Electronic and optical properties of Janus ZrSSe by density functional theory

Abstract

In the present work, we investigate systematically the electronic and optical properties of Janus ZrSSe using first-principles calculations. Our calculations demonstrate that the Janus ZrSSe monolayer is an indirect semiconductor at equilibrium. The band gap of the Janus ZrSSe is 1.341 eV using the Heyd-Scuseria-Ernzerhof hybrid functional, larger than the band gap of ZrSe 2 monolayer and smaller than that of ZrS 2 monolayer. Based on the analysis of the band edge alignment, we confirm that the Janus ZrSSe monolayer possesses photocatalytic activities that can be used in water splitting applications.While strain engineering plays an important role in modulating the electronic properties and optical characteristics of the Janus ZrSSe monolayer, the influence of the external electric field on these properties is negligible. The biaxial strain, 3 b , has significantly changed the band of the Janus ZrSSe monolayer, and particularly, the semiconductor-metal phase transition which occurred at 3 b ¼ 7%. The Janus ZrSSe monolayer can absorb light in both visible and ultraviolet regions. Also, the biaxial strain has shifted the first optical gap of the Janus ZrSSe monolayer. Our findings provide additional information for the prospect of applying the Janus ZrSSe monolayer in nanoelectronic devices, especially in water splitting technology.

Phonons and excitons in ZrSe2–ZrS2 alloys

“…An interesting observation is that the convex hull shows that there is, in principle, a stable ZrSSe phase (x = 1) with Janus distribution. 40,41 However, the energy gain is so small that this is unlikely to show up in our samples. In Fig.…”

Effects of electric field and strain engineering on the electronic properties, band alignment and enhanced optical properties of ZnO/Janus ZrSSe heterostructures

“…For the ZrSSe monolayer, we previously demonstrated that the SOC effects tend to cause the appearance of band splitting in the valence band of ZrSSe monolayer, leading to its band gap reduction. 38 However, it should be noted that although the SOC effects give rise to a splitting of the bands and reduce the band gap value of the ZnSSe monolayer, it hardly changes the shape of the bands. 54 Therefore, the SOC effects are not considered in the following calculations because they have little signicant change in the band dispersion of the ZnO/ZrSSe heterostructure.…”

“…To date, several Janus materials have been developed, such as Janus PtSSe, 34,35 SnSSe 36 and ZrSSe 37,38 monolayers. Guo et al, 37 via rst-principle calculations demonstrated that the Janus ZrSSe monolayer is dynamically and mechanically stable.…”

“…Guo et al, 37 via rst-principle calculations demonstrated that the Janus ZrSSe monolayer is dynamically and mechanically stable. Vu et al 38 showed that the Janus ZrSSe monolayers exhibit photocatalytic activity, which is suitable for water splitting applications.…”

Spin–orbit coupling effect on electronic, optical, and thermoelectric properties of Janus Ga2SSe

“…12 Also, one can modulate the electronic properties of Janus monolayers by an applied strain 13 or external electric eld. 14 Recent DFT calculations demonstrated that MoSeTe possesses high absorption intensity and becoming a great candidate for applications in optoelectronic devices. 15 Recently, van der Waals heterostructures based Janus monolayers have been studied with a lot of attention.…”