标题： 揭示使用多体微扰理论对 Cs$_{2}$AgM(III)Cl$_{6}$双钙钛矿中三价金属阳离子转变的影响 显示英文标题

标题： Unveiling the impact of trivalent metal cation transmutation on Cs$_{2}$AgM(III)Cl$_{6}$ double perovskites using many-body perturbation theory

摘要： 无铅卤化双钙钛矿 A$_{2}$M(I)M(III)X$_{6}$在过去十年中引起了广泛关注，作为 CsPbX$_{3}$钙钛矿的有希望的替代品，解决了与铅毒性及材料不稳定性相关的问题。 在本工作中，我们采用三价金属阳离子转变策略设计了一系列无机无铅卤化双钙钛矿 Cs$_{2}$AgM(III)Cl$_{6}$，并对它们在光电设备中的应用潜力进行了全面研究。 我们的第一性原理计算基于密度泛函理论，表明这些材料具有面心立方晶格结构，同时表现出显著的热力学、动力学和机械稳定性。 G$_{0}$W$_{0}$@PBE 电子带隙范围为 1.47-6.20 eV，而 Bethe-Salpeter 方程 (BSE) 表明这些化合物在近红外到紫外区域具有强烈的光学吸收。 此外，激子特性表明这些钙钛矿表现出中等激子结合能（0.17 到 0.60 eV）和通常较长的激子寿命，除了 M(III) = Sc, Y, Tb 和 Lu 的材料。 Fröhlich 模型表明这些材料表现出中等到强的载流子-声子相互作用，其中空穴-声子耦合比电子-声子耦合更为显著。 有趣的是，发现电荷分离的极化子态比束缚激子态更不稳定，在这些材料中，电子的极化子迁移率更高（4.92-29.03 cm$^{2}$V$^{-1}$s$^{-1}$），高于空穴的迁移率（0.56-8.69 cm$^{2}$V$^{-1}$s$^{-1}$）。 总体而言，我们的研究证明，在Cs$_{2}$AgM(III)Cl$_{6}$中三价金属阳离子的转变能够创建具有优异、可调光电特性的稳定无铅卤化双钙钛矿，使其非常适合柔性光电应用。 显示英文摘要

摘要： Lead-free halide double perovskites A$_{2}$M(I)M(III)X$_{6}$ have garnered significant attention in the past decade as promising alternatives to CsPbX$_{3}$ perovskites, addressing concerns related to lead toxicity and material instability. In this work, we employ a trivalent metal cation transmutation strategy to design a series of inorganic Pb-free halide double perovskites Cs$_{2}$AgM(III)Cl$_{6}$ and perform a comprehensive investigation into their potential for applications in optoelectronic devices. Our first-principles calculations, rooted in density functional theory, demonstrate that these materials possess a face-centered cubic lattice structure while showcasing remarkable thermodynamic, dynamical, and mechanical stability. The G$_{0}$W$_{0}$@PBE electronic bandgap ranges from 1.47-6.20 eV, while the Bethe-Salpeter equation (BSE) indicates strong optical absorption spanning near-infrared to ultraviolet regions for these compounds. Furthermore, the excitonic properties suggest that these perovskites exhibit intermediate exciton binding energies (0.17 to 0.60 eV) and generally longer exciton lifetimes, except for the materials with M(III) = Sc, Y, Tb, and Lu. The Fr\"ohlich model indicates that these materials exhibit intermediate to strong carrier-phonon interactions, with hole-phonon coupling more prominent than electron-phonon coupling. Interestingly, the charge-separated polaronic states are found to be less stable than the bound exciton states, with higher polaron mobility for electrons (4.92-29.03 cm$^{2}$V$^{-1}$s$^{-1}$) than for holes (0.56-8.69 cm$^{2}$V$^{-1}$s$^{-1}$) in these materials. Overall, our study demonstrates that trivalent metal cation transmutation in Cs$_{2}$AgM(III)Cl$_{6}$ enables the creation of stable and lead-free halide double perovskites with exceptional, tunable optoelectronic properties, making them ideal for flexible optoelectronic applications.