Strain Engineering: Reduction of Microstrain at the Perovskite Surface via Alkali Metal Chloride Treatment Enhances Stability.

ABSTRACT: Degradation of halide perovskites under a humid atmosphere is the major challenge preventing widespread commercial deployment of this material class. Here it is shown that strain engineering via alkali metal chloride treatment at the FAPbI₃/SnO₂ interface effectively improves moisture-related stability. CsCl and KCl treatments reduce microstrain at the perovskite surface and slow the α- to δ-phase transformation. Alkali metal treatments with LiCl, NaCl, and RbCl led to an increase in microstrain and faster degradation. The compressive strain at the perovskite surface was the smallest for CsCl and was linked to improved stability. First-principles density functional theory calculations confirm the preferential formation of alkali defects at interstitial positions at th

SUBMITTER: Lee DK 

PROVIDER: S-EPMC11834145 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature