Short Aromatic Diammonium Ions Modulate Distortions in 2D Lead Bromide Perovskites for Tunable White-Light Emission
Short Aromatic Diammonium Ions Modulate Distortions in 2D Lead Bromide Perovskites for Tunable White-Light Emission
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DOI：
10.1021/acs.chemmater.2c02471
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发表时间：
2022-11-08
影响因子：
8.6
通讯作者：
Kanatzidis, Mercouri G.
中科院分区：
文献类型：
--
作者：
Fu, Ping;Quintero, Michael A.;Kanatzidis, Mercouri G.
低维卤化物钙钛矿在可见光范围内的白光宽带发射通常归因于溴化铅八面体中的结构畸变。本文报道了基于短芳香族二铵阳离子、对亚苯基二铵（pPDA）、间亚苯基二铵（mPDA）和两种以邻亚苯基二铵（oPDA）为模板的一维化合物的Dion-Jacobson相二维（2D）溴化铅钙钛矿。所有的化合物都表现出白光发射。单晶X-射线衍射分析表明，铅八面体的畸变是由阳离子的立体化学和它们与钙钛矿层的相互作用的影响。固态1H和207 Pb NMR光谱分析进一步证实了这一趋势，从而观察到不同的1H和207 Pb化学位移的pPDA和mPDA间隔阳离子，表明不同的氢键相互作用和八面体扭曲。由于八面体畸变，2D（mPDA）PbBr 4化合物表现出比2D（pPDA）PbBr 4更宽的白光发射。密度泛函理论计算表明，（pPDA）PbBr 4和（mPDA）PbBr 4是直接带隙半导体，它们的电子带隙和有效质量都比Ruddlesden-Popper相（BA）2 PbBr 4大。在这些化合物的膜中，2D（mPDA）PbBr 4显示出最好的稳定性，这归因于材料中较强的氢键相互作用。
White-light broadband emission in the visible range from the low-dimensional halide perovskites is commonly attributed to structural distortions in lead bromide octahedra. In this paper, we report Dion-Jacobson-phase two-dimensional (2D) lead bromide perovskites based on short aromatic diammonium cations, p-phenylene diammonium (pPDA), m-phenylene dia-mmonium (mPDA), and two 1D compounds templated by o-phenylene diammonium (oPDA). All of the compounds exhibit white-light emission. Single-crystal X-ray diffraction analysis reveals that the distortion of the Pb octahedra is influenced by the stereochemistry of the cations and their interactions with the perovskite layers. Solid-state 1H and 207Pb NMR spectroscopy analysis further confirms this trend, whereby different 1H and 207Pb chemical shifts are observed for the pPDA and mPDA spacer cations, indicating different hydrogen-bonding interactions and octahedral distortions. Owing to the octahedral distortion, 2D (mPDA)PbBr4 compounds exhibit broader white-light emission than 2D (pPDA)PbBr4. Density functional theory calculations suggest that (pPDA)PbBr4 and (mPDA)PbBr4 are direct-band-gap semiconductors, and they exhibit larger electronic band gaps and effective masses than the Ruddlesden-Popper-phase (BA)2PbBr4. Among the films of these compounds, 2D (mPDA)PbBr4 shows the best stability, which is attributed to stronger hydrogen-bonding interactions in the material.