First-principles examination of two-dimensional Janus quintuple-layer atomic structures XCrSiN₂ (X = S, Se, and Te)

Abstract

In this work, we propose the novel two-dimensional Janus XCrSiN${_2}$ (X = S, Se and Te) single-layers and comprehensively investigate their crystal structure, electronic properties, carrier mobility by using a...

Novel valleytronic and piezoelectric properties coexisting in Janus MoAZ3H (A = Si, or Ge; Z = N, P, or As) monolayers

“…Substituting the Ge element for the Si element in the MSi 2 N 4 (M = V, Mo, W, Zr, or Hf) ML can form stable Janus MSiGeN 4 MLs, which induces tunable electronic properties, 20 efficient photocatalytic properties, 21,22 Rashba splitting, 23,24 and valley and spin properties. 25–27 The Janus ML XYSiN 2 (X = S, Se, or Te; Y = Mo, or Cr) materials have good stability, high mechanical strength and excellent electronic properties, 28,29 and can be constructed by substituting chalcogen X atoms for the SiN 2 layer on either side of the central Mo atoms in the MoSi 2 N 4 MLs. Forming Janus structures breaks the vertical symmetry of the ML materials and thus causes out-of-plane piezoelectric properties, which is exactly required for energy conversion devices.…”