Damp heat–stable perovskite solar cells with tailored-dimensionality 2D/3D heterojunctions
Randi Azmi, Esma Ugur, Akmaral Seitkhan, Faisal Aljamaan, Anand S. Subbiah, Jiang Liu, George T. Harrison, Mohamad Insan Nugraha, Mathan K. Eswaran, Maxime Babics, Yuan Chen, Fuzong Xu, Thomas G. Allen, Atteq ur Rehman, Chien‐Lung Wang, Thomas D. Anthopoulos, Udo Schwingenschlögl, Michele De Bastiani, Erkan Aydın, Stefaan De Wolf
Abstract
If perovskite solar cells (PSCs) with high power conversion efficiencies (PCEs) are to be commercialized, they must achieve long-term stability, which is usually assessed with accelerated degradation tests. One of the persistent obstacles for PSCs has been successfully passing the damp-heat test (85°C and 85% relative humidity), which is the standard for verifying the stability of commercial photovoltaic (PV) modules. We fabricated damp heat-stable PSCs by tailoring the dimensional fragments of two-dimensional perovskite layers formed at room temperature with oleylammonium iodide molecules; these layers passivate the perovskite surface at the electron-selective contact. The resulting inverted PSCs deliver a 24.3% PCE and retain >95% of their initial value after >1000 hours at damp-heat test conditions, thereby meeting one of the critical industrial stability standards for PV modules.