The synthesis of four new azo-Schiff base ligands from 2-hydroxy-3-methoxy-5-(phenyldiazenyl)benzaldehyde and 4-aminoantipyrine is described in this study. The molecular structures of all the scaffolds were confirmed using NMR spectroscopies such as 1 H and 13 C, as well as FT-IR and Mass spectroscopy. After successful synthesis and characterization of all the ligands, their in vitro antibacterial, antioxidant and anti-inflammatory activities were carried out by using standard protocols. Results revealed that all the four ligands (L1-L4) possessed excellent biological potency.

This work presents an investigation of three xanthone derivatives as the emitters for organic light-emitting diode applications. Through extensive photophysical and electrochemical studies, the thermally activated delayed fluorescence effect was observed and further applied in devices. Due to the substantial ΔEST gap, the final efficiency of the OLED was below 5%. The drop in the charge transfer energy was observed with electrochemical dimerisation of the donor molecule and increased molecule conjugation. The synthesised polymers exhibited an efficient thermally activated delayed fluorescence process through the shift of the singlet excited state energy level and decreased the ΔEST from 0.42 eV for the XNAP monomer material down to 0.12 eV for the polymerised derivative and final increase of the OLED device efficiency. Thus, the study presents the possibility of synthesising and tailoring many thermally activated delayed fluorescence emitters through electropolymerisation and applying this technique in working light-emitting devices.