Para-Phenylenediamine Schiff Base: Highly Fluorescent Photostable Solid-State Organic Dye
Photonics Research 2024
Hani Barhum, Mohammad Attrash, Inga Brice, V. Vjacheslav Kim, Cormac McDonnell, Mariam Amer, Madhat Matar, Jānis Alnis, Toms Salgals, Ibrahim Yehia, Vjačeslavs Bobrovs, Rashid A. Ganeev

Schiff bases derived from the condensation of primary amines with aldehydes, such as para-phenylenediamine with salicylaldehyde, exhibit unique optical and structural properties ideal for photonic applications. This study synthesizes such a Schiff base, revealing its properties through detailed 1HNMR, FTIR, and XRD characterizations. The compound forms a robust π-conjugated structure, showing a fluorescence emission peak at 560 nm and significant absorbance at 380 nm. A spin-coated laser cavity displayed a critical lasing threshold at 1 MW · cm−2, which could be optimized down to 0.6 kW · cm−2. Moreover, the compounds’ acceptor-donor-acceptor configuration raised outstanding nonlinear optical properties, including a substantial two-photon absorption cross-section of 2 × 10−11 cm . W−1 · GM, enhancing its utility in high-resolution two-photon imaging and advanced photonic applications. Other nonlinear optical characteristics determined during these studies are the saturable absorption-induced nonlinear absorption coefficient (−2 × 10−11 cm . W−1), saturation intensity (2.5 × 1011 W · cm−2), and Kerr-induced nonlinear refractive index (5 × 10−16 cm2 . W−1). The combined linear and nonlinear optical properties, supported by sustained emission and minimal photobleaching under intense re-excitation, establish the para-phenylenediamine Schiff base and derivatives as promising materials for high-brightness, photostable organic light emitters, and solid-state lasers


Keywords
Laser excitation; Luminance; Optical depth; Optical Kerr effect; Photobleaching; Refractive index; Two photon processes
DOI
10.1364/PRJ.531643
Hyperlink
https://opg.optica.org/prj/fulltext.cfm?uri=prj-12-11-2639&id=562041

Barhum, H., Attrash, M., Brice, I., Kim, V., McDonnell, C., Amer, M., Matar, M., Alnis, J., Salgals, T., Yehia, I., Bobrovs, V., Ganeev, R. Para-Phenylenediamine Schiff Base: Highly Fluorescent Photostable Solid-State Organic Dye. Photonics Research, 2024, Vol. 12, No. 11, pp.2639-2650. ISSN 2327-9125. Available from: doi:10.1364/PRJ.531643

Publication language
English (en)
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