Laboratory of New Materials for Photovoltaic Energy, Institut de Disseny I Fabricacio, Universitat Politecnica, Valencia, Spain; Laboratory of Fundamental and Applied Sciences Research and Training Unit, University Nanguy Abrogoua, Côte d'Ivoire.
Laboratory of New Materials for Photovoltaic Energy, Institut de Disseny I Fabricacio, Universitat Politecnica, Valencia, Spain.
J Mol Graph Model. 2023 Nov;124:108559. doi: 10.1016/j.jmgm.2023.108559. Epub 2023 Jul 6.
Herein, we investigated the stability of lead halide perovskites under ambient conditions after mixing the two cations Formamidinium (FA) and Cesium (Cs). The CsFAPbI perovskites solutions were prepared with different contents of x (0.0, 0.3, 0.5, 0.7 and 1.0) and deposited on substrates by spin-coating technique. The CsFAPbI films were, afterwards, characterized using the X-ray diffraction (XRD), UV-visible spectroscopy, photoluminescence (PL) spectra and scanning electron microscopy (SEM) to figure out their crystallinity, morphology, and optical properties. We noticed a stable perovskite structure for the mixed compounds unalike the pure FA and Cs films. The XRD analysis revealed, even after two weeks, the growth and good stability after two weeks of the desired black cubic α-phase perovskite structure in opposite to FAPbI and CsPbI which, respectively, showed faster degradation and transition into non-perovskite δ-phase and ɣ-phase no perovskite phases. The mixed perovskites Cs-FA also displayed a high absorbance especially for the ones with 30% of Cs and 70% of FA or 50% of each, with an excellent band gap energy ranging between 1.52 and 1.7 eV where FAPbI and CsPbI were showing a bandgap between 1.5 and 1.9 eV respectively. Moreover, the performance of the CsFAPbI based solar cells were simulated with SCAPS by using the band gaps obtained from the experimental study and after by varying the band gap, the thickness of the absorber layers and then different types of Electron Transport Layer (ETL). The simulation results revealed that the CsFAPbI based solar cells had the highest higher efficiency around 22.36%.
在此，我们研究了在将两种阳离子甲脒（FA）和铯（Cs）混合后，卤化铅钙钛矿在环境条件下的稳定性。通过旋涂技术将 CsFAPbI 钙钛矿溶液制备不同含量的 x（0.0、0.3、0.5、0.7 和 1.0）并沉积在基底上。随后，使用 X 射线衍射（XRD）、紫外-可见光谱、光致发光（PL）光谱和扫描电子显微镜（SEM）对 CsFAPbI 薄膜进行了表征，以确定其结晶度、形貌和光学性质。我们注意到混合化合物具有稳定的钙钛矿结构，而不同于纯 FA 和 Cs 薄膜。XRD 分析表明，即使在两周后，所需的黑色立方α相钙钛矿结构也能保持良好的稳定性，而 FAPbI 和 CsPbI 则分别表现出更快的降解和向非钙钛矿δ相和γ相的转变，没有出现钙钛矿相。混合钙钛矿 Cs-FA 也表现出高吸收率，特别是 Cs 含量为 30%、FA 含量为 70%或各占 50%的混合钙钛矿，带隙能在 1.52 到 1.7 eV 之间，而 FAPbI 和 CsPbI 的带隙分别在 1.5 和 1.9 eV 之间。此外，通过使用从实验研究中获得的带隙以及通过改变带隙、吸收层的厚度和不同类型的电子传输层（ETL），使用 SCAPS 对基于 CsFAPbI 的太阳能电池的性能进行了模拟。模拟结果表明，基于 CsFAPbI 的太阳能电池的效率最高，约为 22.36%。
