Anisotropic PC₆N Monolayer with Wide Band Gap and Ultrahigh Carrier Mobility

Abstract

The discovery of two-dimensional (2D) materials with direction-control behavior, wide band gap, and high carrier mobility is highly desirable for the development of advanced optoelectronic devices with photoresponse in the blue and ultraviolet range. Here, we predict an ideal optoelectronic material, a buckled graphene-like PC 6 N, which not only shows a direct wide band gap of 2.56 eV and anisotropic high hole mobility (10 4 cm 2 V −1 s −1 ) but is also transparent to visible light and has a high absorption coefficient (10 5 cm −1 ) in the ultraviolet region. In this way, PC 6 N presents both a wide band gap and high mobility, a long-pursued target in the 2D semiconducting field. Lone electron pairs, originated from N and P atoms, disconnect delocalized π electrons of C 6 rings, making the material a semiconductor. Its anisotropic charge transport can be attributed to the direction-dependent atomic arrangement. PC 6 N shows a high melting point, good dynamical stability, and oxidation resistance to air. These interesting properties make the PC 6 N monolayer a promising candidate for application in novel electronic devices.

Wide Band Gap P3S Monolayer with Anisotropic and Ultrahigh Carrier Mobility

“…The anisotropy of 2D materials provides another degree of freedom to adjust their electronic, mechanical, and optical properties with an opportunity for the development of direction-dependent electronic devices. Until now, anisotropic 2D materials have been successfully applied to some novel optoelectronic devices (e.g., integrated digital inverters, polarization-sensitive photodetectors, and crystal orientation induced diodes), exhibiting intriguing properties and unique applications.…”

“…On the other hand, for 2D covalent compounds, increasing the polarity of the covalent bond generally results in an enhancement of the band gap, which can be achieved by increasing the electronegativity differences between the constituent atoms, such as in CN 2 and PC 6 N . It is well-known that sulfur (S) shows a larger electronegativity than P. S atoms also have the ability to form 2D materials with other nonmetallic elements (e.g., B, C, N, and Si), − exhibiting a high structural stability and interesting properties.…”

BC6P Monolayer: Isostructural and Isoelectronic Analogues of Graphene with Desirable Properties for K-Ion Batteries

“…After extensive structure search, we find two hitherto unknown graphenelike monolayers, BC 2 P (with the space group P 2 1 and 2 formula units, Figure a,b) and BC 6 P (with the space group Pm and 1 formula unit, Figure e,f). A striking feature is the fully planar structure, in sharp contrast to the P-based 2D materials PC, PC 6 , PN, BP 3 , and PC 6 N . The planar structure facilitates not only fast ion transport but also experimental synthesis due to compatibility with the available substrates. − …”

RuN2 Monolayer: A Highly Efficient Electrocatalyst for Oxygen Reduction Reaction

“…The atomic structure of the 2D RuN 2 monolayer was predicted using the particle swarm optimization (PSO) method within the crystal structure analysis by particle swarm optimization (CALYPSO) code, which has been widely employed to search for novel 2D materials with good durability and interesting properties. − Furthermore, the spin-polarized density functional theory (DFT) calculations using Vienna Ab initio Simulation Package (VASP) , were carried out to obtain the stable configuration and the related energies as well as properties. We employed the projector-augmented plane wave (PAW) , method to treat the ion–electron interaction.…”