WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Synthesis, Characterization, Crystal Structure, Electrochemical and Photoluminescence Properties, Dft and Molecular Docking Studies, and Antimicrobial Activities of Two Mononuclear Nickel (II) Complexes With Pyrazole-Derived Ligands(Elsevier, 2025) Amin, Mina A.; Diker, Halide; Diker, Halide; Varlıklı, Canan; Sahin, Onur; Varlikli, Canan; Soliman, Ahmed A.; 01. Izmir Institute of Technology; 04.04. Department of Photonics; 04. Faculty of ScienceTwo octahedral nickel complexes; [Ni(fdtp)2(DMF)2] (1) and [Ni(dcdtp)2(DMF)2] (2), based on 4-((3-fluorophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol (fdtp) and 4-((2,4-dichlorophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol (dcdtp) were synthesized. The complexes were characterized spectroscopically (FTIR, UV-Vis, Photoluminescence), Mass spectrometry, elemental analyses, electrochemically, thermally, and through Single-crystal X-ray investigations. The formation of the complexes was confirmed by the existence of Ni-O and Ni-N vibrations at bonds were observed as weak bands at 526-497 and 470-438 cm-1. According to the thermogravimetric analyses, the complexes were thermally stable and had relatively high activation energies (585.81 and 730.07 kJ mol-1 for 1, and 2, respectively). Cyclic voltammograms showed that the anodic potential region of 1 and 2 exhibited two irreversible oxidation peaks at 1.34 V &1.55 V and 1.41 V & 1.63 V, respectively, attributed to metal-localized oxidation. The complexes showed enhanced antibacterial activities compared to free ligands and comparable to the standard. The inhibition zones exhibited via 1 were about 21.7, 19.3, and 26.7 mm versus Escherichia coli (E. coli), Staphylococcus aureus (S. Aureus), and Bacillus Subtits (B. Subtits), respectively. Docking studies supported the antibacterial investigations; the binding energies of the complexes were -8.81 and -9.69 kcal/mol for 1 and 2 respectively, against E. coli (PDB ID: 6F86).Article Citation - WoS: 2Citation - Scopus: 2New Copper and Cobalt Complexes Based on a Fluorinated Pyrazole Derivative, Synthesis, Characterization and Antibacterial Activity(Wiley, 2025) Amin, Mina A.; Diker, Halide; Diker, Halide; Varlıklı, Canan; Sahin, Onur; Varlikli, Canan; Soliman, Ahmed A.; 01. Izmir Institute of Technology; 04.04. Department of Photonics; 04. Faculty of ScienceTwo copper and cobalt complexes based on 3-(trifluoromethyl)-4-((3-(trifluoromethyl)phenyl)diazenyl)-1H-pyrazol-5-ol (Httdp) have been prepared and characterized using different physicochemical techniques. The crystal structure of the copper complex has been proven to be a square pyramidal, and the cobalt complex has an octahedral structure. DFT calculations of the complexes were performed, and the energy gaps between the HOMO-LUMO of the complexes (-3.38676 to -3.18138 eV) and the Cu (II) complex reflect a higher relative stability compared with Httdp and the Co (II) complex. The antibacterial activities of the two complexes were evaluated. The Co (II) complex demonstrated the highest antibacterial activity against various bacteria compared with Httdp and the Cu (II) complex. The mean inhibition zones exhibited by the Co (II) complex showed the highest activities toward the Gram-negative bacterial strains with mean inhibition zones of 30.3 +/- 0.6 (Staphylococcus aureus) and 25.7 +/- 0.6 (Bacillus subtilis) mm. Docking studies were carried out using S. aureus tyrosyl-tRNA synthetase (PDB ID: 1JIJ) to assess the antimicrobial activities, proving that the complexes were efficient for the protein.Article Improving the Device Stability by Controlling the Morphology of Quantum Dot Emissive Layer Via a Coating Process in Blue Qleds(Wiley-v C H verlag Gmbh, 2024) Özçelik, Serdar; Varlıklı, Canan; Diker, Halide; Ozcelik, Serdar; Varlikli, Canan; 01. Izmir Institute of Technology; 04.01. Department of Chemistry; 04.04. Department of Photonics; 04. Faculty of ScienceBlue light-emitting CdSe@ZnS/ZnS quantum dot (QD) nanoparticles (NPs) were synthesized and their photophysical properties in both solution and film phases were investigated. The morphological properties of films prepared by different coating methods i. e. single layer coating from low to high concentrations of QD solutions and layer-by-layer (multilayer) coating within constant low QD solution concentration, were also examined in detail. Varying the concentration (1-10 mg/mL) and the number of layers (from 1-16) did not essentially affect the photophysical properties of QD films, although it resulted in a direct increment in QD film thickness. The concentration and layer-dependent films were used as an emissive layer (EML) in QD light-emitting diodes (QLEDs). Although the "6 mg/ml(-1) Layer" QD EML-based device exhibited relatively high device efficiency compared to the "1 mg/ml(-10) Layers" based one at working voltage region, it had similar to 2-fold higher efficiency roll-off at high voltage region. The performance differences for both devices with the same QD EML thickness were attributed to the morphological variations for the QD layer in terms of surface roughness, void density, aggregates/clusters, and trap sites that were directly related to the charge injection balance and Auger recombination.Article Citation - WoS: 1Improving the Stability of Ink-Jet Printed Red Qleds by Optimizing the Device Fabrication Process(Eurasia Acad Publ Group (eapg), 2024) Varlıklı, Canan; Özçelik, Serdar; Diker, Halide; Varlikli, Canan; 01. Izmir Institute of Technology; 04.01. Department of Chemistry; 04.04. Department of Photonics; 04. Faculty of ScienceRed-light emitting Cadmium Sulfide 0.8 Selenide 0.2 /Zinc Sulfide (CdS (0.8) Se (0.2) /ZnS) based quantum dots (QDs) were synthesized by hot injection method and utilized as the emissive layer in the quantum dot light emitting diode (QLED) with the device structure of Indium Tin Oxide/Poly(3,4-ethylenedioxythiophene): Polystyrene Sulfonate / Polyvinylcarbazole(or Poly(N,N '-bis-4-butylphenyl-N,N '-bisphenyl)benzidin) /QD/ZincOxide/LithiumFluoride/ Aluminum [ ITO/ PEDOT: PSS/ PVK(or p-TPD )/QD/ZnO/LiF/Al]. QD inks were formulated and prepared octane: decane; (1/1, v/v) solvent system and mixed with the nonionic surfactant, TritonX-100, to make the QD inks inkjet printable. In addition to the inkjet printing technique, spin coating was also employed to form the QD emissive layer for comparing device performance. Compared to the p-TPD-based QLED device, the PVK-based device fabricated via spin coating exhibited similar to 6 -fold higher performance in terms of luminance and efficiency values. In the case of using the ink -jet printer, similar to 2 -fold higher maximum luminance value and slightly lower external quantum efficiency at the lower current density region were obtained in the p-TPD-based device. Furthermore, compared to the PVK layer, the p-TPD layer provided higher device stability regardless of the coating method the higher current density regions. We suggest that the coating method applied and the choice of hole transport layer (HTL) materials may control the device parameters.