Synergistic Enhancement of Luminescent and Ferroelectric Properties through Multi‐Clipping of Tetraphenylethenes

Abstract

AbstractSynergistically enhancing luminescent and ferroelectric (SELF) properties are observed from a tetraphenylethene (TP) substituted with clipping groups (C), where the C is consisting of a 4‐[3,5‐bis‐(3‐decyloxy‐styryl)‐styryl]‐phenyl (DOS) unit. The DOS units of TPCn are self‐assembled via intermolecular interaction to clip themselves and induce TP aggregation, as evidenced by clip‐induced quenching of emission at DOS units (Eclip) accompanied by aggregation‐induced emission enhancement of TPs (EAIE). TPC4 demonstrates strong photoluminescence in a dilute chloroform solution and large EAIE in aqueous (>50%) THF solution. TPCn demonstrates SELF properties in film state, with high quantum yields of photoluminescence (>80%) and ferroelectric switching. Due to the introduction of four clips, TPC4 has a higher remnant polarization (Pr = 2.27 µC cm−2) at room temperature than TPC1. TPC4 is successfully employed in a light‐emitting electrochemical cell to achieve over 1290 cd m−2 under pulsed current conditions. The TPC4 film on a flexible substrate produced a piezoelectric output voltage of up to 0.13 V and a current density of 1.14 nA cm−2 upon bending. These results indicate that the side chain clipping and TP aggregation resulted in unprecedented flexible SELF properties in a single compound, offering simultaneous enhancement of electroluminescence, mechanical sensitivity, and energy harvesting capacity.