Authors: Wang, Jiaxin; Wei, Xing; Xuan, Jinzhe; Zhang, Yan; Fan, Jibin; Ni, Lei; Yang, Yun; Liu, Jian; Tian, Ye; Ma, Shu; Duan, Li
• Is Part Of: CrystEngComm. Volume 25:Issue 15(2023)
• Page Start: 2326
• Page End: 2338
• Publication Date: 2023-03-28
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/d2ce01704k
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : The effect on the band alignment of SnSe2 /GaP heterojunctions was investigated by applying an external electric field and strain perpendicular to the interface between two monolayers of SnSe2 and GaP. Abstract : The low-dimensional structure and excellent optical properties of two-dimensional (2D) materials have made them a hot theme for research in materials science. In this study, the geometrical properties, electrical properties, and optical characteristics of a new SnSe2 /GaP heterostructure are explored using first principles. We also calculated the effect of different rotational angle stacking and doping on the optoelectronic properties of the SnSe2 /GaP heterostructure. The results show that the SnSe2 /GaP heterostructure is a type-II heterostructure with an indirect bandgap of 0.439 eV, and the photogenerated electron–hole pairs can be effectively separated at the heterogeneous interface. The heterostructure bandgap can be adjusted to zero by modulating the interlayer distance or by applying electric fields and strains, enabling semiconductor–metal leapfrogging. It is noteworthy that when imposing an electric field of 0.4 V Å −1, the SnSe2 /GaP heterostructure varies from type-II heterostructure into type-I. In particular, unlike the two monolayers, the formation of the SnSe2 /GaP heterostructure results in a significant increase in absorbance, especially in the UV absorption region, and has a wider light absorption range. This shows that SnSe2 /GaP heterostructure has great potential for future multifunctional optoelectronic devices.