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Öğe A comparative study on cobalt and aluminum as a dual doping element for CdO films(ELSEVIER SCI LTD, 2019) Cavusoglu, H.; Aydin, R.; Sahin, B.In the present study, we have delineated the synthesis of transparent conductive un-doped, Co doped (Co0.01Cd0.99 O) and Co:Al dual-doped CdO films [(Al-m,Co0.01Cd0.99-m) (m: 0.005, 0.01 and 0.02, respectively)] by using facile successive ionic layer adsorption and reaction (SILAR) method at room temperature. Scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX), X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) and ultraviolet-visible (UV-Vis) spectroscopic measurements had been executed to reveal the influence of Co and Al dopants on the morphological, crystallinity and optical characteristics of CdO films. The effect of Co doping and Co:Al dual doping on the surface morphology of CdO films was identified through SEM analysis. The EDX analysis results confirmed the presence of Co2+ and Al3+ dopant ions in the CdO lattices. The XRD measurements revealed that all of the SILAR-grown CdO films were polycrystalline with a cubic structure and exhibited (111) and (200) preferred orientations. The presence of chemical bonding was verified by FT-IR spectroscopic investigation. Furthermore, the optical band gap (E-g) values of the all deposited films were evaluated from UV-Vis spectrophotometric data. The ES values of all the films were remarkably widened in proportion to the Al doping from 1.92 eV to 3.05 eV. The investigations have shown that mono doping and dual doping have a substantial impact on the physical properties of SILAR-grown CdO films.Öğe Complexing agent triethanolamine mediated synthesis of nanocrystalline CuO thin films at room temperature via SILAR technique(ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2019) Cavusoglu, H.; Aydin, R.In the present work, nanostructured cupric oxide (CuO) thin films have been successfully deposited on glass substrates by successive ionic layer adsorption and reaction (SILAR) technique at room temperature. The influence of complexing agent as triethanolamine (TEA) on the structural, morphological, optical and electrical characteristics of nanocrystalline CuO thin films have been examined in detail. Structural studies confirm that all the films were polycrystalline nature having a monoclinic crystalline form and displayed ((1) over bar 11) and (111) preferential orientations. The estimated crystallite values ranged from 17.47 to 19.95 nm. The surface morphology of CuO thin films was examined through scanning electron microscopy and materials microscope studies. Surface studies revealed that homogeneously distributed CuO nanostructures on the film surfaces. The optical studies showed that band gap energy values of the CuO thin films were increased from 1.33 to 2.00 eV as a function of increasing TEA concentration. Meanwhile, the average transmittance of all the films had increased from 2.5 to 42.5% with the increasing TEA concentration. FTIR studies identified the formation of single phase CuO and chemical bonding of the complexing agent. The resistivity value of CuO thin film synthesized without TEA was 3.74 x 10(5) Omega cm and the resistivity consequently increased to 509 x 10(5) Omega cm with TEA concentration of 1.O M%. A high figure of merit (786 x 10(-12) Omega(-1)) was obtained for complexing agent concentration of 0.25 M%.Öğe Density functional theory - electron paramagnetic resonance study of gamma-irradiated single crystal of amphi-chloroglyoxime(TAYLOR & FRANCIS LTD, 2009) Turkkan, E.; Dereli, O.; Tasdemir, H. U.; Cavusoglu, H.The density functional theory was studied to examine the suggested type of model radicals RI, RII and RIII that have been formed upon gamma-irradiation of single crystals of amphi-chloroglyoxime (ACG). RI, RII and RIII type model radicals were obtained by abstraction of Cl and H atoms from ACG. The possible conformations of these model radicals were obtained using the semi-empirical Austin Model 1 method. Subsequently, hyperfine coupling constants and atomic spin density calculations of these conformations were performed using the Becke-3-Lee-Yang-Parr functional in combination with a split-valence Gaussian basis set. Theoretically calculated values were compared with the experimental values. Calculated isotropic and anisotropic hyperfine coupling constant values of conformations of model radical RII were in good agreement with experimental values. However, the agreement was rather poor in the case of the model radicals RI and RIII. Thus, the findings from the present study clearly suggest that the experimentally observed radical should be the model radical RII.Öğe Evaluation of the adjuvant effect of gold nanocages in vitro(WILEY-BLACKWELL, 2016) Yavuz, E.; Sakalak, H.; Cavusoglu, H.; Uyar, P.; Yavuz, M. S.; Bagriacik, E. U.[Abstract not Available]Öğe Evaluation of the adjuvant effect of gold nanocages in vitro -- 2(WILEY-BLACKWELL, 2016) Yavuz, E.; Sakalak, H.; Cavusoglu, H.; Uyar, P.; Yavuz, M. S.; Bagriacik, E. U.[Abstract not Available]Öğe A theoretical study about factors affecting conformational stabiltiy order of glyoxime(SILA SCIENCE, 2011) Dereli, O.; Cavusoglu, H.; Turkkan, E.; Ozmen, A.; Ilik, A.In this study, stable conformers and the effects determining conformational stability of the glyoxime (GO) molecule are inspected. Semiemprical PM3 method is used for conformer distribution. Geometry optimizations are performed by MP2/6-311++G(d,p) level of theory. We obtained twenty stable conformers for the title compound; however conformer 1 is (approximately 17 kcal/mol) more stable than conformer 20. Calculated geometry parameters for the most stable conformer are consistent with experimental results. Long range electrostatic, conjugation, and hydrogen bonding effects are found responsible for stability order of GO. Four conformers which can be determined experimentally are isolated theoretically. Thermodynamic and geometrical parameters of these isomers are given first time in this study. Calculated relative energies of these conformers are very close to each other. For this reason, isolation of these conformers is very difficult for experimentalists. The chemical reactivities of GO conformers were investigated by HOMO-LUMO energy gaps.Öğe Transition metal Mn/Cu co-doped CdO transparent conductive films: Effect on structural, morphological and optical characteristics(ELSEVIER SCIENCE SA, 2019) Aydin, R.; Cavusoglu, H.; Sahin, B.The transparent conducting un-doped, Cd-0.99 Mna(0.01)O (Mn: 1.0%) and Mn/Cu co-doped CdO [(CuxMn0.01Cd0.99-x) (x: 0.005, 0.01 and 0.02 respectively)] films were prepared by successive ionic layer adsorption and reaction (SILAR) technique on soda lime glass substrates. The effect of Mn and Cu-dopant on structural, morphological and optical characteristics of the CdO films was analyzed by XRD, SEM, UV-Visible spectrophotometer and FT-IR spectroscopy. The XRD studies showed that the all-SILAR prepared films were polycrystalline and had preferential growth along the (111) directions. SEM analysis revealed that the Mn doping and Mn/Cu co-doping significantly influenced the surface morphologies of the CdO films. The EDX results confirmed that the dopant ions were incorporated properly into the CdO lattices. The optical band gap energy values of the all deposited films were determined by extrapolation method and observed to be in the range of 2.08-2.38 eV. Optical analysis results disclosed that doping alters the band gap facilitating the potential of transparent conductive films to be exploited in optoelectronic devices. Furthermore, FT-IR was used to confirm the existence of metal-doped CdO. The investigations showed that co-doping significantly affects the physical properties of SILAR-grown CdO films. (C) 2019 Elsevier B.V. All rights reserved.
