Perini Carlo Andrea Riccardo, Rojas-Gatjens Esteban, Ravello Magdalena, Castro-Mendez Andrés-Felipe, Hidalgo Juanita, An Yu, Kim Sanggyun, Lai Barry, Li Ruipeng, Silva-Acuña Carlos, Correa-Baena Juan-Pablo
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Adv Mater. 2022 Dec;34(51):e2204726. doi: 10.1002/adma.202204726. Epub 2022 Nov 11.
The impact of the bulky-cation-modified interfaces on halide perovskite solar cell stability is underexplored. In this work, the thermal instability of the bulky-cation interface layers used in the state-of-the-art solar cells is demonstrated. X-ray photoelectron spectroscopy and synchrotron-based grazing-incidence X-ray scattering measurements reveal significant changes in the chemical composition and structure at the surface of these films that occur under thermal stress. The changes impact charge-carrier dynamics and device operation, as shown in transient photoluminescence, excitation correlation spectroscopy, and solar cells. The type of cation used for surface treatment affects the extent of these changes, where long carbon chains provide more stable interfaces. These results highlight that prolonged annealing of the treated interfaces is critical to enable reliable reporting of performances and to drive the selection of different bulky cations.
大体积阳离子修饰界面卤化物钙钛矿太阳能电池稳定性的影响尚未得到充分研究。在这项工作中，证明了目前最先进的太阳能电池中使用的大体积阳离子界面层的热不稳定性。X射线光电子能谱和基于同步加速器的掠入射X射线散射测量揭示了这些薄膜表面在热应力下发生的化学成分和结构的显著变化。如瞬态光致发光、激发相关光谱和太阳能电池所示，这些变化影响电荷载流子动力学和器件运行。用于表面处理的阳离子类型会影响这些变化的程度，长碳链提供更稳定的界面。这些结果强调，处理后的界面长时间退火对于可靠报告性能和推动不同大体积阳离子的选择至关重要。
