Photonics / Fotonik
Permanent URI for this collectionhttps://hdl.handle.net/11147/2590
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Article Citation - WoS: 3Citation - Scopus: 4Soluble Cytotoxic Ruthenium(ii) Complexes With 2-Hydrazinopyridine(Pleiades Publishing, 2019) Soliman, A. A.; Attaby, F. A.; Alajrawy, O., I; Majeed, S. R.; Şahin, C.; Varlıklı, CananNew water soluble Ru(II) binary complex [Ru(C5H7N3)(X)(H2O)(2)] with 2-hydrazinopyridine and its ternary complexes with X = dichloride, oxalate, malonate or pyrophosphate ligands have been synthesized. The complexes have been characterized using elemental analyses, mass, IR, and UV-Vis. spectroscopies, cyclic voltammetry, magnetic susceptibility, and thermal analysis. The complexes are diamagnetic and the electronic spectral data showed that peaks are due to low spin octahedral Ru(II) complexes. The optimized structures of the complexes 1-4 indicate distorted octahedral geometry with bond angles around the ruthenium atom ranged from 80.44 degrees to 99.64 degrees. The values of the electronic energies (-635 to -1145 a.u.), the highest occupied molecular orbital energies (-0.181 to 0.073 a.u.) and lowest unoccupied molecular orbital energies (-0.056 to 0.167 a.u.) indicate the stability of the complexes. The complexes are polarized as indicated from the dipole moment values (9.39-14.27 Debye). The complexes have noticeable cytotoxicity with IC50 (mu M): 0.011-0.062 (HepG-2), 0.015-0.080 (MCF-7), 0.015-0.116 (HCT-116), and PC-3 (0.034-0.125).Article Citation - WoS: 31Citation - Scopus: 34Highly Efficient Supercapacitor Using Single-Walled Carbon Nanotube Electrodes and Ionic Liquid Incorporated Solid Gel Electrolyte(SAGE Publications, 2018) Siyahjani, Shirin; Öner, Saliha; Singh, Pramod K.; Varlıklı, CananGel polymer electrolyte (GPE) comprising a low viscosity ionic liquid, that is, 1-propyl-3-methyl imidazolium bis(trifluoromethyl sulfonyl)imide (PMI-TFSI, viscosity 38 cP at 20°C) and a polymer, that is, polyvinyl alcohol (PVA) have been prepared using solution cast technique and characterized by impedance spectroscopy, X-ray diffraction, differential scanning calorimetry, optical microscopy, and Fourier transform infrared spectroscopy. Blending PMI-TFSI with PVA matrix hindered the crystallinity of polymer matrix and presented remarkable enhancement in electrical conductivity with a conductivity maxima at 250 wt% PMI-TFSI. The prepared electric double-layer capacitor using single-walled carbon nanotube as symmetric electrodes and PVA:250 wt% PMI-TFSI as GPE presented a capacitance value of about 28 F g−Article Citation - WoS: 3Citation - Scopus: 3Monolayer Aste2: Stable Robust Metal in 2d, 1d and 0d(Wiley, 2018) Badalov, S. V.; Kandemir, Ali; Şahin, HasanThe structural, phononic, and electronic properties of the monolayer structures of AsTe2 are characterized by performing density functional theory (DFT) calculations. Total energy optimization and phonon calculations reveal that single layers of the 2H-AsTe2 and 1T-AsTe2 phases form dynamically stable crystal structures. Electronic structure analysis also shows that both 2H and 1T phases have nonmagnetic metallic character. It is also predicted that the metallic nature of the ultra-thin both 2H-AsTe2 and 1T-AsTe2 structures remain unchanged even under high biaxial strain values. For further examination of the dimensionality effect in the robust metallicity in 2D AsTe2 phases, electronic characteristics of 1D nanoribbons and 0D quantum dots are also investigated. It is found that independent from the dimension and crystallographic orientations 0D and 1D structures of 2H- and 1T-AsTe2 structures have metallic behavior. It is found that single layers of AsTe2 are quite promising materials for nanodevice applications owing to the robust metallic character.Article Citation - WoS: 12Citation - Scopus: 11Theoretical and Experimental Investigation of Conjugation of 1,6-Hexanedithiol on Mos2(IOP Publishing Ltd., 2018) Gül, Aytaç; Bacaksız, Cihan; Ünsal, Emre; Akbalı, Barış; Tomak, Aysel; Zareie, Hadi M.; Şahin, HasanWe report an experimental and theoretical investigation of conjugation of 1,6-Hexaneditihiol (HDT) on MoS2 which is prepared by mixing MoS2 structure and HDT molecules in proper solvent. Raman spectra and the calculated phonon bands reveal that the HDT molecules bind covalently to MoS2. Surface morphology of MoS2/HDT structure is changed upon conjugation of HDT on MoS2 and characterized by using Scanning Electron Microscope (SEM). Density Functional Theory (DFT) based calculations show that HOMO-LUMO band gap of HDT is altered after the conjugation and two-S binding (handle-like) configuration is energetically most favorable among three different structures. This study displays that the facile thiol functionalization process of MoS2 is promising strategy for obtaining solution processable MoS2.Conference Object Citation - WoS: 9Citation - Scopus: 11White Led Light Production Using Dibromoperylene Derivatives in Down Conversion of Energy(Canadian Science Publishing, 2018) Aksoy, Erkan; Demir, Nuriye; Varlıklı, CananPerylene derivatives of N,N′-bis(2,6-diisopropylphenyl)-1,6(7)-dibromoperylene-3,4,9,10-tetracarboxylic diimide (DBrPDI) and 1,7-dibromo perylene-3,4,9,10-tetracarboxylic acid butyl ester (DBrPTE) were synthesized, and their structural and optical characterizations were explored. Both DBrPDI and DBrPTE, which were utilized as wavelength converters on a GaN/InGaN based blue LED, were singlet sensitizers and had molar absorptivity constants around 104 Lmol-1cm-1. The blue LED that was used had Commission internationale de l'eclairage (CIE) coordinates of x, y = 0.13, 0.06; power and luminous efficiencies of 2.7 lm/W and 6.6 cd/A @5 mA, respectively. Because the fluorescence quantum yield of DBrPDI was much higher than that of DBrPTE, a meaningful white light efficiency was obtained with the diimide derivative. The use of DBrPDI resulted in white light with CIE coordinates of x, y = 0.34, 0.29 and luminous efficiency of 6.35 cd/A @5 mA, respectively. Using DBrPDI in a resin matrix resulted in more than three orders of magnitude increase in the luminous efficiency value (23.0 cd/A @5 mA) while the CIE coordinates remained the same. Whenever the applied current reached 20 mA, a CRI value of Ra = 90 was obtained.Article Citation - WoS: 14Citation - Scopus: 14Quantum-Transport Characteristics of a P–n Junction on Single-Layer Tis3(John Wiley and Sons Inc., 2016) İyikanat, Fadıl; Senger, Ramazan Tuğrul; Peeters, François M.; Şahin, HasanBy using density functional theory and non-equilibrium Green′s function-based methods, we investigated the electronic and transport properties of a TiS3 monolayer p–n junction. We constructed a lateral p–n junction on a TiS3 monolayer using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 p–n junction. In addition, the spin-dependent current–voltage characteristics of the constructed TiS3 p–n junction were analyzed. Important device characteristics were found, such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 p–n junction. These prominent conduction properties of the TiS3 p–n junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material.