Optical performances of (\({\varvec{A}}{\varvec{u}},{\varvec{S}}{\varvec{n}},{\varvec{I}}\)) adsorbed phosphorene nanostructures with improved absorption in visible region: a comparative computational study

Phosphorene is a remarkable 2D material with huge potential in photonics and optoelectronic. The influence of adsorption of \(Au, \; Sn \; \text{and} \; I\) atoms on the optical performance of phosphorene monolayer by the computational simulation based on density functional theory has been investigated. All of the nanostructures have a direct bandgap \((0.32\; \text{to} \;0.79\; {\text{eV}})\) are semiconducting in nature, allowing the development of wide range of optical semiconductor devices. The findings demonstrate that in pure phosphorene monolayer, absorption peak occurs primarily in the blue region of visible spectrum and in certain portion of ultraviolet region of spectrum. The absorption peaks move towards the red region of the visible light spectrum after the adsorption of \(Au, \; Sn \; \text{and} \; I\) metal atoms on the pristine phosphorene surface. Among them, \(Sn\) adsorbed nanostructures exhibit significantly high and stable absorption spread across the entire visible range (400–780 nm). The dielectric functions and refractive index of all nanostructures also computed. Since \(Au, \; Sn \; \text{and} \; I\) adsorbed phosphorene semiconductor nanostructures exhibit enhanced absorption in the broad usable range of visible spectrum make them the ideal choice for photonic and optoelectronic applications.