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Tunable Broad Light Emission from 3D "Hollow" Bromide Perovskites through Defect Engineering
Ioannis Spanopoulos1, Ido Hadar1, Weijun Ke1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|April 27, 2021
Summary
Engineered novel 3D "hollow" bromide perovskites with tunable optical properties. These defect-engineered materials exhibit stable, strong broad light emission, a first for 3D hybrid halide perovskites.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Optoelectronics
Background:
- Hybrid halide perovskites are promising for optoelectronics due to their structure.
- Perovskite stability is linked to cation size, but
- hollow
- perovskites offer extended stability.
Purpose of the Study:
- Engineer a new family of 3D
- hollow
- bromide perovskites.
- Investigate the structure-property relationships in these defective perovskites.
- Achieve tunable optical properties and stable light emission.
Main Methods:
- Synthesis of 3D
- hollow
- bromide perovskites with varying compositions.
- Pair distribution function analysis for local structural characterization.
- Optical property measurements, including band gap tuning and photoluminescence quantum yield (PLQY).
Main Results:
- Successfully synthesized 3D
- hollow
- bromide perovskites with general formula (FA)1-x(en)x(Pb)1-0.7(Br)3-0.4.
- Observed a wide distribution of Pb-Pb distances due to defects and ethylenediammonium (en2+) inclusion.
- Tuned the band gap from 2.20 to 2.60 eV and achieved stable, strong broad light emission (1% PLQY) at higher en incorporation.
Conclusions:
- Meticulous defect engineering is effective for customizing optical properties of hybrid halide perovskites.
- The engineered
- hollow
- perovskites demonstrate unprecedented stable broad light emission.
- These findings open new avenues for 3D hybrid halide perovskites in optoelectronic applications.
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