Anti‐Frosting Perovskite Quantum Dots Films via Femtosecond Laser Composite Texturing

Perovskite quantum dots (QDs), characterized by high photoluminescence quantum yield, narrow half‐peak width, and full‐spectrum tunability, are considered promising candidates for next‐generation light‐emitting displays. However, their poor environmental stability and insufficient frost resistance restrict their application in outdoor displays. Herein, this study proposes an innovative femtosecond laser (Fs‐laser) – based composite texturing strategy. By integrating Fs‐laser technology with calcium chloride solutions, a perovskite QDs film is successfully fabricated that demonstrates both superior luminescent properties and long‐lasting anti‐frosting performance. Through the precise tuning of halogens (Br, Cl, I) and leveraging laser‐induced thermal effects, it achieves perovskite QDs patterns with a full emission spectrum (451–653 nm), fine‐resolution (≈80 µm), narrow emission spectra (≈21 nm, λ = 514 nm), and low excitation energy density (≈14.2 J m −2 ). By embedding CaCl 2 solution into densely arranged micrometer‐scale grooves, the film exhibits frost resistance for up to 60 min. Moreover, the film retains 88% of its initial luminescence intensity after 200 days of immersion in a calcium chloride solution, highlighting its long‐term stability. This strategy provides a novel pathway for developing perovskite‐based luminous devices that are facile to fabricate, capable of full‐color display, and possess long‐term stability and frost resistance.