Regulation of the properties of monolayer β-Ga ₂ O ₃ through N and P doping and adsorption

In this study, the modulation of the optoelectronic properties of monolayer [Formula: see text]-Ga 2 O 3 through the adsorption and doping of N and P atoms was systematically investigated using density functional theory. The calculated bandgap of pristine [Formula: see text]-Ga 2 O 3 is 4.788[Formula: see text]eV. All adsorption and doping systems exhibit reduced bandgaps, with N-doping inducing the most significant reduction to 4.179[Formula: see text]eV. Notably, P-adsorption and P-doping introduce donor levels near the conduction band, shifting the Fermi level into the conduction band and conferring n-type conductivity. In contrast, N-modification facilitates a decrease in electron effective mass, promoting electron-hole separation. Optically, the static dielectric constant increases markedly to 2.64 in the P-adsorption system, enhancing charge confinement. Furthermore, the optical absorption extends into the visible region, with the P- doped system achieving a maximum absorption coefficient of 68,881.18[Formula: see text]cm[Formula: see text] in the UV range. The static refractive index is also enhanced, reaching 1.63 for P-adsorption. Additionally, the conductivity peaks for N-adsorbed and P-doped systems rise to 1.04 and 1.10, respectively, indicating enhanced photon absorption and energy storage capabilities. These findings provide quantitative insights and a theoretical foundation for designing [Formula: see text]-Ga 2 O 3 -based optoelectronic devices, such as solar cells and UV photodetectors.