Predicted spin–valley coupling and valley polarization in two-dimensional MoSi2X4 (X = N, P, and As).

Ferroelectrics is expected to be an alternative to traditional solar cells, because its bulk photovoltaic effect (BPVE) may overcome the Shockley–Queisser limit. Here, we propose that a family of polar materials without centrosymmetry, distorted 1T (1T′′′) transition-metal dichalcogenides, shows a large BPVE in the infrared and visible light due to their moderate band gaps based on density-functional-theory (DFT) calculations. We find that the BPVEs in bulks are much higher than those in monolayers because of the smaller band gaps and more delocalized valence band states. We further show that strain engineering serves as an efficient strategy to enhance the BPVE of 1T′′′-MoS2 bulk. The shift-current responses in the bulks spotlight their potential for applications into solar energy harvesting. This work provides the theoretical evidence of BPVE in 1T′′′ transition-metal dichalcogenides and guidance on the design of novel materials with an enhanced BPVE for green-energy technologies.

Two-dimensional (2D) materials have attracted increasing interest in the past decades due to their unique physical and chemical properties for diverse applications. In this work, we present a first-principle design...

Searching for two-dimensional (2D) materials with high phase-transition temperature and magnetic anisotropy is critical to the development of spintronics. Herein, we investigate the electronic and magnetic properties of 2D TiX3...