Role of Alkali-Metal Cations in Electronic Structure and Halide Segregation of Hybrid Perovskites.

ABSTRACT: The ability to control or prevent phase segregation in perovskites is crucial to realizing stable and tunable mixed-halide optoelectronic devices. In this work, we systematically examine the impact of alkali-metal-cation (Cs⁺ and K⁺) concentration on the band structure, chemical composition, phase segregation, and polycrystalline microstructure on formamidinium-dominated mixed-halide mixed-cation perovskite films. It was found that the incorporation of Cs⁺ and K⁺ cations decreases the work function and the core levels of all components shift toward higher binding energy consistent with n-doping the perovskite film, which facilitates electron transfer to the electron transport layer TiO₂. A concentration-dependent film structure was obs

SUBMITTER: Zhang S 

PROVIDER: S-EPMC11956837 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature