Elevating Perovskite Solar Cells: Advances in Scalable Thin Film Deposition and Degradation Insights

In the rapidly evolving landscape of perovskite solar cells (PSCs), two pivotal challenges take center stage: (i) pioneering scalable thin film deposition techniques and (ii) unraveling degradation mechanisms. This presentation converges groundbreaking research encompassing scalable thin film deposition, high-efficiency solar cells, in-situ synchrotron X-ray diffraction studies, spatially resolved photoluminescence analysis, and accelerated degradation investigations under maximum power point tracking conditions.<br/><br/>At the heart of this presentation lies the development of scalable thin film deposition techniques, with a special emphasis on the innovative Verde Slot Coater [Ref 1]. Engineered to bring perovskite solar cells closer to commercial viability, the Verde Slot Coater represents a significant leap forward. It addresses the challenges of achieving uniform coating and effectively bridges the gap between laboratory-scale experiments and large-scale production. Most notably, this innovation has resulted in achieving over 18% power conversion efficiency (PCE) for 1.25 cm² solar cells, underlining the potential of scalable manufacturing methods within the perovskite industry.<br/><br/>We have also embarked on a journey towards long-term stability, guided by cutting-edge research methodologies. Specifically, we have begun studies of Formamidinium Lead Iodide (FAPI) thin film devices. FAPI is slightly unstable with a Goldschmidt tolerance factor just above 1.0, making it susceptible to transforming into the undesirable hexagonal phase. Through in-situ synchrotron X-ray diffraction studies, we gain invaluable insights into the degradation processes that influence perovskite thin films over time. This research enables us to track the evolution of multiple phases over time, exploring responses to varying conditions such as temperature, light exposure, and humidity, across timescales from seconds to hours.<br/><br/>In the race to ensure PSCs can endure real-world challenges, accelerated degradation studies conducted under maximum power point tracking conditions provide indispensable insights. These studies simulate practical scenarios, enabling researchers to evaluate the resilience of perovskite solar cells and optimize their performance for long-term reliability. Furthermore, the use of spatially resolved photoluminescence studies (SRPL) during accelerated degradation investigations offers a microscopic understanding of degradation with a spatial resolution of 1 micron. By pinpointing specific regions of degradation and identifying potential mitigation strategies, this research substantially contributes to the long-term durability of perovskite solar cells.<br/><br/>The presentation will provide the latest results for each facet of the research outlined above. It encapsulates the spirit of innovation in perovskite solar cell research, emphasizing scalable manufacturing, high efficiency, and an in-depth exploration of degradation mechanisms. It invites us to closely scrutinize the path toward more robust and commercially viable perovskite solar cells.<br/><br/>Ref 1: Wan, J., Li, Y., Benson, J., Miller, R., Zhernenkov, M., Freychet, G. & Headrick, R. L. Dynamic processes in transient phases during self-assembly of organic semiconductor thin films. Molecular Systems Design & Engineering 7, 34-43, doi: https://doi.org/10.1039/D1ME00078K (2022).