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Öğe Effect of doping concentration on the structural and optical properties of nanostructured Cu-doped Mn3O4 films obtained by SILAR technique(Springer Verlag, 2018) Bayram O.; Guney H.; Ertargin M.E.; Igman E.; Simsek O.In this study, the effect of Cu doping on the optical, structural and wettability properties of the nanostructured Cu-doped Mn3O4 (CMO) thin films obtained by using successive ionic layer adsorption and reaction technique was systematically investigated. The optical, morphological, structural and wettability properties of the nanostructured CMO films were determined using scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–Vis spectroscopy, and water contact angle (WCA) measurements. There were significant differences in the crystal structure of the nanostructured CMO thin films. The Cu doping disrupted this structure of pure (undoped) Mn3O4 films and caused the formation of the porous structure. Optical properties such as extinction coefficient, refractive index, and dielectric constants and optical band gap, were determined for nanostructured CMO films. Compared with pure films, the band gap of Cu-doped films decreased from 2.06 to 1.71 eV with increasing Cu concentration. The dielectric constants of the films showed that the nanostructured CMO films have a transparent structure. At 300 nm wavelength, the dielectric constants of pure Mn3O4 films were 2.22 while the calculated dielectric constants at increasing doping concentrations were 3.55, 2.41 and 2.25. It was also found from the WCA measurements that the thin films were hydrophilic in character and the WCA values for the nanostructured CMO thin films were measured as 24, 29 and 40 of degree. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.Öğe Effect of the number of cycles on the optical and structural properties of Mn3O4 nanostructures obtained by SILAR technique(Springer New York LLC, 2018) Bayram O.; Simsek O.; Guney H.; Igman E.; Murat Ozer M.In this study, nanostructured Mn3O4 (manganese oxide) thin films were successfully obtained by successive ionic layer adsorption and reaction (SILAR) method on the soda lime glass substrates using Manganese Nitrate (Mn(NO3)2) and Ammonium hydroxide (NH4(OH)) as cationic and anionic precursors respectively. Structural and morphological characterizations of the Mn3O4 films obtained at different cycles were determined using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The crystal structure of the thin films were also confirmed by RAMAN spectroscopy. Optical properties such as absorption, transmission, reflection, extinction coefficient and optical band gap of nanostructured Mn3O4 thin films were determined by UV–Vis spectroscopy. SEM images showed that the manganese oxide nanosheets formed uniformly on substrate surface. As the deposition cycles increased, nano-sheets structure deteriorated. The optical band gap of Mn3O4 thin films varied from 2.12 to 2.59 eV, depending on the increase in number of cycles. From contact angle measurements of thin films, it was determined that thin films had hydrophilic character. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.Öğe Investigation of structural, morphological and optical properties of Nickel-doped Zinc oxide thin films fabricated by co-sputtering(Springer New York LLC, 2019) Bayram O.; Sener E.; İgman E.; Simsek O.In this study, it was aimed to grow Nickel doped (0.0 at.%, 0.16 at.%, 0.20 at. % and 0.24 at. %) Zinc Oxide (NZO) thin films on quartz substrates using Magnetron Sputtering technique. NZO thin films were obtained at a temperature of 450 °C, a pressure of 480 m Torr and a deposition time of 30 min. Co-sputtering process for both Ni and ZnO target was performed using two separate power sources. The DC power of the Ni target material was 20, 30 and 40 W, respectively while the radio frequency (RF) power of the Zinc oxide (ZnO) target material was set to 150 W. Using XRD analysis, thin films were found to have polycrystalline morphology, and the average crystallite size changed significantly depending on the increased Ni doping level. The optical Transmittance of the thin films was greater than 90% in the visible region (550 nm), and this value tends to decrease slightly by Ni doping. The optical band gap (E g ) firstly decreased and then slightly increased with the Nickel doping ratio and these values were found to be 3.23 eV, 3.11 eV and 3.15 eV, respectively, with increase of Ni doping. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.Öğe Investigation of the effect of RF energy on optical, morphological, chemical and antibacterial properties of PolyTerpenol thin films obtained by RF-PECVD technique(Springer New York LLC, 2018) Bayram O.; Simsek O.In this study, it was aimed to obtain PolyTerpenol thin films by radio frequency plasma enhanced chemical vapor deposition technique using Terpinen-4-ol essential oil, which is organic compounds. The surface morphology and chemical properties of polymer thin films were investigated by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy. AFM analyzes of PolyTerpenol thin films revealed that the thin films are homogeneous, smooth and nonporous. The optical properties of the thin films were determined using UV–Vis spectrophotometer. When optical band gaps of thin films were examined, it was found that this value varied from 3.83 to 3.20 eV. The extinction coefficients of the obtained thin films according to the increasing RF energy were calculated as 0.0011, 0.0060, 0.0085 and 0.0150, respectively, at a wavelength of 320 nm. In addition, antibacterial effects of these thin films against Escherichia Coli (E.Coli) bacteria were also investigated. The PolyTerpenol thin films were found to have high antibacterial activity against E. Coli bacteria. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.Öğe A nondestructive testing technique: Nail penetration test(2012) Selcuk L.; Gökce H.S.; Kayabali K.; Simsek O.This study presents a practical nondestructive testing (NDT) method: the nail penetration test (NPT). The major tools of the test technique are a gas nailer with 130 J (95.88 ft-lbf) power, concrete nails, and a gas nailer cell. The study covers three different limestone aggregate types. Six concrete mixtures were prepared from each aggregate type. Five nail shots were performed on each concrete mixture (or grade) and the average value was obtained. The average nail penetration depths were correlated with the compressive strength of concrete. Other NDT techniques, such as the Schmidt rebound hammer (SRH), ultrasonic pulse velocity (UPV), and Windsor probe (WP), were also applied to concrete samples. The measured compressive strength values were compared with those obtained from the empirical relationships using the data from the NPT, SRH, UPV, and WP. It was found that the reliability of the NPT to estimate the compressive strength of concrete is very high. The tool employed in the investigation covers a relatively wide range of compressive strength of concrete. This testing tool is proposed to estimate the compressive strength of in-place concrete. © 2012, American Concrete Institute.Öğe The role of cobalt doping on the optical and structural properties of Mn 3 O 4 nanostructured thin films obtained by SILAR technique(Academic Press, 2019) Özkan, Bayram; İgman E.; Guney H.; Simsek O.Cobalt doped manganese oxide thin films (Mn 3 O 4 :Co) were successfully deposited on soda lime glass substrates using SILAR technique. Mn 3 O 4 :Co thin films were characterized using XRD, SEM, Uv–VIS and Raman spectroscopy. The XRD spectra showed that thin films had substantially Hausmannite crystal structure. The preferential orientation of the pure and 0.5 at.% Co doped manganese oxide thin films (Mn 3 O 4 ) was (002), but with increasing Co doping, it was detected that this preferential orientation shift towards the (211) plane. The absorbance, transmittance and optical band gap of the Mn 3 O 4 :Co thin films were determined using Uv–Vis spectroscopy and these properties of the thin films differed considerably due to cobalt doping. The optical band gap of pure Mn 3 O 4 thin films was 2.00 eV, but on the other hand, due to the Co doping this value increased before and then decreased slightly. Optical transmittance of Mn 3 O 4 :Co films increased from 60% to 72% with the effect of Co doping. A1g mode, which is the characteristic vibration peak of Mn 3 O 4 films, was confirmed for pure and doped Mn 3 O 4 thin films at a wavelength of 658 nm. © 2019 Elsevier LtdÖğe A study on the optical, chemical and dielectric properties of PPCIN thin films derived from essential oil compounds using RF plasma polymerisation technique(Elsevier Ltd, 2018) Bayram O.; Simsek O.Polymer-based nanostructured films were produced on various substrates using Radio Frequency (RF) plasma polymerization technique from Cinnamaldehyde monomer which is an organic compound. To fabricate polymer thin film, the pressure, the deposition time and RF power were set to 480 mTorr, 30 min and 15, 20 and 30 W, respectively. The effect of RF power on the optical, morphological and chemical properties of thin films were investigated. The optical, morphological and chemical properties were determined by UV–Vis spectroscopy, Atomic Force Microscopy (AFM) and FTIR spectroscopy, respectively. The average surface roughness of thin films was detected as 5.7 nm, 3.9 nm and 11.7 nm using AFM depending on the increase in RF power. Using FTIR spectroscopy, the chemical structure of the polymer thin films was compared with that of the monomer material, and it was found that the majority of the functional groups belonging to the monomers also appeared in the thin films. Optical band gap of thin films increased with RF power and these values were determined as 2.83 eV, 3.05 eV and 2.98 eV, respectively. The extinction coefficients and refractive indices of the thin films were measured at 500 nm between 0.00183–0.00522 and 2.40–2.78, respectively. © 2018 Elsevier LtdÖğe Synthesis and characterization of Zn-doped Mn3O4 thin films using successive ionic layer adsorption and reaction technique: Its structural, optical and wettability properties(Springer New York LLC, 2018) Bayram O.; Ertargin M.E.; Igman E.; Guney H.; Simsek O.In this study, it is aimed to obtain Zn doped Mn3O4 (manganese oxide) nanostructured thin films on the soda lime glass substrates by successive ionic layer adsorption and reaction technique. The tetragonal crystal structure of the all thin films was detected using XRD spectroscopy. The average crystallite size of undoped Mn3O4 thin films was calculated to be 29 nm and for Zn-doped thin films, this value decreased to 23 nm with increasing Zn concentration. Characteristic peaks for thin films were also confirmed by RAMAN spectroscopy. The morphological structures of zinc-doped manganese oxide nano-sheets thin films were revealed by SEM. Using UV–Vis spectroscopy, it was found that the optical band gap of Mn3O4 thin films decreased from 2.05 to 1.73 eV with Zn doping. It has also been understood from the wettability analyzes of thin films that all thin films have a hydrophilic character. From all these analyzes, it is thought that the Zn doped Mn3O4 thin films have the potential to be used in supercapacitor applications. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.
