Bouferrache K, Ghebouli M A, Ghebouli B, Fatmi M, Ahmed Sameh I
Research Unit on Emerging Materials (RUEM), University Ferhat Abbas of Setif 1 Setif 19000 Algeria
Department of Physics, Faculty of Sciences, University of M'sila University Pole Road Bourdj Bou Arreiridj 28000 M'sila Algeria.
RSC Adv. 2025 Apr 17;15(15):11923-11933. doi: 10.1039/d5ra00862j. eCollection 2025 Apr 9.
Hybrid organic, halide, and divalent metal double perovskites K(Sn, Se, Te)Br with cubic structures were computationally evaluated using the generalized-gradient approximation (GGA) and modified Becke-Johnson (mBJ-GGA) functionals. The Goldschmidt tolerance factor, octahedral factor, Helmholtz free energy, and formation energy illustrated the structural, chemical, and thermodynamic stabilities of the studied compounds. The equilibrium lattice constants for KSeBr and KSnBr deviated from the experimental values by 4.3% and 3.1%, respectively. The elastic constants of K(Sn, Se, Te)Br were significantly smaller due to their larger reticular distances, lower Coulomb forces, and reduced hardness. The high dynamic lattice anharmonicity of K(Sn, Se, Te)Br reduced their electronic conductivity, providing a practical advantage in the presence of a thermoelectric field. K(Se, Te)Br were predicted to have indirect bandgaps of X-L nature, while KSnBr exhibited a direct - bandgap. The power conversion efficiency (PCE) for photovoltaic devices with K(Sn, Se, Te)Br perovskite compounds as solar absorbers reached 20.51%. Their absorption in the visible region provided an advantage in energy harvesting. The electronic transitions in the studied double perovskites took place between the Br-4p and K-4s orbitals. Thus, these hybrid organic-inorganic halide perovskites proved to be excellent semiconductors for photovoltaic applications and demonstrated optimized photovoltaic efficiency.
采用广义梯度近似（GGA）和修正的贝克-约翰逊（mBJ-GGA）泛函对具有立方结构的有机、卤化物和二价金属混合双钙钛矿K(Sn, Se, Te)Br进行了计算评估。戈尔德施密特容差因子、八面体因子、亥姆霍兹自由能和形成能说明了所研究化合物的结构、化学和热力学稳定性。KSeBr和KSnBr的平衡晶格常数分别与实验值相差4.3%和3.1%。K(Sn, Se, Te)Br的弹性常数显著较小，这是由于它们的网状距离较大、库仑力较低以及硬度降低。K(Sn, Se, Te)Br的高动态晶格非谐性降低了它们的电子电导率，在存在热电场的情况下提供了实际优势。预测K(Se, Te)Br具有X-L性质的间接带隙，而KSnBr表现出直接带隙。以K(Sn, Se, Te)Br钙钛矿化合物作为太阳能吸收剂的光伏器件的功率转换效率（PCE）达到20.51%。它们在可见光区域的吸收在能量收集方面具有优势。所研究的双钙钛矿中的电子跃迁发生在Br-4p和K-4s轨道之间。因此，这些有机-无机混合卤化物钙钛矿被证明是用于光伏应用的优秀半导体，并展示出优化的光伏效率。
