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    DFT analysis and electronic properties, and synthesis of tetra (9-phenyl-9H-xanthen-9-yl) oxy peripheral-substituted zinc phthalocyanine
    (Springer Int Publ Ag, 2020) Solgun, Derya Gungordu; Keskin, Mehmet Salih; Yildiko, Umit; Agirtas, Mehmet Salih
    The 4-((9-phenyl-9H-xanthene-9-yl) oxy) phthalonitrile compound was synthesized and characterized as starting material. Zinc phthalocyanine was obtained by reaction of 4-((9-phenyl-9H-xanthen-9-yl) oxy) phthalonitrile with Zn(CH3COO)(2). Novel compounds were characterized using mass spectra, UV-Vis spectroscopy, H-1-NMR, C-13 NMR, and infrared spectroscopy. The fluorescence, emission, excitation, and absorption spectra of the zinc phthalocyanine compound were studied in tetrahydrofuran (THF). The determination of these properties is very useful for photodynamic therapy applications. Also, zinc phthalocyanine (Zn-Pc) was optimized with the basic set of 6-311G and LanL2DZ of the Density functional theory (DFT). The energy band-gap HOMO-LUMO of the molecule was determined. Chemical indices were calculated using HOMO-LUMO energies. The electrophilic region and the nucleophilic region were defined from the molecular electrostatic potential (MESP) maps. Dipole moment components have been calculated and can be considered as potential candidates for the design of non-linear optical materials.
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    Öğe
    Hydrogen production performance and kinetic behavior from sodium borohydride hydrolysis with TiO2-supported Co-Mo-B catalyst
    (Springer Heidelberg, 2023) Keskin, Mehmet Salih; Agirtas, Mehmet Salih
    In the study, a new catalyst was designed and synthesized by chemical reduction and precipitation method by impregnating the Co-Mo-B catalyst with different support materials (TiO2, Al2O3, and CeO2) in order to obtain fast hydrogen from sodium boron hydride hydrolysis. According to the support material, their catalytic activities were observed as Co-Mo-B@TiO2 > Co-Mo-B@CeO2 > Co-Mo-B@Al2O3 > Co-Mo-B. Other experimental studies were continued with the Co-Mo-B@TiO2 catalyst, which exhibited the strongest catalytic activity. BET, XRD, SEM, and EDX analyses were performed with the analytical method and their characteristics were determined. For sodium boron hydride hydrolysis of the catalyst, firstly, the optimum (Co/Mo and Co-Mo@TiO2) ratios were determined. The optimal % NaOH and NaBH4 mass concentrations, the amount of catalyst, and the effect of temperature on the hydrogen production rate were investigated. It was observed that the reaction time was shortened and the hydrogen production rate increased at 30-50 & DEG;C temperature. Kinetic parameters were calculated accordingly. The reaction rate order was determined as 0.62 from the nth order. The activation energy from the Arrhenius equation was be calculated as 40.106 kJ/mol. Hydrogen production rate at 30 & DEG;C was found to be 19.968 mL/min & BULL;g & BULL;cat.
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    Potasyum Borhidrit Hidroliz Reaksiyonu İçin Ni-B-P Katalizörünün Kinetik Özellikleri
    (2020) Keskin, Mehmet Salih; Ağırtaş, Mehmet Salih; Baytar, Orhan; İzgi, Mehmet Sait; Şahin, Ömer
    Bu çalışmada potasyum bor hidrür hidrolizindeki hidrojen üretimi için yüksek performanslı Ni-B-P katalizörüsentezlenmiştir. Bilindiği üzere katalizörler kimya endüstrisinde gerçekleştirilen çoğu reaksiyonlarda kullanılırlar.Burada analitik yöntemle katalizörün, BET, XRD ve SEM analizleri yapılarak katalizörün karakteristik özellikleribelirlendi. Ayrıca Ni2P katalizörünün potasyum bor hidrolizi için; en iyi Ni/P oranı, optimum KOHkonsantrasyonu, KBH4 konsantrasyonu, katalizör miktarı ve kinetiksel parametreler için farklı sıcaklıklardakietkisi incelendi. Katalizörün hidrojen üretim hızının 665 mL/dak*g, en iyi Ni/P oranının 0.184 olarak belirlendi.Ayrıca reaksiyon hız mertebesi n- dereceden 0.25 olarak belirlendi, buna bağlı olarak ta arhenius eşitliğindenaktivasyon enerjisinin değeri 58,528 kJ/mol olarak bulunmuştur.
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    Preparation of Metal Complexes of 4,5-Dichlorphthalic Acid as Nanoscale and Electronic Properties
    (2020) Keskin, Mehmet Salih; Yıldıko, Ümit; Solğun, Derya Güngördü; Ağırtaş, Mehmet Salih
    Here phthalic acid metal complexes with acid function were synthesized. Fourie transform infrared spectroscopy (FT- IR), X-ray diffraction analysis (XRD), Scanning electron microscopy-Energy Dispersive Spectrometry (SEM+EDS) devices were used for structure analysis. The structural parameters of the copper and zinc complexes of 4,5-dichlorphthalic acid were determined by the LanL2DZ basis base set of B3LYP method. Electronic properties such as HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energies and molecular electrostatic potential (MEP) were obtained. Stability, charge delocalization of molecules resulting from hyperconjugative interactions were analyzed using natural bond orbital (NBO) analysis. The comparison of the theoretical and experimental FT-IR spectra of Zn and Cu-4,5-dichlorphthalic acid (DCPA) were made and R = 0.97204 for Cu and R = 0.97929 for Zn complex were found in linear fit studies. Two characterization results were found to be consistent.