Synergistic superconducting and photocatalytic properties in 2D Janus WXY (XY = S, Se)/AlN vdW heterostructures: a DFT study

Abstract The effect of W-Janus (WSSe and WSeS) with AlN monolayers has been investigated by considering their vdW heterostructures (HSs) to study the superconducting and photocatalytic efficiency using Density Functional Theory (DFT). The structural properties show that HS of WXY Janus and AlN monolayer prefer the AA stacking arrangement with binding energies ranging from −0.97 eV to −1.02 eV. The stability of HSs strongly depends upon the atomic configuration arrangement of the relative position of S and Se. Both of these HSs are energetically and thermodynamically stable. Both the HSs possess superconducting transition temperature (T c ) in the range of 20.09 K–22.58 K. The electronic band gap of HSs shows a semiconducting indirect band gap in the range of 2.23 eV–2.27 eV and has type-II band alignment. These HSs have lower carrier effective masses of 0.027–0.086 for m e ∗ and 0.017–0.027 for m h ∗. The optical properties show that absorption coefficients in HSs are higher than their building blocks layer, than individuals having absorption in the visible range of 410 nm, with absorption coefficients of 1.45–1.50 × 105 cm−1. In addition, the position of the conduction band edge and valence band edge in these HSs meets the minimum requirement for the water splitting redox reaction. Therefore, the result indicates that WXY (XY = S, Se)/AlN HSs are potential candidates for superconducting, photocatalytic applications.