Zanetta Andrea, Andaji-Garmaroudi Zahra, Pirota Valentina, Pica Giovanni, Kosasih Felix Utama, Gouda Laxman, Frohna Kyle, Ducati Caterina, Doria Filippo, Stranks Samuel D, Grancini Giulia
Department of Chemistry & INSTM, Università di Pavia, Via T. Taramelli 14, Pavia, 27100, Italy.
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK.
Adv Mater. 2022 Jan;34(1):e2105942. doi: 10.1002/adma.202105942. Epub 2021 Oct 17.
Halide perovskite materials offer an ideal playground for easily tuning their color and, accordingly, the spectral range of their emitted light. In contrast to common procedures, this work demonstrates that halide substitution in Ruddlesden-Popper perovskites not only progressively modulates the bandgap, but it can also be a powerful tool to control the nanoscale phase segregation-by adjusting the halide ratio and therefore the spatial distribution of recombination centers. As a result, thin films of chloride-rich perovskite are engineered-which appear transparent to the human eye-with controlled tunable emission in the green. This is due to a rational halide substitution with iodide or bromide leading to a spatial distribution of phases where the minor component is responsible for the tunable emission, as identified by combined hyperspectral photoluminescence imaging and elemental mapping. This work paves the way for the next generation of highly tunable transparent emissive materials, which can be used as light-emitting pixels in advanced and low-cost optoelectronics.
卤化物钙钛矿材料为轻松调节其颜色以及相应地调节其发射光的光谱范围提供了一个理想的平台。与常规方法不同，这项工作表明，在Ruddlesden-Popper钙钛矿中进行卤化物取代不仅能逐步调节带隙，还可以成为控制纳米级相分离的有力工具——通过调整卤化物比例，进而调整复合中心的空间分布。结果，制备出了富含氯的钙钛矿薄膜，肉眼看来是透明的，且在绿色区域具有可控的可调谐发射。这是由于用碘化物或溴化物进行合理的卤化物取代导致了相的空间分布，其中次要成分负责可调谐发射，这是通过高光谱光致发光成像和元素映射相结合确定的。这项工作为下一代高度可调谐的透明发光材料铺平了道路，这些材料可用于先进且低成本的光电子学中的发光像素。
