Electronic structure and conductivity in functionalized multilayer black phosphorene

Phosphorene and its components are highly reactive to oxygen when exposed to\nambient conditions due to the presence of lone pairs of electrons on phosphorus\natoms. Functionalization serves as a solution to prevent the chemical\ndegradation of these materials. In this paper, we investigate the impact of\nrelatively strong covalent or noncovalent functionalization on phosphorene\n(monolayer black phosphorus (BP)), few-layer BP, and bulk BP. We use an\neffective tight-binding Hamiltonian that corresponds to one orbital per site,\nwherein covalent functionalization is simulated by atomic vacancies, and\nnoncovalent functionalization is simulated by Anderson disorder. We demonstrate\nthat these two types of functionalization act differently on the electronic\nstructure and quantum diffusion, particularly affecting the gap and mobility\ncharacteristics, especially with a high degree of functionalization. However,\nwe also show that the mobility gap is not significantly modified by the two\ntypes of defect. We also analyze the electron-hole asymmetry that is more\nimportant for multilayer and bulk BP.\n