Is the Metallic Phosphorus Carbide (β₀-PC) Monolayer Stable? An Answer from a Theoretical Perspective

Phosphorus carbide (PC) has been the subject of major research efforts in recent years. In this regard, very recently, a stoichiometric metallic phosphorus carbide (β 0 -PC) monolayer has been proposed as locally stable with one lone nonbonding electron in each C atom. Therefore, the ambiguity of coexistence of a nonbonding electron with metallic properties for β 0 -PC is reported and hence deserves further explanation. Herein, using first-principles calculations, we have explored the stability and electronic properties of β 0 -PC to resolve this ambiguity. The metallic behavior of β 0 -PC is explained on the basis of electron delocalization involving P and C atoms along a zigzag chain of β 0 -PC. We have also explored the possibility of getting a β 0 -PC monolayer via homogeneous doping of C (P) into phosphorene (graphene) and layer exfoliation of 3D bulk PC with β-InS-like structure, which has been experimentally synthesized.