Shargaieva Oleksandra, Kuske Lena, Rappich Jörg, Unger Eva, Nickel Norbert H
Young Investigator Group "Hybrid Materials Formation and Scaling", Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Kekuléstr. 5, 12489, Berlin, Germany.
Interdisziplinäres Zentrum für Materialwissenschaften, Martin-Luther Universität, Heinrich-Damerow-Str. 4, 06120, Halle, Germany.
Chemphyschem. 2020 Oct 16;21(20):2327-2333. doi: 10.1002/cphc.202000479. Epub 2020 Sep 30.
In this work, we present a detailed investigation of the optical properties of hybrid perovskite building blocks, [PbI ] , that form in solutions of CH NH PbI and PbI . The absorbance, photoluminescence (PL) and photoluminescence excitation (PLE) spectra of CH NH PbI and PbI solutions were measured in various solvents and a broad concentration range. Both CH NH PbI and PbI solutions exhibit absorption features attributed to [PbI ] and [PbI ] complexes. Therefore, we propose a new mechanism for the formation of polymeric polyiodide plumbates in solutions of pristine PbI . For the first time, we show that the [PbI ] species in both solutions of CH NH PbI and PbI exhibit a photoluminescence peak at about 760 nm. Our findings prove that the spectroscopic properties of both CH NH PbI and PbI solutions are dominated by coordination complexes between Pb and I . Finally, the impact of these complexes on the properties of solid-state perovskite semiconductors is discussed in terms of defect formation and defect tolerance.
在这项工作中，我们详细研究了混合钙钛矿结构单元[PbI]在CH₃NH₃PbI和PbI₂溶液中形成的光学性质。在各种溶剂和较宽的浓度范围内测量了CH₃NH₃PbI和PbI₂溶液的吸光度、光致发光（PL）和光致发光激发（PLE）光谱。CH₃NH₃PbI和PbI₂溶液均表现出归因于[PbI]和[PbI]络合物的吸收特征。因此，我们提出了一种在原始PbI₂溶液中形成聚合多碘酸铅的新机制。首次表明，CH₃NH₃PbI和PbI₂溶液中的[PbI]物种在约760 nm处均表现出光致发光峰。我们的研究结果证明，CH₃NH₃PbI和PbI₂溶液的光谱性质均由Pb和I之间的配位络合物主导。最后，从缺陷形成和缺陷容忍度方面讨论了这些络合物对固态钙钛矿半导体性质的影响。
