Two-dimensional C6X (X = P2, N2, NP) with ultra-wide bandgap and high carrier mobility

Abstract Two-dimensional (2D) materials with ultra-wide bandgap and high carrier mobility are highly promising for electronic applications. We predicted 2D C 3 P, C 3 N and C 6 NP monolayers through density-functional-theory calculations. The phonon spectra and Ab initio molecular dynamics simulation confirm that the three 2D materials exhibit good phase stability. The C 3 P monolayer shows excellent mechanical flexibility with a critical strain of 27%. The C 3 P and C 6 NP monolayers are ultra-wide bandgap semiconductors based on Heyd-Scuseria-Ernzerhof hybrid functional (HSE06) calculation. The C 3 P monolayer has a direct bandgap of 4.42 eV, and the C 6 NP and C 3 N monolayer have indirect bandgaps of 3.94 and 3.35 eV, respectively. The C 3 P monolayer exhibits a high hole mobility of 9.06 × 10 4 cm 2 V −1 s −1 , and the C 3 N monolayer shows a high electron mobility of 4.52 × 10 4 cm 2 V −1 s −1 . Hence, the C 3 P, C 3 N, and C 6 NP monolayers are promising materials for various electronic devices.