Organic–inorganic hybrid perovskites are developed to pursue high charge carrier mobility and light absorption coefficient. In this study, we present a detailed comparative research of the atomic and electronic structures of single-layered perovskites (C₄H₉NH₃)₂PbBr₄ with two-dimensional/three-dimensional (2D/3D) spatial arrangement to predict the in plane charge carrier mobility along with the charge effective mass, elastic constant, and deformation potential. The calculated results reveal that the intrinsic in plane carrier mobilities of 2D single-layered hybrid perovskite (C₄H₉NH₃)₂PbBr₄ along the 〈100〉 and 〈010〉 directions are superior to those of the 3D structure. Furthermore, the optical properties are calculated from the electronic structure; it is found that the light absorption spectrum of 2D single-layered perovskite (C₄H₉NH₃)₂PbBr₄ with a high absorption coefficient is wider than that of the 3D phase. We speculate that the superior mobility and wider absorption spectrum of the 2D mono-layered perovskite are due to high charge density and ferroelectricity originating from structure distortion upon 3D-to-2D structure transformation. These results indicate that the 2D single-layered hybrid perovskite (C₄H₉NH₃)₂PbBr₄ is a potential candidate for application in the optoelectronic and photovoltaic fields.

中文翻译：

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二维单层杂化钙钛矿（C ₄ H ₉ NH ₃）₂ PbBr _4的高迁移率和出色的光学性质：理论研究†

有机-无机杂化钙钛矿的开发是为了追求高载流子迁移率和光吸收系数。在这项研究中，我们将对具有二维/三维（2D / 3D）空间排列的单层钙钛矿（C ₄ H ₉ NH ₃）₂ PbBr ₄的原子和电子结构进行详细的比较研究，以预测平面中的电荷载流子迁移率以及电荷有效质量，弹性常数和变形势。计算结果表明，二维单层杂化钙钛矿（C ₄ H ₉ NH ₃）₂ PbBr ₄的内在平面载流子迁移率是固有的。沿<100>和<010>方向的方向优于3D结构的方向。此外，光学性质是根据​​电子结构计算得出的。发现具有高吸收系数的2D单层钙钛矿（C ₄ H ₉ NH ₃）₂ PbBr ₄的光吸收光谱比3D相的吸收光谱宽。我们推测2D单层钙钛矿的优异迁移率和更宽的吸收光谱是由于3D到2D结构转换时源自结构变形的高电荷密度和铁电引起的。这些结果表明2D单层杂化钙钛矿（C ₄ H ₉ NH ₃）₂ PbBr ₄是在光电子和光伏领域中应用的潜在候选者。