Comparative study of ultraviolet absorption properties between iron selenide nanoparticles and zinc oxide nanoparticles based on first-principles calculations

The intensification of global warming has exacerbated health risks associated with prolonged exposure to high-intensity ultraviolet (UV) radiation. Zinc oxide (ZnO), widely utilized as an inorganic physical sunscreen in commercial products, faces challenges such as significant photodegradation under prolonged UV exposure and limited absorption capacity primarily in the ultraviolet radiation A (UVA) range. These limitations necessitate the development of novel materials with enhanced UV absorption efficiency. In this context, iron selenide (FeSe), known for its metallic nature and broad UV absorption spectrum, emerges as a promising candidate. This study systematically investigates the UV absorption properties of FeSe nanoparticles (NPs) for the first time, comparing them with ZnO NPs through integrated experimental and first-principles theoretical approaches. Results demonstrate that FeSe exhibits superior UV absorption properties compared to ZnO, with a maximum absorption coefficient of 2.5 × 10⁵ cm^-1 at 220 nm. This work not only systematically investigates the UV absorption properties of FeSe for the first time but also establishes a theoretical and experimental foundation for designing stable, high-efficiency UV-absorbing materials.