Strain-Tunable Electronic Properties and Band Alignments in GaTe/C2N Heterostructure: a First-Principles Calculation

Abstract

Recently, GaTe and C2N monolayers have been successfully synthesized and show fascinating electronic and optical properties. Such hybrid of GaTe with C2N may induce new novel physical properties. In this work, we perform ab initio simulations on the structural, electronic, and optical properties of the GaTe/C2N van der Waals (vdW) heterostructure. Our calculations show that the GaTe/C2N vdW heterostructure is an indirect-gap semiconductor with type-II band alignment, facilitating an effective separation of photogenerated carriers. Intriguingly, it also presents enhanced visible-UV light absorption compared to its components and can be tailored to be a good photocatalyst for water splitting at certain pH by applying vertical strains. Further, we explore specifically the adsorption and decomposition of water molecules on the surface of C2N layer in the heterostructure and the subsequent formation of hydrogen, which reveals the mechanism of photocatalytic hydrogen production on the 2D GaTe/C2N heterostructure. Moreover, it is found that in-plane biaxial strains can induce indirect-direct-indirect, semiconductor-metal, and type II to type I or type III transitions. These interesting results make the GaTe/C2N vdW heterostructure a promising candidate for applications in next generation of multifunctional optoelectronic devices.Electronic supplementary materialThe online version of this article (10.1186/s11671-018-2708-x) contains supplementary material, which is available to authorized users.

Tuning the electronic, optical and structural properties of GaS/C2N van der Waals heterostructure for photovoltaic application: first-principle calculations

“…In a photovoltaic cell, electron-hole pairs are separated when visible light irradiates on the semiconductor surface, where electrons (e − ) will be promoted to the n-type and holes (e + ) will be on the p-type [40]. However, there is still high rapid recombination of charge carriers in C 2 N. Lately, vdWs heterostructure has been an efficient way of adjusting the properties of 2D materials, such as band structure tuning and charge carrier separation [41]. Type-I (symmetric), type II (staggered) and type III (broken) band alignments in vdW heterostructures have their own specific applications to allow various device varieties [42][43][44][45].…”

Recent Advances on Tuning the Interlayer Coupling and Properties in van der Waals Heterostructures

“…Li et al. [ 228 ] explored the strain‐tunable band alignments of GaTe/C 2 N heterostructure. Guo et al.…”

“…The applied external field could trigger the semiconductor-to-metal transition, which is meaningful for optoelectronic nanodevices. Li et al [228] explored the strain-tunable band alignments of GaTe/C 2 N heterostructure. Guo et al [229] studied the regulation of electronic and optical properties of MoSS 2 /InS 2 vdW heterostructure by biaxial strain.…”

Tuning Electronic Properties of GaSe/Silicane Van der Waals Heterostructure by External Electric Field and Strain: A First-Principle Study

“…Strain is known to also affect the electronic structures of the vdW heterostructure [38,[63][64][65][66][67][68]. Here, we studied the effect of inplane biaxial strain on the electronic structures of the GaSe/SiH vdW heterostructure.…”