Efficient deep blue emission by 4-styrylbenzonitrile derivatives in solid state: Synthesis, aggregation induced emission characteristics and crystal structures

Organic fluorescent molecules with pi-conjugated system have shown great importance in numerous applications including bioimaging and optoelectronics. Planar aggregation-induced emissive (AIE) organic compounds with efficient solid-state luminescence are rarely developed and urgently needed in various applications. In this work, highly planar 4-styrylbenzonitrile derivatives have been synthe-sized. Most of these compounds show strong AIE properties with hundred-fold fluorescent enhancement. Moreover, these molecules are deep blue emissive in solid state, exhibiting good to excellent fluorescence quantum efficiency. The single crystal analysis shows that adjacent molecules could form special J-type aggregation. The intramolecular rotations are efficiently restricted by various noncovalent interactions. These molecular arrangements could be essential for the observed strong emission in aggregated and solid state. This work has paved a new path to efficient AIE-active organic emitters with highly planar conformations from 4-styrylbenzonitrile structure. (C)& nbsp;2021 Elsevier B.V. All rights reserved.& nbsp;

Automated summary

Organic fluorescent molecules with pi-conjugated system have significant importance in applications such as bioimaging and optoelectronics. This study successfully synthesized highly planar 4-styrylbenzonitrile derivatives and discovered their strong luminescent properties in the solid state.