Effects of component on the photoelectric properties of two-dimensional van der Waals heterostructure Cs2PbI2(1+x) Cl2(1−x)/Pd2Se3 with Ruddlesen–Popper structure. (24th June 2021)

• Record Type: Journal Article
• Authors: Yan, Meng-Rong; Ding, Yu-Feng; Liu, Biao; Zeng, Ruosheng; Wan, Qiang; Cai, Meng-Qiu
• Is Part Of: Journal of physics. Volume 54:Number 35(2021)
• Publication Date: 2021-06-24
• Subjects: component -- photoelectric properties -- Ruddlesen-Popper structure -- van der Waals heterostructure; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ac08c9
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: Perovskite-based van der Waals heterostructures with high carrier mobility and perfect photoresponse performance can be used to design transistors and photovoltaic devices. However, the function of a single heterojunction is relatively limited because of its specific energy band type. To achieve more controllable device functions, in this work, the band structure, effective mass, optical absorption spectrum, differential charge density and other electronic and optical properties for the novel heterostructure system composed of emerging two-dimensional material Pd2 Se3 with a high electron mobility and all-inorganic halide perovskite Cs2 PbI2(1+ x ) Cl2(1− x ) is systematically studied by using density functional theory. The results demonstrate that the band alignments in Cs2 PbI2 Cl2 /Pd2 Se3 heterostructure realize the transition from type-I to type-II by changing the concentration of I and Cl atoms in the all-inorganic two-dimensional Ruddlesen-Popper perovskite Cs2 PbI2 Cl2, which can be applied to different functional devices. With the increase of iodine atoms, the valence band maximum (VBM) contributed by Pd2 Se3 in the heterostructure moves downward, and the valence band of Cs2 PbI2 Cl2 becomes the new VBM. Moreover, the transport and optical properties for the Cs2 PbI2 Cl2 /Pd2 Se3 heterostructure can be improved, due to the reductions in the band gap and effective mass, which are caused by the transition of band alignment. Our works indicate that a controllable band alignment of Cs2 PbI2 Cl2 /Pd2 Se3 heterostructure can provide theoretical guidance for the flexible designs of devices with multi-functional applications.