Deng Chenkai, Zhou Guojun, Chen Da, Zhao Jing, Wang Yonggang, Liu Quanlin
The Beijing Municipal Key Laboratory of New Energy Materials and Technologies, School of Materials Sciences and Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing 100094, China.
J Phys Chem Lett. 2020 Apr 16;11(8):2934-2940. doi: 10.1021/acs.jpclett.0c00578. Epub 2020 Mar 31.
Organic-inorganic hybrid perovskites have aroused intense research interest because of their excellent physical performance and potential for use in optoelectronic field. Herein, we report two new 2D hybrid lead bromides, (CHN)PbBr [CHN is 1,7-diaminoheptane] and (CHN)PbBr [CHN is 1,9-diaminononane], both of which possess ⟨100⟩-oriented inorganic layers consisting of corner-sharing octahedra. The optical bandgaps are experimentally determined to be 2.76 eV for (CHN)PbBr and 2.78 eV for (CHN)PbBr. Upon 390 nm excitation, (CHN)PbBr exhibits white-light emission centered at 600 nm, and (CHN)PbBr exhibits red-light emission centered at 620 nm. These broad photoluminescent spectra originate from the synergistic emission of free excitons (FEs) and self-trapped excitons (STEs). This work provides a strategy for realizing single-component white-light emission and efficient red-light emission in two-dimensional perovskites, demonstrating the vast application prospects of 2D perovskites in photoelectric devices.
有机-无机杂化钙钛矿因其优异的物理性能和在光电器件领域的应用潜力而引起了广泛的研究兴趣。在此，我们报道了两种新型的二维杂化溴化铅，(CHN)PbBr [CHN为1,7-二氨基庚烷] 和(CHN)PbBr [CHN为1,9-二氨基壬烷]，它们都具有由共角八面体组成的⟨100⟩取向无机层。通过实验测定，(CHN)PbBr的光学带隙为2.76 eV，(CHN)PbBr的光学带隙为2.78 eV。在390 nm激发下，(CHN)PbBr表现出以600 nm为中心的白光发射，(CHN)PbBr表现出以620 nm为中心的红光发射。这些宽的光致发光光谱源于自由激子（FEs）和自陷激子（STEs）的协同发射。这项工作为在二维钙钛矿中实现单组分白光发射和高效红光发射提供了一种策略，展示了二维钙钛矿在光电器件中的广阔应用前景。
