Tunable multicolor photoluminescence in metal–organic halides via pressure-treatment π–π interactions

Abstract

Organic luminescent materials exhibit great potential for pressure-induced tunable multicolor photoluminescence (PL) emission. However, it remains a significant challenge to realize stable multicolor PL emission at ambient conditions owing to the high flexibility and relatively weak intermolecular interactions. Herein, a pressure-induced strategy is proposed to disrupt the previously prohibited interlayer charge transfer (CT) in a one-dimensional (1D) metal–organic halide complex (MOH), which switches the emission pathway from n–π* transitions to interlayer charge transfer. Notably, the binuclear metal–organic halide complex (ZnCl-B) displays a broad PL tunability from deep blue (405 nm) to green (515 nm) through pressure treatment. Experimental characterization and theoretical calculation results confirm that the stronger steric hindrance in ZnCl-B stabilizes the spatial conformation of organic ligands after pressure treatment, which enables interlayer CT to dominate the emission channel and achieve tunable multicolor PL emission.