Tailoring the optical properties of dye–polymer composite films based on polyvinyl alcohol doped with phenol red toward flexible optoelectronic applications

Abstract

The composite films of polyvinyl alcohol (PVA) incorporating varying concentrations of phenol red (PR) dye were fabricated using the solution casting method. Structural characteristics of the prepared films were explored through XRD and FTIR spectroscopy analyses. The inclusion of PR dye within the PVA matrix induced cross-linking, enhancing the amorphous nature of the doped PVA samples, as evidenced by XRD patterns. In the presence of PR dopants, the FTIR peaks for PVA exhibited altered intensities and increased width, indicating physical interactions between the functional groups of PVA and PR dopants. The impact of PR additives on the optical properties of PVA was investigated across the spectral range of 190-2500 nm. The PVA/phenol red composite demonstrated enhanced UV blocking in the 190-400 nm wavelength range, rendering it suitable for applications such as UV notch filters, including laser blocking filters. The indirect and direct optical band-gaps of PVA polymer films were reduced from 5.20 eV and 5.78 eV to 4.30 eV and 5.28 eV, respectively, with an increase in the PR filling ratio from 0 wt% to 1.8 wt%. The dispersion region of the refractive index was analyzed using the single oscillator model (Wemple-DiDomenico). Calculation and discussion of values such as dispersion and oscillation energies (Ed and Eo), permittivity at infinite frequency (ε∞), and lattice contribution to the dielectric function (εL) of PVA/PR composite films were conducted. These advancements position PVA/PR composite films for potential applications in flexible optoelectronic devices, including light-emitting diodes and photodetectors.

DFT Study of the Influence of Cationic and Anionic Fragments on the Linear Optical Properties, First Hyperpolarizability, and Two-Photon Absorption of Benzoxazole Derivatives: A Perspective for OLEDs and Solar Cells Applications

“…The study of linear optical properties, such as absorption and fluorescence, is fundamental due to its numerous scientific and technological applications (Abbas et al, 2024;Badi et al, 2023). In engineering, these phenomena are essential for the fabrication of advanced optical devices, such as OLEDs (Al-Muntaser et al, 2024;Nagata et al, 2024), lasers, field-effect transistors, and organic photovoltaics (Gul et al, 2023). Additionally, they have applications in biology (Latha et al, 2014), medicine (Finger et al, 2023), biotechnology (Mary et al, 2021), and materials science (Morgan & Jacobs, 2020), facilitating the characterization and optimization of biological samples and the development of new materials, such as fluorescent compounds for biomarkers (Schepici et al, 2020), photodynamic therapy (Li et al, 2020), and pharmacology (Velasquez et al, 2023), enabling advances in the detection and treatment of diseases such as cancer (Abramczyk et al, 2020) and cardiovascular problems (Liu et al, 2022).…”