Investigation of Photostability in Perylene Diimide (PDI) Derivative Films by Continuous Quantum Yield Measurements.

Perylene diimides (PDIs) films have been widely explored due to their high fluorescence quantum yield, optoelectronic properties, and flat-conjugated structure, which allows efficient charge transport and light absorption. In this study, we investigated the photostability and quantum yield behavior of several PDI derivatives, specifically PDI-C3, PDI-C5, PDI-C8, and PDI-C13. A 447 nm optical laser was employed to assess the relative luminescence efficiency of these compounds under consistent experimental conditions. Based on our findings, different PDI derivatives exhibit distinct photostability trends, indicating that over time, quantum yield is enhanced when there are more carbon chains affixed to the PDI core. Furthermore, we identified a connection between structural alterations and quantum efficiency, which provides important insights for developing more stable and high-efficiency PDI-based materials in optoelectronic applications.