New fluorescent material based on anthracene and triazole for blue organic light emitting diode: A combined experimental and theoretical study

Abstract New functional anthracene material (An-Tri-Van) was elaborated through click chemistry reaction to be applied as an emitter in blue OLEDs. We have performed a combined experimental and theoretical study to get insights into the optoelectronic properties of the new organic material An-Tri-Van. Its molecular structure was confirmed by proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared (FT-IR) spectroscopies. Thermal analysis was determined by DSC and showed that this material has a good thermal stability up to 200 °C. The optical properties for UV-Vis absorption and photoluminescence (PL) of An-Tri-Van were investigated in dilute solution and in thin film. The HOMO and LUMO energy levels were estimated using cyclic voltammetry analysis. Density Functional Density (DFT) and Time Dependent (TD-DFT) have been used to evaluate the structural, optical and charge transfer properties of the studied organic material. The B3LYP method at 3-21g (d), 6-31+g (d) and 6-311++g (d, p) basis sets have been successfully applied to reliably compare predicted vibrational, structural, electrochemical and optical properties. The studied molecule exhibited a non-planar structure with energy band gap around 3.4 eV and a vibronic structure of absorption in the ultraviolet-near visible with a maximum absorption of 402 nm attributed to the π → π ∗ electronic transitions mainly from anthracene group. The excited An-Tri-Van displayed a purely blue color emission. Based on Marcus theory and starting from the analysis of the charge transfer properties, we found that the molecule An-Tri-Van possess an interesting hole/electron transport ability. In addition, the current-voltage response (I-V) characteristic of typical three-layer OLED (ITO/ NPB/An-Tri-Van/ Alq3/ Al) was generated by simulation and the threshold voltage is estimated to be 5.4 V. The prepared An-Tri-Van molecule has tunable electronic and physical properties that exhibit the most favorable characteristics for blue OLED emission.