Grimaldi Gianluca, Schuringa Imme, Geuchies Jaco J, Rigter Susan A, Hoekstra Tom, Versluis Jan, Hidalgo Juanita, Correa-Baena Juan-Pablo, van de Groep Jorik, Kim Heejae, Bonn Mischa, Ehrler Bruno
Center for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
Optoelectronics Section, Cavendish Laboratory, University of Cambridge, Cambridge CB2 1TN, U.K.
ACS Energy Lett. 2024 Nov 7;9(12):5771-5779. doi: 10.1021/acsenergylett.4c02300. eCollection 2024 Dec 13.
Quasi-2D perovskites have been pivotal in recent efforts to stabilize perovskite solar cells. Despite the stability boost provided when these materials are introduced in perovskite solar cells, little is known about the intrinsic light and environmental stability of quasi-2D perovskites. In this study, we characterize the photostability of exfoliated quasi-2D perovskite single crystals in air using photoluminescence, infrared, X-ray fluorescence, and energy-dispersive X-ray spectroscopy. Photoexcitation leads to severe material loss with oxygen as a prerequisite for material breakdown. The effect can be traced to the formation of reactive oxygen species, as demonstrated by increases in the photostability under oxygen-free conditions. We show the effect of combined passivation steps, showcasing the stability enhancement offered by 2D-capping layers in combination with an oxygen-free atmosphere. Our results reveal that the stability of illuminated quasi-2D perovskites depends critically on oxygen exposure, highlighting the importance of oxygen-blocking passivation strategies for stable 2D perovskite-based devices.
准二维钙钛矿在近期稳定钙钛矿太阳能电池的努力中起着关键作用。尽管将这些材料引入钙钛矿太阳能电池时能提高稳定性，但对准二维钙钛矿的固有光稳定性和环境稳定性却知之甚少。在本研究中，我们使用光致发光、红外、X射线荧光和能量色散X射线光谱对空气中剥离的准二维钙钛矿单晶的光稳定性进行了表征。光激发会导致严重的材料损失，氧气是材料分解的先决条件。这种效应可追溯到活性氧物种的形成，无氧条件下光稳定性的提高证明了这一点。我们展示了组合钝化步骤的效果，展示了二维封端层与无氧气氛相结合所提供的稳定性增强。我们的结果表明，光照下准二维钙钛矿的稳定性关键取决于氧气暴露，突出了氧阻挡钝化策略对稳定的二维钙钛矿基器件的重要性。
