The Role of Ionic Migration and Cluster Formation in the Thermal Stability of CsFAPbI3 Perovskite Solar Cells

Abstract

This study investigates the composition-dependent thermal ionic stability of CsxFA1-xPbI3 perovskite solar cells (x = 0.05 and 0.20) under prolonged ISOS-D-2 thermal stress at 85°C. The findings reveal that while a lower cesium concentration maximizes room-temperature efficiency to 22.23%, higher cesium content suppresses grain-boundary ion migration through the formation of CsPbI3-rich cluster ionic sinks, demonstrating that room-temperature performance and thermal durability are completely decoupled parameters.

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References

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