Expanded Analogs of Three-Dimensional Lead-Halide Hybrid Perovskites.,Angewandte Chemie International Edition

当前位置： X-MOL 学术 › Angew. Chem. Int. Ed. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Expanded Analogs of Three-Dimensional Lead-Halide Hybrid Perovskites.
Angewandte Chemie International Edition ( IF 16.1 ) Pub Date : 2020-07-10 , DOI: 10.1002/anie.202005012
Daiki Umeyama _{1,

2} , Linn Leppert ₃ , Bridget A Connor ₁ , Mary Anne Manumpil ₁ , Jeffrey B Neaton _{4,

5,

6} , Hemamala I Karunadasa _{1,

7}

Affiliation

Replacing the Pb−X octahedral building unit of A^IPbX₃ perovskites (X=halide) with a pair of edge‐sharing Pb−X octahedra affords the expanded perovskite analogs: A^IIPb₂X₆. We report seven members of this new family of materials. In 3D hybrid perovskites, orbitals from the organic molecules do not participate in the band edges. In contrast, the more spacious inorganic sublattice of the expanded analogs accommodates larger pyrazinium‐based cations with low‐lying π* orbitals that form the conduction band, substantially decreasing the band gap of the expanded lattice. The molecular nature of the conduction band allows us to electronically dope the materials by reducing the organic molecules. By synthesizing derivatives with A^II=pyridinium and ammonium, we can isolate the contributions of the pyrazinium‐based orbitals in the band gap transition of A^IIPb₂X₆. The organic‐molecule‐based conduction band and the inorganic‐ion‐based valence band provide an unusual electronic platform with localized states for electrons and more disperse bands for holes upon optical or thermal excitation.

中文翻译：

三维卤化铅杂钙钛矿的扩展类似物。

用一对边缘共享的Pb-X八面体代替A ^I PbX ₃钙钛矿的Pb-X八面体结构单元（X =卤化物），提供了扩展的钙钛矿类似物：A ^II Pb ₂ X ₆。我们报告了这一新材料家族的七名成员。在3D杂化钙钛矿中，有机分子的轨道不参与能带边缘。相比之下，扩展后的类似物更宽敞的无机亚晶格可容纳较大的基于吡嗪鎓的阳离子，这些阳离子具有形成传导带的低π*轨道，从而大大减小了扩展后的晶格的带隙。导带的分子性质使我们能够通过还原有机分子对材料进行电子掺杂。通过合成具有A ^II =吡啶鎓和铵的衍生物，我们可以分离出吡嗪鎓基轨道对A ^II Pb ₂ X ₆的带隙跃迁的贡献。基于有机分子的导带和基于无机离子的价带提供了一个不寻常的电子平台，具有电子的局域态和光或热激发时的空穴分散带。

更新日期：2020-07-10

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11