A new two-dimensional (2D) layered material, namely, titanium trisulfide (TiS3) monolayer, is predicted to possess novel electronic properties. Ab initio calculations show that the perfect TiS3 monolayer is a direct-gap semiconductor with a bandgap of 1.02 eV, close to that of bulk silicon, and with high carrier mobility. More remarkably, the in-plane electron mobility of the 2D TiS3 is highly anisotropic, amounting to about 10 000 cm2 V-1 s-1 in the b direction, which is higher than that of the MoS2 monolayer, whereas the hole mobility is about two orders of magnitude lower. Furthermore, TiS3 possesses lower cleavage energy than graphite, suggesting easy exfoliation for TiS3. Both dynamical and thermal stability of the TiS3 monolayer is examined by phonon-spectrum calculation and Born-Oppenheimer molecular dynamics simulation. The desired electronic properties render the TiS3 monolayer a promising 2D atomic-layer material for applications in future nanoelectronics. New semiconductor: A titanium trisulfide monolayer is predicted to be a direct-gap semiconductor with ultrahigh electron mobility (≈104 cm2 V-1 s-1), which is higher than that of MoS2 and phosphorene. The monolayer can be exfoliated from its bulk phase due to the lower exfoliation energy compared to graphite.
- carrier mobility
- density functional calculations
- direct bandgap
- titanium trisulfide
ASJC Scopus subject areas