Effect of transition metal doping on the photoelectric and magnetic properties of monolayer PtSe₂: a first-principles analysis

Abstract This study investigates the effects of transition metal X (X = V, Cr, Mn, Fe, Co, Ni, Nb, Mo, Ta, W, and Re) doping on the geometric structure, electronic structure, magnetic properties, and optical properties of single-layer PtSe 2 materials using first-principles calculations. The results indicate that intrinsic PtSe 2 is a non-magnetic semiconductor, while all other doped systems exhibit magnetic properties, except for those doped with Co and Ni. Among these, the doped systems containing Mo, Cr, Fe, and V all exhibit semimetallic characteristics. Calculations of the Integrated Spin Density and its magnitude for the doped PtSe 2 systems reveal that doped systems such as V, Cr, and Mo exhibit significant local spin polarization, manifested as large differences in spin density; whereas systems such as Ta, W, and Re show smaller spin density differences, indicating higher consistency in magnetic moment direction and stable magnetic order. Differential charge density analysis shows that in systems doped with V, Cr, Mn, and Mo, distinct electron aggregation regions form around the doped atoms, while adjacent Se atom regions exhibit electron dissipation. In Co and Ni-doped systems, electron rearrangement is weaker, and the overall charge distribution is close to the intrinsic structure. In terms of optical properties, the static dielectric constant, reflectance, and absorption coefficient of most doped systems are enhanced compared to intrinsic PtSe 2 , with some systems exhibiting blue shift or red shift phenomena, indicating that doping regulation can effectively expand their response range in optoelectronic devices. These results provide a theoretical basis for designing two-dimensional materials with tunable magnetic and optical properties, demonstrating the application potential of PtSe 2 -based doped systems in spintronics, photodetection, and gas sensing.