Yazar "Yigit, M. Z." seçeneğine göre listele

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    Investigation of the Electrical Parameters of the Organic Diode Modified with 4-[(3-Methylphenyl)(phenyl)amino] Benzoic Acid
    (Electrochemical Soc Inc, 2016) Havare, A. Kemal; Can, M.; Yagmurcukardes, N.; Yigit, M. Z.; Aydin, H.; Okur, S.; Demic, S.; Icli, S.
    4-[(3-Methylphenyl)(phenyl)amino]benzoic acid (MPPBA) self-assembled monolayer (SAM) molecules as hole injection is formed on p and n type Si and on indium-tin oxide (ITO) electrodes to investigate the effect on the electrical parameters of hole only organic device. The hole mobility improvement of organic device was attributed to an intermediate energy level formed between hole transport materials (HTL) (N,N'-Bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine -NPB) and ITO when forming an ultrathin MPPBA layer, leading to increase of carrier mobility of the device. Space charge limited current (SCLC) technique is used to estimate the mobility of the NPB formed at the interface metal/organic Ohmic contact. The hole mobility of ITO/NPB/Al and ITO/MPPBA/NPB/Al devices were obtained as 1.80 x 10(-6) and 1.76 x 10(-3) cm(2)/Vs, at 1350 E (V/cm)(1/2) applied electric field, respectively. SAM modified devices has lower barrier height values. The electronic characteristic parameters of the ITO/(with or without MPPBA)/NPB/Al, Au/n-Si(or p-Si)/(with or without MPPBA)/Au contacts were calculated using current-voltage (I-V) measurements by Schottky type carrier injection. (C) The Author(s) 2016. Published by ECS.
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    Synthesis of two tri-arylamine derivatives as sensitizers in dye-sensitized solar cells: Electron injection studies and photovoltaic characterization
    (Elsevier Science Sa, 2014) Can, M.; Yigit, M. Z.; Seintis, K.; Karageorgopoulos, D.; Demic, S.; Icli, S.; Giannetas, V.; Fakis, M.; Stathatos, E.
    Two organic sensitizers with the structure donor-pi-acceptor, having tri-arylamine as electron donor, cyano-acetic acid as electron acceptor and a phenyl or thiophene ring as pi-bridge, are synthesized. The synthetic procedure, the photophysical and electrochemical properties of both dyes are described in detail. In particular, cyclic voltammetry and spectroscopic measurements were performed while the energy gap between highest occupied and lowest unoccupied molecular orbital for both dyes was calculated. Besides, electron injection dynamics on a series of titanium dioxide nanostructured films sensitized with the two dyes were investigated with time resolved fluorescence spectroscopy using femtosecond temporal resolution, while nanostructured alumina films were used as reference. The photovoltaic performances of both dyes in quasi-solid state dye sensitized solar cells were also investigated. A maximum overall conversion efficiency of 3.8% was monitored for two micrometer thin titanium dioxide films and quasi-solid state electrolyte. The performances of the solar cells are explained in terms of photophysical properties and electron injection dynamics of both dyes. (C) 2013 Elsevier B.V. All rights reserved.