Arsenic carbide allotropes prediction: An efficient platform for hole-conductions, optical and photocatalysis applications

Based on the first-principle framework and particle swarm optimization approach, we have predicted two allotropes of arsenic carbide (AsC) monolayers consisting of an equimolar mixture of arsenic and carbon atoms with honeycomb structures, namely as puckered and buckled. Besides excellent stability, they present rich properties that could establish an efficient platform for hole-conductions, optical, and photocatalysis applications. The lower cohesive energy, absence of negative frequencies in the phonon dispersion curve, and ab initio molecular dynamics simulation prove both monolayers are thermodynamically, kinetically, and thermally stable at room temperature. Besides, electronic band structure calculations indicate that puckered and buckled configurations of AsC monolayers possess intrinsic band gaps of 1.27 and 1.78 eV. In particular, the absorption coefficient and bandgap of a puckered configuration are significantly tuned under the uniaxial strain and induces a transition from direct to the indirect gap. The appropriate band edge positions and strong absorption coefficient in the broad visible and ultraviolet light region make both monolayers a promising candidate for photocatalytic water-splitting and next-generation optoelectronic devices. The carrier mobility calculation exhibits both monolayers have the largest hole carrier mobility at room temperature, rendering it for a p-type field-effect transistor.