Electronic structures of multilayer two-dimensional silicon carbide with oriented misalignment

Abstract

The direct bandgap is favored for optoelectronic applications, such as light emitting or laser diodes and solar cells. While monolayer two-dimensional graphene-like silicon carbide (2d-SiC) possesses a moderate direct bandgap, multilayer 2d-SiC was recently found to exhibit an indirect bandgap. In this paper, our ab initio electronic study demonstrates that a controllable direct bandgap of bilayer/trilayer 2d-SiC can be realized via the interlayer oriented misalignment, where their direct-bandgap character can be maintained for most rotation angles. This misalignment-induced direct bandgap shows a decreasing tendency with a larger commensuration cell, where the minimum direct optical transition frequency can vary from infrared to visible. Our work implies that the interlayer oriented misalignment is a crucial way to tailor electronic structures of multilayer 2d-SiC, facilitating potential applications for optoelectronic devices. 8 such as graphene or silicone with mediate bandgaps (i.e. 1.0-2.0 eV) that are highly desired by the field effect transistor and the solar cell [8,35] are still difficult to achieve. Therefore, our revealed mediate direct bandgap within the range of 1.2-2.1 eV obtained via the interlayer oriented misalignment shall be of scientific importance and desired by the industry. SummaryTo conclude, we explore the consequence of the interlayer rotation misalignment on the electronic structures of multilayer 2d-SiC. A novel physical phenomenon is revealed where the oriented misalignment can induce an indirect-to-direct bandgap transition for multilayer 2d-SiC. This induced direct bandgap, which decreases with a larger commensuration cell, is maintained for most rotation angles and controllable within the range of 1.2-2.1 eV through artificially tailoring the rotation angle between neighboring layers. Our results indicates that the oriented misalignment provides an efficient way to artificially tailor desirable electronic properties of multilayer 2d-SiC, which would favor their future optoelectronic applications such as light emitting diode, field effect transistor, and solar cells.The direct bandgap is favored for optoelectronic applications, such as light emitting or laser diodes and solar cells. While monolayer two-dimensional graphene-like silicon carbide (2d-SiC) possesses a moderate direct bandgap, multilayer 2d-SiC was recently found to exhibit an indirect bandgap. In this paper, our ab initio electronic study demonstrates that a controllable direct bandgap of bilayer/trilayer 2d-SiC can be realized via the interlayer oriented misalignment, where their direct-bandgap character can be maintained for most rotation angles. This misalignment-induced direct bandgap shows a decreasing tendency with a larger commensuration cell, where the minimum direct optical transition frequency can vary from infrared to visible. Our work implies that the interlayer oriented misalignment is a crucial way to tailor electronic structures of multilayer 2d-SiC, facilitating potential applications for optoelectronic ...

Two‐dimensional Silicon‐Carbon Compounds: Structure Prediction and Band Structures

“…For example, it was proposed that electronic and magnetic properties can be tuned through fluorination [21] and that the bandgap can be switched from indirect to direct in multilayer SiC through rotational mismatch of the layers. [22] Further studies discuss their optoelectronic properties, [11,23,24] their catalytic activity for CO oxidation [25] or oxygen reduction, [26] and their use as gas sensors. [27] Also their mechanical stability was addressed and found to depend greatly on Si/C composition and local Si concentration.…”

“…A wealth of theoretical studies has subsequently been published reporting various properties of 2D Si x C y sheets. For example, it was proposed that electronic and magnetic properties can be tuned through fluorination and that the bandgap can be switched from indirect to direct in multilayer SiC through rotational mismatch of the layers . Further studies discuss their optoelectronic properties,, , their catalytic activity for CO oxidation or oxygen reduction, and their use as gas sensors .…”

Performance of SCAN Meta-GGA Functionals on Nonlinear Mechanics of Graphene-Like g-SiC

“…g-SiC mono-layers have not been fabricated yet: only a few layers 2D-SiC films have so far been fabricated through solution-based exfoliation [5]. Extensive theoretical studies have been done on the structural stability, thermodynamic stability, electronic, catalytic, and optical properties of g-SiC [3,[6][7][8][9][10][11][12][13][14][15][16][17][18].…”

Liquid–Liquid Phase Transition in Nanoconfined Silicon Carbide

“…Silicon carbide is one of the most promising materials for power electronics, hard materials, and biomaterials, due to its superior properties. 40 Specifically, 2D-SiC is reported to have a moderate direct band gap 41,42 and exhibits improved photoluminescence capability. 43 Confining liquid in quasi-one or two dimensions is believed to lead to the discovery of new and controversial phenomena in experiments and simulations 44−46 and is also a powerful way of synthesizing nanomaterials in a controlled manner.…”