Chen Bin, Liu Zhou, Meng Ke, Qiao Zhi, Zhai Yufeng, Yu Runze, Wu Lin, Xiao Mingyue, Pan Li, Zheng Liya, Chen Gang
School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
Nano Lett. 2022 Oct 12;22(19):7826-7833. doi: 10.1021/acs.nanolett.2c02473. Epub 2022 Sep 22.
Precise control of crystal orientation in two-dimensional (2D) layered perovskites (LPs) is vital for their optoelectronic applications due to the structure-induced anisotropy in optical and electrical properties. Herein, we directly observe and control the crystal orientation of the butylammonium-based 2D LP films. Employing the synchrotron-based in situ grazing-incidence X-ray diffraction technique, we reveal the orientation modulation mechanism of the Cl additive by following the crystallization dynamics and chemical conversion pathways during film formation. Two new Cl-related intermediates are identified which serve as templates directing the orientational growth of the 2D LP films. We fine-tune the crystal orientation of 2D LP films through the Cl additive and incorporate the films with the requisite crystal orientations in solar cells and photodetectors. The optoelectronic performances of the devices show a strong correlation with the crystal orientation of the 2D LP films.
由于二维（2D）层状钙钛矿（LP）的光学和电学性质存在结构诱导的各向异性，因此精确控制其晶体取向对其光电应用至关重要。在此，我们直接观察并控制了基于丁基铵的二维LP薄膜的晶体取向。利用基于同步加速器的原位掠入射X射线衍射技术，通过跟踪薄膜形成过程中的结晶动力学和化学转化途径，我们揭示了Cl添加剂的取向调制机制。鉴定出两种新的与Cl相关的中间体，它们作为模板指导二维LP薄膜的取向生长。我们通过Cl添加剂微调二维LP薄膜的晶体取向，并将具有所需晶体取向的薄膜应用于太阳能电池和光电探测器中。器件的光电性能与二维LP薄膜的晶体取向密切相关。
