Revealing the electronic properties of 2D inorganic biphenylene via atomic doping: Insights from first-principles calculations

Abstract

2D biphenylene has attracted much attention for its unique structure and remarkable properties, with potential uses in various fields. This paper utilizes first-principles calculations to explore the intrinsic properties of 2D inorganic biphenylene (I-BPN) and assess the impact of atomic doping on its electronic properties, with a focus on structure, thermodynamic stability, band structures, density of states, and differential charge density. Results indicate that I-BPN exhibits inherently exceptional structural and thermodynamic stability. Notably, single-atom substitutional doping with Li, C, O, Al, and S elements results in stable structures, all having binding energies below −6.24 eV/atom, and these structures remain stable at 350 K. Al doping maintains the semiconductor characteristics of I-BPN, whereas other dopant elements induce metallic behavior. Double-atom substitutional doping configurations, including Al–C co-doped B, Li–C co-doped B, O–C co-doped N, S–C co-doped N, Al-doped B/C-doped N, Li-doped B/C-doped N, Li-doped B/O-doped N, and O-doped N/S-doped B, exhibit stable structures with binding energies below −5.87 eV/atom and remain stable at 350 K. Specifically, except for the O–C co-doped N structure which exhibits semiconductor characteristics, all other structures display metallic properties. Our findings indicate a potential pathway for experimentally achieving interesting electronic properties in 2D I-BPN for optoelectronic device applications.