Lead halide hybrid perovskite with typical formula ABX₃ has great application prospects in the field of optoelectronic devices due to their excellent characteristics, including easy processing, adjustable structure, tunable band gaps. In this work, we report three halogen-substituted lead halide hybrid perovskites, namely, (DBU) PbX₃ (DBU ​= ​1,8-diazabicyclo [5.4.0] undec-7-ene, X ​= ​Cl, Br, I). These hybrid compounds have similar one-dimensional chain perovskite structures and undergo above-room temperature solid to solid phase transition. The variation of the heavy halogen atoms from Cl, Br to I on the X site causes a gradually larger octahedral space, which contributes to the decrease in phase transition temperature, because of the confinement effect. Meanwhile, a reduction in the band gap occurs for (DBU) PbX₃ was obtained. This work highlights the halogen substitution on the lead halide hybrid perovskite towards excellent performance, which will benefit the field of optoelectronics.

具有典型分子式ABX ₃的卤化铅杂化钙钛矿由于具有易于加工、结构可调、带隙可调等优良特性，在光电器件领域具有广阔的应用前景。在这项工作中，我们报告了三种卤素取代的卤化铅杂化钙钛矿，即 (DBU) PbX ₃（DBU = 1,8-二氮杂双环 [5.4.0] undec-7-ene, X = Cl, Br, I）。这些杂化化合物具有相似的一维链钙钛矿结构，并经历高于室温的固相到固相转变。X 位点上重卤原子从 Cl、Br 到 I 的变化导致八面体空间逐渐变大，由于限制效应，这有助于相变温度的降低。同时，获得了(DBU) PbX ₃的带隙减小。这项工作突出了卤化铅杂化钙钛矿上的卤素取代，使其具有优异的性能，这将有利于光电子领域。