Kolokytha Christina, Lathiotakis Nektarios N, Kaltzoglou Andreas, Petsalakis Ioannis D, Tzeli Demeter
Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., GR-11635 Athens, Greece.
Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, GR-15784 Zografou, Greece.
Materials (Basel). 2025 Feb 6;18(3):726. doi: 10.3390/ma18030726.
In the present work, nine 'defect' perovskites with the chemical formula AZrX have been studied, where the A-site cations are a methylammonium cation, formamidinium cation, and trimethyl-sulfonium cation and the X-site anions are halogen, X = Cl, Br, and I. We employ periodic DFT calculations using GGA-PBE, MBJ, HSEsol, and HSE06 functionals. All studied compounds exhibit a wide-bandgap energy that ranges from 5.22 eV to 2.11 eV, while for some cases, geometry optimization led to significant structural modification. It was found that the increase in the halogen size resulted in a decrease in the bandgap energy. The choice of the organic A-site cation affects the bandgap as well, which is minimal for the methylammonium cation. Such semiconductors with organic cations may be utilized in optoelectronic devices, given the substantial benefit of solution processability and thin film formation compared to purely inorganic analogs, such as CsZrX.
在本研究中，我们对九种化学式为AZrX的“缺陷”钙钛矿进行了研究，其中A位阳离子为甲铵阳离子、甲脒阳离子和三甲基锍阳离子，X位阴离子为卤素，X = Cl、Br和I。我们使用GGA-PBE、MBJ、HSEsol和HSE06泛函进行周期性密度泛函理论计算。所有研究的化合物都表现出5.22电子伏特至2.11电子伏特的宽带隙能量，而在某些情况下，几何优化导致了显著的结构改性。研究发现，卤素尺寸的增加导致带隙能量降低。有机A位阳离子的选择也会影响带隙，对于甲铵阳离子来说带隙最小。与纯无机类似物（如CsZrX）相比，这类含有机阳离子的半导体由于具有溶液可加工性和薄膜形成的显著优势，可用于光电器件。
