Effects of Graphene/BN Encapsulation, Surface Functionalization and Molecular Adsorption on the Electronic Properties of Layered InSe: A First-Principles Study

Abstract

By using first-principles calculations, we investigated the effects of graphene/boron nitride (BN) encapsulation, surface functionalization by metallic elements (K, Al, Mg and typical transition metals) and molecules (tetracyanoquinodimethane (TCNQ) and tetracyanoethylene (TCNE)) on the electronic properties of layered indium selenide (InSe). It was found that an opposite trend of charge transfer is possible for graphene (donor) and BN (acceptor), which is dramatically different from phosphorene where both graphene and BN play the same role (donor). For InSe/BN heterostructure, a change of the interlayer distance due to an out-of-plane compression can effectively modulate the band gap. Strong acceptor abilities to InSe were found for the TCNE and TCNQ molecules. For K, Al and Mg-doped monolayer InSe, the charge transfer from K and Al atoms to the InSe surface was observed, causing an n-type conduction of InSe, while p-type conduction of InSe observed in case of the Mg-doping. The atomically thin structure of InSe enables the possible observation and utilization of the dopant-induced vertical electric field across the interface. A proper adoption of the n- or p-type dopants allows for the modulation of the work function, the Fermi level pinning, the band bending, and the photo-adsorbing efficiency near the InSe surface/interface. Investigation on the adsorption of transition metal atoms on InSe showed that Ti-, V-, Cr-, Mn-, Co-adsorbed InSe are spin-polarized, while Ni-, Cu-, Pd-, Ag- and Au-adsorbed InSe are non-spin-polarized. Our results shed lights on the possible ways to protect InSe structure and modulate its electronic properties for nanoelectronics and electrochemical device applications.

References in corpus (8)

• High Electron Mobility, Quantum Hall Effect and Anomalous Optical Response in Atomically Thin InSe
• Observation of tunable bandgap and anisotropic Dirac semimetal state in black phosphorus
• Low-Resistance 2D/2D Ohmic Contacts: A Universal Approach to High-Performance WSe2, MoS2, and MoSe2 Transistors
• The Electronic Properties of Phosphorene/Graphene and Phosphorene/Hexagonal Boron Nitride Heterostructures
• Tuning the Band Gap in Silicene by Oxidation
• Charge Transfer and Functionalization of Monolayer InSe by Physisorption of Small Molecules for Gas Sensing
• Large Electronic Anisotropy and Enhanced Chemical Activity of Highly Rippled Phosphorene
• Defects and oxidation resilience in $InSe$

Cited by in corpus (1)

• Fermi level depinning via insertion of a graphene buffer layer at the gold-2D tin monoxide contact