Effect of non-metallic doping on the electronic structure of GaS monolayers and mercury adsorption performance

This study systematically explores the optical properties of non-metallic doped single-layer GaS materials and their performance in mercury adsorption. Using first-principles calculations, the effects of different doping elements (including C, N, O, Si.) on the optical properties of GaS were investigated, with a focus on the regulatory effects of doping on the material's dielectric function, absorbance, reflectivity, and energy loss function. The results demonstrate that the doping elements induce substantial changes in the electronic structure and optical response of GaS. Notably, the Ga-doped Si system displays pronounced polarization response and light absorption capability in the low-energy region, resulting in a shift towards longer wavelengths in its absorption spectrum. The reflectivity of different doping systems in the low-energy and high-energy regions also exhibits divergent trends. Doping with elements such as Si and C shifts the absorption peak to lower energies, narrows the band gap, and enhances the material's absorption of low-energy light. In addition, energy loss function analysis elucidates the contribution of doped elements to the stability of the electronic structure in the low-energy region. The Ga-site doped N and S-site doped O systems demonstrate exceptional electronic stability. In conclusion, the findings of this study demonstrate that doping regulates the optical and electronic properties of GaS materials, thus providing novel optimisation strategies for applications such as optoelectronic devices, solar cells, and sensors. Through in-depth analysis of this study, we provide a theoretical basis for designing efficient optoelectronic materials and lay the foundation for applied research in related fields.