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 C3P, C3N and C6NP 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 C3P monolayer shows excellent mechanical flexibility with a critical strain of 27%. The C3P and C6NP monolayers are ultra-wide bandgap semiconductors based on Heyd-Scuseria-Ernzerhof hybrid functional (HSE06) calculation. The C3P monolayer has a direct bandgap of 4.42 eV, and the C6NP and C3N monolayer have indirect bandgaps of 3.94 and 3.35 eV, respectively. The C3P monolayer exhibits a high hole mobility of 9.06 × 104 cm2V−1s−1, and the C3N monolayer shows a high electron mobility of 4.52 × 104 cm2V−1s−1. Hence, the C3P, C3N, and C6NP monolayers are promising materials for various electronic devices.