Effect of growth temperatures on the structural and optical properties of bulk tris-(8-hydroxyquinoline) aluminium (III)

• Published in: Applied physics. A, Materials science & processing Vol. 130; no. 5
• Main Authors: Debsharma, Mrinmoy, Pramanik, Tanay, Pramanik, Goutam, Maity, Amit Ranjan, Jain, Alok, Mukherjee, Rupam
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2024; Springer Nature B.V
• Subjects: Aluminum oxide; Annealing; Blue shift; Characterization and Evaluation of Materials; Condensed Matter Physics; Diffraction patterns; Doppler effect; Fourier transforms; Hydroxyquinoline; Infrared spectra; Machines; Manufacturing; Nanotechnology; Optical and Electronic Materials; Optical properties; Physics; Physics and Astronomy; Processes; Red shift; Spectrum analysis; Surfaces and Interfaces; Temperature dependence; Thin Films; Hydrolysis; Non fluorescent; Optoelectronic; Annealing; Quenching
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-024-07461-3

Bulk samples of Tris (8-hydroxyquinoline) aluminium (Alq 3 ) were prepared using wet synthesis method followed by annealing at 50 °C, 100 °C, 150 °C and 200 °C for 2 h. X ray diffraction pattern showed the formation of Alq 3 crystal which is constituted of Al atom, anions of 8-hydroxyquinoline (8-Hq) and porous Al 2 O 3 –Al(OH) 3 . structure. The spectra of FTIR (Fourier-transform infrared) reveals that annealing Alq 3 at 50 °C reduces the C=C peak to negligible but reappears when annealed at 150 °C. FESEM on as-prepared Alq 3 shows hexagonal rod shaped stacked structures which on annealing at 50 °C changes to tetragonal agglomerated grains along with appearance of oval and circular shaped pores on it. From fluorescence spectroscopy it is found that the peak intensity changes non-monotonically with annealing temperatures followed by red shift and blue shift of peak maximum at 150 °C and 200 °C respectively. The temperature dependent change in the properties are mainly attributed to the onset of hydrolysis in Alq 3 and change in the electronic transition levels.