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Updated: Jun 6, 2025
11:38
Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
18.4K
Correlating Halide Segregation with Photolysis in Mixed-Halide Perovskites via In situ Opto-gravimetric Analysis.
Zhaojian Xu1, Xinjue Zhong1, Tuo Hu1
1Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|November 25, 2024
Summary
Quantitative measurement of halide oxidation in perovskite degradation is now possible. New opto-gravimetric methods reveal identical thresholds for iodide oxidation, segregation, and photolysis in mixed-halide perovskites.
Area of Science:
- Materials Science
- Photochemistry
- Solid-State Chemistry
Background:
- Halide oxidation is crucial for halide segregation and perovskite degradation.
- Quantitative measurement of halide oxidation in solid-state perovskites is difficult.
Purpose of the Study:
- To develop and apply a method for quantifying halide oxidation and photolysis kinetics in solid-state perovskites.
- To investigate the relationship between halide oxidation, segregation, and photolysis in mixed-halide perovskites.
- To elucidate the photolysis mechanism and its effect on perovskite film properties.
Main Methods:
- In situ opto-gravimetric measurements using a quartz crystal microbalance.
- Investigation of CsPb(BrxI1-x)3 perovskite series with varying bromide/iodide ratios.
Main Results:
- Opto-gravimetric measurements successfully quantified photolysis kinetics.
- Identical compositional thresholds (x ≈ 0.4) were found for iodide oxidation, light-induced halide segregation, and photolysis.
- Photolysis was shown to increase the n-type character of the perovskite film without lead reduction.
Conclusions:
- A powerful methodology for quantitative analysis of perovskite mass loss kinetics under operational and aging conditions was established.
- The study provides deeper insights into the mechanisms of perovskite degradation and light-induced instabilities.
- The findings correlate halide oxidation, segregation, and photolysis, explaining the photolysis mechanism in mixed-halide perovskites.
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