In recent years a new class of 2D materials with pentagonal structure is drawing considerable attention due to their novel chemical and physical properties . The study of pentagonal 2D structures, similar to the Cairo pentagonal tiles, began when penta-graphene (PG), a fivemembered rings of carbon atoms, was theoretically characterized . The novel mechanical and electronic properties, and broad applications of penta-graphene inspired to explore more isostructures. Since then, tremendous efforts have been made to study the corresponding families of 2D materials both theoretically and experimentally. For example, penta-silicene nanoribbons , penta PdSe 2 are successfully fabricated by micromechanical exfoliation technique . In addition, penta-germanium , penta-arsenic carbide , penta-CN 2 , penta-B 2 C have been studied theoretically to investigate different physical and chemical properties. Interestingly, several studies show that penta-2D monolayer exhibits excellent chemical and physical properties, some of them are even better than hexagonal monolayer counterparts due to their unique puckered geometry. For example, penta-CN 2 exhibits higher energy density and greater in-plane stiffness than the h-BN monolayer .