Optoelectronic Exploration of Two Pyrazole-Based Oligomers: Synthesis, Characterization, Theoretical Calculations, and Optical Properties of Thin Films

Abstract

A detailed study of the optical properties of materials plays a critical role in the evaluation of functional applications. Understanding the impact on the optical behavior of pyrazole-based oligomer (PBO) films is crucial for optimizing their performance in various applications. To investigate this relationship, the first step involved synthesizing PBOs through a one-step reaction between diethyl 1-methyl-1H-pyrazole-3,5-dicarboxylate and p-phenylene-diamine, as well as o-phenylene-diamine. The synthesized PBOs were then characterized using FT-IR, 1H-NMR, TGA, and SEM techniques. Two thin films of PBOs were prepared via solution casting, with thicknesses of 13 µm and 8 µm, respectively. Experimental data revealed distinct variations in optical properties, including absorption, transmittance, band gap, and forbidden band gap, influenced by material and film fabrication process. These results show that the optical performance of PBO films can be guided by controlled synthesis and fabrication parameters, making them promising candidates for optoelectronic and sensor applications. © 2025 Elsevier B.V., All rights reserved.