Pressure-Induced Excimer Emission Enhancement From 0.3 GPa to 1.4 GPa in 1-((4-(Tert-butyl)Phenyl)Sulfinyl)Pyrene Crystals.

Pressure-induced emission enhancement (PIEE) in organic luminescent aggregates has attracted considerable attention due to its potential applications in the field of optoelectronics. However, studies on pressure-induced fluorescence enhancement in pyrene-centered systems have been limited, and the underlying mechanism is still not well understood. By comparing the piezochromic luminescent behaviors of excimers in two pyrene derivatives, this study demonstrates that the introduction of S═O bonds in Py-SO crystals plays a role of notable steric hindrance, which effectively modulates molecular packing. With increasing pressure, the vibration of S═O bonds is suppressed due to strengthened intermolecular interactions, which reduces non-radiative transitions and enhances the fluorescence intensity of Py-SO crystals notably from 0.3 to 1.4 GPa. The observed sensitive emission enhancement under low-pressure conditions provides new insights into advancing the application of pyrene-based materials in developing high-performance luminescent devices.