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Öğe Facile and Rapid Synthesis of Microwave Assisted Pd Nanoparticles as Non-Enzymatic Hydrogen Peroxide Sensor(ESG, 2017) Sahin, Ozlem; Kivrak, Hilal; Kivrak, Arif; Kazici, Hilal Celik; Alal, Orhan; Atbas, DilanCarbon supported Pd catalyst was prepared with microwave-assisted polyol method (M-Pd@C) and investigated sensing activity for non-enzymatic hydrogen peroxide (H2O2). Moreover, M-Pd@C and Pd@C catalyst which synthesized via polyol method (P-Pd@C) were compared to each other in terms of electrocatalytic activity. X-ray diffraction (XRD), X-ray photo electron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate structural and morphological properties of these catalysts. Furthermore, electrochemical measurements were performed via cyclic voltammetry (CV), chronoamperometry (CA) techniques. CV results exhibited that M-Pd/C catalyst showed perfect electrocatalytic activity in terms of reduction of H2O2. M-Pd/C catalyst showed a fast response of less than 7 s with a linear range of 5.0x10(-3)-11.0 mM and a relatively low detection limit of 1.2 mu M amperometric response. M-Pd/C catalyst exhibited great selectivity for detecting H2O2 in the existence of several hindering species such as uric acid and ascorbic acid.Öğe Facile and Rapid Synthesis of Microwave Assisted Pd Nanoparticles as Non-Enzymatic Hydrogen Peroxide Sensor (vol 12, pg 762, 2017)(ESG, 2018) Sahin, Ozlem; Kivrak, Hilal; Kivrak, Arif; Kazici, Hilal Celik; Alal, Orhan; Atbas, Dilan[Abstract not Available]Öğe Synthesis and solar-cell applications of novel furanyl-substituted anthracene derivatives(ELSEVIER SCIENCE BV, 2017) Kivrak, Arif; Er, Omer Faruk; Kivrak, Hilal; Topal, Yasemin; Kus, Mahmut; Camlisoy, YesimAt present, novel furanyl-substituted anthracene derivatives; namely 9,10-di(furan-2-yl)anthracene (DFA), 5,5'-(anthracene-9,10-diyl)bis(furan-2-carbaldehyde) (DAFA) and 2,2'-((5,5'-(anthracene-9,10-diyl)bis(furan-5,2-diyl))bis(methanylylidene))dimalononitrile (DCNFA) were designed and synthesized successfully by employing Stile Cross-Coupling, Vilsmeier-Haack and Knoevenagel condensation reactions, respectively. This methodology provides a practical new route for the synthesis of furanyl-substituted anthracene derivatives bearing strong electron-withdrawing groups. The electrochemical and electro-optical properties of these novel furanyl-substituted anthracene derivatives were also examined with strong acceptor-pi-donor-pi-acceptor interactions. Furthermore, Highest occupied molecular orbital (HOMO), Lowest Unoccupied molecular orbital (LUMO), and band gap (Eg) values were investigated by using spectroscopic methods. Electrochemical and electro-optical properties were calculated and compared to DFA, DAFA and DCNFA. Eg was found as 2.85, 2.71, and 2.33 eV, respectively. Consequently, Organic Solar Cells (OSC) were fabricated to investigate their solar cell performances. The strong electron withdrawing groups did not increase the solar cell performance of furanyl-anthracenes. Surprisingly, DFA was found to exhibit the best OSCs performance (Efficiency = 3.36). As a result, one could note that these novel furanyl-substituted anthracene derivatives are good candidate for the applications of the OSCs. Our results might help in the development of new materials with important electrochemical functions by giving the advantage of designing and further derivatization of new generation small organic molecules for photovoltaic device applications. (C) 2017 Elsevier B.V. All rights reserved.Öğe Synthesis of tetracyanoethylene-substituted ferrocene and its device properties(WILEY, 2018) Kivrak, Arif; Zobi, Cengiz; Torlak, Yasemin; Camlisoy, Yesim; Kus, Mahmut; Kivrak, HilalSmall organic molecules are promising candidates for cheaper, flexible and good-performance sources for organic solar cells (OSCs) due to their easy fabrication, low cost and slightly cheaper processing. However, the lower power conversion efficiency of OSCs is the main problem for their applications. Ferrocene structures could be the best candidates for the active layers of OSCs due to their unique properties such as thermal and chemical stability. The electrochemical, electro-optical and solar cell performances of 2,5-dicyano-3-ferrocenyl-4-ferrocenylethynylhexa-2,4-dienedinitrile (DiCN-Fc) structures were investigated. First, the electrochemical and electro-optical properties were examined for finding the highest occupied and lowest unoccupied molecular orbital values and bandgap of DiCN-Fc. The best photovoltaic performance was obtained with 7 wt% of DiCN-Fc loading, with a power conversion efficiency of about 4.27%. In the light of our investigations, ferrocenyl-substituted small organic molecules could contribute to the development of organic photovoltaic devices.Öğe Synthesis of thiophenyl-substituted unsymmetrical anthracene derivatives and investigation of their electrochemical and electrooptical properties(ELSEVIER SCIENCE BV, 2017) Kivrak, Arif; Calis, Hatice; Topal, Yasemin; Kivrak, Hilal; Kus, MahmutNovel thiophenyl-substituted anthracene derivatives (D-A)bearing a variety of electron-withdrawing groups were designed and synthesized for organic solar cells (OSCs). Their electrochemical and electro-optical properties were examined with strong donor-acceptor interaction. The electrochemical properties were examined by cyclic voltammetry (CV) measurements. These estimated values from CV measurements are in good agreement with the optical band gaps. HOMO, LUMO, and Eg values of designed organic materials were estimated. Furthermore, these new generation organic materials were fabricated to find their solar cell performances.