Photoluminescence, Optical, and Electrical Properties of Bis(8-Hydroxyquinoline) Zinc and Tris-(8-Hydroxyquinoline) Aluminum Organometallics and Their Films

• Published in: Journal of electronic materials Vol. 53; no. 1; pp. 338 - 346
• Main Authors: Ahmad, Ahmad A., Aljarrah, Ihsan A., Al-Bataineh, Qais M., Ababneh, Riad, Telfah, Ahmad
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.01.2024; Springer Nature B.V
• Subjects: Aluminum; Characterization and Evaluation of Materials; Charge transfer; Chemistry and Materials Science; Diffraction patterns; Electrical properties; Electrical resistivity; Electronics and Microelectronics; Fourier transforms; Hydroxyquinoline; Infrared spectroscopy; Instrumentation; Materials Science; Optical and Electronic Materials; Optical properties; Organometallic compounds; Original Research Article; Photoluminescence; Polymethyl methacrylate; Solid State Physics; Spectrum analysis; Zinc; poly(methyl methacrylate) (PMMA); Organometallics; tris-(8-hydroxyquinoline) aluminum (AlQ; photoluminescence emission; ); intra-ligand charge-transfer (ILCT); bis(8-hydroxyquinoline) zinc (ZnQ
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-023-10788-x

Bis(8-hydroxyquinoline) zinc ( ZnQ 2 ) and tris-(8-hydroxyquinoline) aluminum ( AlQ 3 ) organometallics have been synthesized and incorporated into poly(methyl methacrylate) (PMMA) films for potential use in green-emitting OLED applications. The ZnQ 2 and AlQ 3 organometallics were prepared using an acid–base co-precipitation technique. Fourier-transform infrared spectroscopy and x-ray diffraction patterns were utilized to confirm the formation of ZnQ 2 , AlQ 3 , and ZnQ 2 –AlQ 3 compounds. UV–Vis spectroscopy analysis revealed that PMMA / ZnQ 2 , PMMA / AlQ 3 , and PMMA/(ZnQ 2 –AlQ 3 ) composite solutions exhibited two primary transition bands in the range of approximately 330 nm and 380 nm, corresponding to the π – π * and n – π * transition bands, respectively. The average electrical conductivity of the PMMA / ZnQ 2 composite film was measured as 1.19 μ S/cm, while the PMMA / AlQ 3 composite film displayed a conductivity of 1.56 μ S/cm, indicating that the intra-ligand charge-transfer of electrons in AlQ 3 was higher than that in Znq_2. Additionally, photoluminescence (PL) emission peaks for the PMMA / ZnQ 2 , PMMA / AlQ 3 , and PMMA/(ZnQ 2 –AlQ 3 ) composite solutions were observed at wavelengths of 522 nm, 505 nm, and 509 nm, respectively, confirming their potential suitability for use in green-emitting OLEDs.