Tunable electronic properties and optoelectronic characteristics of MoGe₂N₄/SiC van der Waals heterostructure

Abstract

The assembly of van der Waals (vdw) heterostructure with easily regulated electronic properties provides a new way for the expansion of two-dimentional (2D) materials and promotes the development of optoelectronics, sensors, switching devices and other fields. In this work, a systematic investigation of the electronic properties of MoGe2N4/SiC heterostructures using density functional theory (DFT) has been conducted, along with the modulation of electronic properties by vertical strain and the potential application prospects in optoelectronic devices. The results show that MoGe2N4/SiC heterostructure has excellent dynamic and thermal stability and belongs to type-II band alignment semiconductors. This is extremely beneficial for the separation of photo-generating electron-hole pairs, so it has important significance for the development of photovoltaic materials. In addition, under the control of vertical strain, the semiconductor-metal transition occurs in the MoGe2N4/SiC heterostructure when the compressive strain reaches 6%. In the case of compressive strain less than 6% and tensile strain, the MoGe2N4/SiC heterostructure maintains the type-II band alignment semiconductor characteristics. Meanwhile, we find that the MoGe2N4/SiC heterostructure has optical absorption coefficients of up to 105 in the visible and ultraviolet light ranges, which can improve the absorption coefficients of the MoGe2N4 and SiC monolayer in some visible light regions. Finally, the optical conductivity of the MoGe2N4/SiC heterostructure exhibits significant anisotropy, with the armchair direction displaying higher conductivity within the orange light range. In conclusion, the formation of vdW heterostructure by vertically stacking MoGe2N4 and SiC monolayers can effectively improve their electronic and optical properties, which provides a valuable reference for the future development of electronic devices and photovoltaic materials.

Theoretical prediction of the electronic structure, optical properties and contact characteristics of a type-I MoS2/MoGe2N4 heterostructure towards optoelectronic devices

“…The combination of MoGe 2 N 4 and other 2D materials has also been investigated extensively to uncover novel phenomena, giving rise to the development of vdW-based heterostructures towards multifunctional applications. Many heterostructures combining MoGe 2 N 4 with other 2D materials have been proposed and discovered, such as BP/MoGe 2 N 4 , 38 graphene/MoGe 2 N 4 , 39 SiC/MoGe 2 N 4 40 and so forth. 41 For instance, Nguyen et al 38 constructed the BP/MoGe 2 N 4 heterostructure and predicted that its formation would lead to an enhancement in the material's absorption coefficient in both the visible and ultraviolet light regions.…”

“…41 For instance, Nguyen et al 38 constructed the BP/MoGe 2 N 4 heterostructure and predicted that its formation would lead to an enhancement in the material's absorption coefficient in both the visible and ultraviolet light regions. Yang et al 40 demonstrated that the combination in the SiC/MoGe 2 N 4 heterostructure effectively enhances the electronic and optical properties of the constituent SiC and MoGe 2 N 4 monolayers. All these findings suggest that an MoGe 2 N 4 monolayer can be considered as a promising material for the design of novel heterostructures, characterized by structural stability and the emergence of novel phenomena.…”