Kaur Gurpreet, Hameed Madsar, Lee Jae Eun, Elmestekawy Karim A, Johnston Michael B, Briscoe Joe, Herz Laura M
Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom.
School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom.
J Phys Chem Lett. 2025 Mar 6;16(9):2212-2222. doi: 10.1021/acs.jpclett.5c00041. Epub 2025 Feb 21.
FAPbI has emerged as a promising semiconductor for photovoltaic applications offering a suitable bandgap for single-junction cells and high chemical stability. However, device efficiency is negatively affected by intrinsic quantum confinement (QC) effects that manifest as additional peaks in the absorption spectra. Here, we show that aerosol-assisted crystallization is an effective method to improve crystallinity and suppresses regions exhibiting QC in FAPbI. We demonstrate that films with minimized QC effects exhibit markedly enhanced optoelectronic properties, such as higher charge-carrier mobilities and recombination lifetimes. Films crystallized under an aerosol solvent flow of either a mixture of ,-dimethylformamide and dimethyl sulfoxide or methylammonium thiocyanate vapor displayed reduced charge-carrier recombination losses and improved diffusion lengths compared to those of thermally annealed control films. Our study indicates clear correlations between suppression of QC features in absorption spectra with optimization of crystallinity and mitigation of internal strain, highlighting pathways toward high-performance solar cells.
FAPbI已成为一种有前景的用于光伏应用的半导体,为单结电池提供了合适的带隙和高化学稳定性。然而,器件效率受到本征量子限制(QC)效应的负面影响,这种效应在吸收光谱中表现为额外的峰。在此,我们表明气溶胶辅助结晶是一种提高结晶度并抑制FAPbI中出现QC区域的有效方法。我们证明,具有最小化QC效应的薄膜表现出显著增强的光电性能,如更高的电荷载流子迁移率和复合寿命。与热退火对照薄膜相比,在由N,N-二甲基甲酰胺和二甲基亚砜的混合物或硫氰酸甲铵蒸汽组成的气溶胶溶剂流中结晶的薄膜显示出降低的电荷载流子复合损失和改善的扩散长度。我们的研究表明,吸收光谱中QC特征的抑制与结晶度的优化和内部应变的减轻之间存在明显的相关性,突出了通往高性能太阳能电池的途径。