论文标题
关于咖啡因在Mapbi3钙钛矿表面上的吸附机制：联合UMC--DFT研究
On the Adsorption Mechanism of Caffeine on MAPbI3 Perovskite Surfaces: A Combined UMC--DFT Study
论文作者
论文摘要
最近，经过实验表明，在吸附咖啡因的分子层时，钙钛矿mapbi $ _3 $的性能和热稳定性得到了改善。在这项工作中，我们使用了一种混合方法，该方法结合了未耦合的蒙特卡洛（UMC）和密度功能理论（DFT）模拟，对Mapbi $ _3 $的表面上的咖啡因分子的吸附机制进行了详细而全面的研究。我们的结果表明，咖啡因分子在mapbi $ _3 $表面上的吸附距离和能量分别为2.0Å和-0.3 eV。咖啡因/Mapbi $ _3 $配合物的直接带盖为2.38 eV，两个扁平的内部内部带距离距离1.15和2.18 eV，距离价带的顶部。尽管咖啡因的存在并没有显着转移能级水平，但相互作用MAPBI $ _3 $/PEROVSKITE足以影响乐队的分散体，尤其是传统带。
Recently, it was experimentally shown that the performance and thermal stability of the perovskite MAPbI$_3$ were improved upon the adsorption of a molecular layer of caffeine. In this work, we used a hybrid methodology that combines Uncoupled Monte Carlo (UMC) and Density Functional Theory (DFT) simulations to carry out a detailed and comprehensive study of the adsorption mechanism of a caffeine molecule on the surface of MAPbI$_3$. Our results showed that the adsorption distance and energy of a caffeine molecule on the MAPbI$_3$ surface are 2.0 Å and -0.3 eV, respectively. The caffeine/MAPbI$_3$ complex presents a direct bandgap of 2.38 eV with two flat intragap bands distanced 1.15 and 2.18 eV from the top of valence bands. Although the energy band levels are not significantly shifted by the presence of caffeine, the interaction MAPbI$_3$/perovskite is enough to affect the bands' dispersion, particularly the conduction bands.
