Electronic and magnetic properties of single-layer boron phosphide associated with materials processing defects

Using density functional theory (DFT), we systemically studied the impact of various point defects on the structural, magnetic and electronic properties of graphene-like boron phosphide (h-BP) monolayer. The results showed that the defect-free monolayer structure retained semiconductor-like the respective bulk compound, but the band gap modifies its character from indirect to direct. The band gaps of h-BP sheet varied from 0.142/0.46 to 0.75/1.26 eV using PBE/HSE06 schemes due to the existence of Stone-Wales (SW) and antisites defects. Also, it should be noted that the defect-free monolayer showed metallic behavior with a noticeable ferromagnetism, by hosting a boron vacancy, and becomes an indirect semiconductor through single (P) and double (P–B) vacancies. Additionally, the stability of the favorable point defects has been predicted based on the cohesive and formation energies. We have collected STM images of the SW defect structure for upcoming experimental observations. This study may be useful when designing novel optoelectronic and magnetic devices that employ defective h-BP monolayers.