Photophysical properties of novel fluorescent thin solid layers based on the Aggregation Induced Emission of alkoxy-substituted salicylaldehyde azines

Highlights: • An uniform, fluorescent thin films using solvent methods have been created. • Self-organization of the molecules in the layer depends on the alkoxy substituent. • Small-molecule SAAs derivatives can be successfully used for the preparation of ink. • The production of a fluorescent layer with a modern printing method has been shown. A series of salicylaldehyde azines substituted with linear and branched alkoxy chains were synthesized and characterized. All derivatives exhibited photoluminescence in the thin layers due to Aggregation Induced Emission (AIE) properties. Ability to self-organizing of the azines in the thin solid layer deposited via evaporation, spin-coating and inkjet printing techniques, due to the nature of the substituent was investigated. The electronic properties, that is, orbital energies and resulting energy gap were calculated theoretically by density functional theory (DFT). On the selected examples inkjet inks were prepared and printed smooth uniform fluorescent layers appropriate for organic light emitting diodes (OLEDs).