Pressure-induced emission of cesium lead halide perovskite nanocrystals.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30374042.
- Also identified by DOI 10.1038/s41467-018-06840-8 and PMC identifier 6206024.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Metal halide perovskites (MHPs) are of great interest for optoelectronics because of their high quantum efficiency in solar cells and light-emitting devices. However, exploring an effective strategy to further improve their optical activities remains a considerable challenge. Here, we report that nanocrystals (NCs) of the initially nonfluorescent zero-dimensional (0D) cesium lead halide perovskite Cs<sub>4</sub>PbBr<sub>6</sub> exhibit a distinct emission under a high pressure of 3.01 GPa. Subsequently, the emission intensity of Cs<sub>4</sub>PbBr<sub>6</sub> NCs experiences a significant increase upon further compression. Joint experimental and theoretical analyses indicate that such pressure-induced emission (PIE) may be ascribed to the enhanced optical activity and the increased binding energy of self-trapped excitons upon compression. This phenomenon is a result of the large distortion of [PbBr<sub>6</sub>]<sup>4-</sup> octahedral motifs resulting from a structural phase transition. Our findings demonstrate that high pressure can be a robust tool to boost the photoluminescence efficiency and provide insights into the relationship between the structure and optical properties of 0D MHPs under extreme conditions.