Photoelectric properties of Pb ions adsorbed on black phosphorene in water

Using density functional theory, the effects of Pb2+ coverage and Fe modification on the electronic properties of black phosphorus in water were calculated. The investigation found that the increasing of Pb2+ coverage improves the stability of the structure and the adsorption height, and makes the bond length of the P-P bond continuously increase, and the modification of Fe further increases the adsorption height of the system. Black phosphorene has a direct bandgap semiconductor structure in water, with a bandgap value of 0.759eV, and the adsorption of Pb2+ makes it a metal structure, and the modification of Fe makes the bandgap reopened and becomes a direct bandgap semiconductor structure. Intrinsic black phosphorus has strong sp orbital hybridization, s orbital and p orbital make great contributions to the conduction band and valence band, the adsorption of Pb2+ makes the total density of states increase, and the value of the density of states at the Fermi level increases, the density of states crosses the Fermi level, and the system exhibits metallicity. It can be seen that the adsorption of Pb ions and the modification of Fe have changed the structural properties of the black phosphene system in aqueous solution, and the structural stability of the system has been continuously improved, which has important guiding significance for removing Pb ions in water, purifying water quality, protecting ecological environment and human life and health.