First-principles study on the electronic structures and optical properties of Ag (111), Ag (111)/AZO (002), and ZnO (002)/Ag (111)

To study the effects of adding Al-doped ZnO (AZO) or ZnO films on Ag layers, this study constructed the atomic structure models of Ag (111), Ag (111)/AZO (002), and ZnO (002)/Ag (111). The electronic structures and optical properties of the three thin film systems were calculated based on density functional theory. To obtain accurate results, the Heyd–Scuseria–Ernzerhof 2006 (HSE06) functional was employed to calculate the dielectric function, extinction coefficient, refractive index, reflectivity, and absorption coefficient for the three systems. The calculated results are in good agreement with the experimental data and other reports. Adding the AZO (002) layer to the Ag (111) layer reduces visible light refraction and enhances infrared reflectivity, whereas adding ZnO (002) increases infrared properties and decreases visible light properties. Both layers improve absorptivity, with AZO (002) providing greater enhancement than ZnO (002). This research demonstrates that the Ag (111), Ag (111)/AZO (002), and ZnO (002)/Ag (111) thin film systems can enhance the thermal insulation and lighting properties of low-emissivity glass and improve its energy-saving effect for buildings.