Study on Relationship Between Fluorescence Properties and Structure of Substituted 8-Hydroxyquinoline Zinc Complexes

Abstract

Organic light-emitting diodes (OLEDs) produced from 8-hydroxyquinoline metal complexes play a vital role in modern electroluminescent devices. In this manuscript, a series of 8-hydroxyquinoline derivatives were synthesized by different methods and their corresponding zinc metal complexes were prepared. The UV and fluorescence properties of the complexes were measured aiming to understand the effect of substituents at the quinoline ring on the fluorescence properties of the complexes. When the C-5 of 8-hydroxyquinoline was replaced by halogen group, the fluorescence emission wavelengths had been red-shifted, at the same time, blue-shifted of fluorescence emission wavelength was observed when the C-5 position of 8-hydroxyquinoline was substituted by electron-withdrawing group. When the C-4 position of 8-hydroxyquinolie was substituted by methyl or the C-5 position was substituted by sulfonic acid group, the corresponding zinc complexes had higher fluorescence intensity than 8-hydroxyquinolie zinc.

On sombor indices of tetraphenylethylene, terpyridine rosettes and QSPR analysis on fluorescence properties of several aromatic hetero‐cyclic species

“…In this section we investigate QSPR of all six types of sombor indices using maximum excitation wavelengths and the maximum emission wavelengths as physical properties of above chemical structures. We take 22 aromatic hetero‐cyclic species taken from [16,27,28]. Table 4 contains fluorescence Properties (maximum excitation wavelengths and the maximum emission wavelengths ) of chemical structures presented in Figure 3.…”

“…Maximum emission wavelength represents the wavelength of light emitted by a molecule when it relaxes from an excited state to a lower energy state. It corresponds to the peak intensity in the fluorescence emission spectrum [16]. Aromatic heterocyclic species, which contain one or more heteroatoms (atoms other than carbon) within a ring structure, often exhibit interesting fluorescence properties.…”

Antibacterial activity of the micro and nanostructures of the optical material tris(8-hydroxyquinoline)aluminum and its application as an antimicrobial coating

“…These two PL peaks result from the ligands' electronic p-p* transitions. 35,36 The PL emission spectra of the samples, in the spectral range of 400-750 nm (l ex ¼ 380 nm), are shown in Fig. 5b; the spectra show a broadband peak centered at 495 nm.…”

“…5b; the spectra show a broadband peak centered at 495 nm. This peak results from the electronic p-p* transitions in the quinolinolate ligands, 35,36 in which the electrons predominantly at the phenoxide ring transit to the pyridyl ring. 37 The Alq 3 NP sample shows a signicantly lower intensity than that of the Alq 3 as rec sample.…”

A Multimodal Study on the Unique Sensing Behavior of a Guest@Metal‐Organic Framework Material for the Detection of Volatile Acetone

“…When subjected to UV radiation, the pristine ZnQ complex, where two 8‐hydroxyquinoline (8HQ) aromatic molecules are coordinated to a single Zn center, emits an intense yellow light, or if the molecules are isolated in solution, a green light. [ 20,21 ] The ZnQ@OX‐1 complex, however, exhibits an emission of blue light (480 nm), which, upon exposure to acetone, changes to a green emission (510 nm), as shown in Figure 1d. This shift in maximum emission wavelength is accompanied by quenching of emission intensity in the macroscopic scale, as the signal is decreased by one order of magnitude (Figure 1e).…”