Lian Linyuan, Zhang Peng, Zhang Xiuwen, Ye Qi, Qi Wei, Zhao Long, Gao Jianbo, Zhang Daoli, Zhang Jianbing
School of Optical and Electronic Information, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074, China.
College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
ACS Appl Mater Interfaces. 2021 Dec 15;13(49):58908-58915. doi: 10.1021/acsami.1c18038. Epub 2021 Dec 3.
Zero-dimensional (0D) organic metal halides have attracted significant attention because of their exceptional structure tunability and excellent optical characteristics. However, controllable synthesis of a desirable configuration of metal halide species in a rational way remains a formidable challenge, and how the unique crystal structures affect the photophysical properties are not yet well understood. Here, a reasonable metal halide structural modulation strategy is proposed to realize near-unity photoluminescence quantum efficiency (PLQE) in 0D organic antimony halides. By carefully controlling the reaction conditions, both 0D (CHN)SbCl and (CHN)SbCl with different metal halide configurations can be prepared. (CHN)SbCl with pyramid-shaped [SbCl] species exhibits yellow emission with a near-unity PLQE of 96.8%, while (CHN)SbCl with seesaw-shaped [SbCl] species is not emissive at room temperature. Theoretical calculations indicate that the different photophysical properties of these two crystals can be attributed to the different symmetries of their crystal structures. (CHN)SbCl adopts a triclinic structure with -1 symmetry, while (CHN)SbCl possesses a monoclinic structure with 2/ symmetry, which has an inversion center, and thus the optical transitions between their band-edge states give a minimal dipole intensity because of their similar parity character. In addition, we also successfully synthesized (CHN)SbCl nanocrystals for the first time, which are particularly appealing for their solution processibility and excellent optical properties. Furthermore, (CHN)SbCl nanocrystals flexible composite film shows bright yellow emission under β-ray excitation, suggesting a strong potential of (CHN)SbCl for β-ray detection.
零维（0D）有机金属卤化物因其出色的结构可调控性和优异的光学特性而备受关注。然而，以合理的方式可控合成所需构型的金属卤化物物种仍然是一项艰巨的挑战，并且其独特的晶体结构如何影响光物理性质尚未得到很好的理解。在此，提出了一种合理的金属卤化物结构调制策略，以实现零维有机锑卤化物接近单位的光致发光量子效率（PLQE）。通过仔细控制反应条件，可以制备出具有不同金属卤化物构型的零维（CHN）SbCl和（CHN）SbCl。具有金字塔形[SbCl]物种的（CHN）SbCl呈现黄色发射，PLQE接近单位，为96.8%，而具有跷跷板形[SbCl]物种的（CHN）SbCl在室温下不发光。理论计算表明，这两种晶体不同的光物理性质可归因于其晶体结构的不同对称性。（CHN）SbCl采用具有-1对称性的三斜结构，而（CHN）SbCl具有具有2/对称性的单斜结构，该结构具有对称中心，因此它们的带边态之间的光学跃迁由于其相似的宇称特性而给出最小的偶极强度。此外，我们还首次成功合成了（CHN）SbCl纳米晶体，其溶液可加工性和优异的光学性质特别吸引人。此外，（CHN）SbCl纳米晶体柔性复合膜在β射线激发下显示出亮黄色发射，表明（CHN）SbCl在β射线检测方面具有强大的潜力。
