Synthesis and characterization of 1-phenyl-3-(4-phenyl-[1,2,3]triazol-1-yl)-4-styryl-azetidin-2-one films for light-emitting applications

Abstract

Triazole derivatives have attracted considerable interest in OLEDs because of their electron transporting as well as hole blocking and/or exciton confining properties. To improve the quantum efficiency and lower the operating voltage of OLEDs, a novel derivative of triazole namely 1-phenyl-3-(4-phenyl-[1,2,3]triazol-1-yl)-4-styryl-azetidin-2-one (TAZ) has been designed as an electron transporting material. Thin films of TAZ have been prepared by the vacuum evaporation technique onto a glass substrate kept at different temperatures under different experimental conditions. These films have been systematically studied for their structural, optical and electrical properties. X-ray diffraction and FESEM studies of the films show an increase in crystallinity with an increase in the substrate temperature. The electrical resistance of these films is found to be 10 7 ohm at room temperature. Analysis of optical absorption measurements on the films indicate that the interband transition energies lie within 3.4–3.6 eV. These wide band gaps show that TAZ layers can work as a hole blocking (HB) material in OLED.