Hot carrier solar cells (HCSC) have attracted extensive attention due to the efficient utilization of high-energy photons. Two-dimensional (2D) perovskites is one of the materials suitable as HCSC due to the hot phonon bottleneck effect as well as the quantum well structure. Providing methods to regulate the hot carrier cooling rate of 2D perovskites is crucial for further technological development. In this study, we systematically investigate the role of organic molecules in regulating hot carrier relaxation in 2D n = 1 perovskites through time-resolved spectroscopic measurements. The results of transient absorption and time-resolved photoluminescence reveal that hot carrier relaxation in 2D perovskites takes place on sub-picosecond time scales and can be effectively modulated by component engineering of organic molecules. These insightful results contribute to deep understanding of the hot carrier relaxation process of 2D perovskites and provide valuable information for the future development of higher performance perovskite solar cells.

Haoran Pang. Organic cation dependent hot carrier relaxation dynamics in two-dimensional perovskites. Academic Journal of Materials & Chemistry (2024) Vol. 5, Issue 1: 25-30. https://doi.org/10.25236/AJMC.2024.050105.

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