Superior spin-polarized electronic structure in MoS2/MnO2 heterostructures with an efficient hole injection. Issue 20 (14th May 2019)

• Record Type: Journal Article
• Authors: Zhou, Baozeng; Li, Zheng; Wang, Jiaming; Wang, Kangqiang
• Is Part Of: Physical chemistry chemical physics. Volume 21:Issue 20(2019)
• Page Start: 10706
• Page End: 10715
• Publication Date: 2019-05-14
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp01146c
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Different functional applications of MoS2 /MnO2 ferromagnetic van der Waals heterostructures are realized by stacking model engineering and external field regulation. Abstract : Two-dimensional (2D) materials with intrinsic magnetism and low hole injection barriers to transition metal dichalcogenides are crucial to develop dopant-free all-2D p-type spin field effect transistors for CMOS logic and spintronic applications. Here, the electronic structures of 2D MoS2 /MnO2 heterostructures are investigated by first-principles calculations, where the monolayered MnO2 has two polymorphs including magnetic metal h-MnO2 and magnetic semiconductor t-MnO2 . Both the MoS2 /h-MnO2 and MoS2 /t-MnO2 heterostructures show p-type doping for MoS2 . In the MoS2 /h-MnO2 model with a semiconductor/metal contact, the charge transfer can affect the occupation of Mn 3d and O 2p orbitals, which results in a half-metallic characteristic of the heterostructure with a Schottky barrier height of only 0.15 eV. However, the MoS2 /t-MnO2 model with a semiconductor/semiconductor contact shows a spin-gapless electronic structure. Moreover, the type-II band alignment of the MoS2 /t-MnO2 heterostructure can facilitate the effective separation of electrons and holes, which can enhance the lifetime of interlayer excitons. The long interlayer exciton lifetime makes it a good candidate for electron–hole separators and related optoelectronic devices. By applying vertical compression, the spin channel of the half-metallic MoS2 /h-MnO2 heterostructure can be reversed and the spin-gapless band structure of the MoS2 /t-MnO2 heterostructure becomes half-metallic. Furthermore, by applying a gate voltage, the Schottky barrier height and the spin-gapless gap can be tailored. The tunable spin polarization, spin-polarized direction and exciton recombination rate provide a feasible way toward spintronics and optoelectronics.