Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2025Scopus SJRQ2Green synthesis of environmentally friendly Ag/AgCl nanoparticles for use as solid phase extraction materials
Kurnaz Yetim, Nurdan; Hasanoğlu Özkan, Elvan; Aslan, Naim; Koç, Mümin Mehmet; Nartop, Dilek; Özcan, Cemile
Green synthesis is a prominent procedure used to easily and environmentally friendly fabricate nanostructures and nanoparticles (NPs), without complex instrumentation, intricate procedures, and harmful chemicals. This study investigated the green synthesis of silver NPs (AgNPs), with Aronia melanocarpa fruit extract as the reducing agent. Following synthesis optimization, AgNPs were characterized using a range of analytical techniques, including UV–Vis, XRD, SEM-EDX, BET, and TEM analyses. Based on the characterization results, an Ag/AgCl hybrid structure was formed. The Ag/AgCl NPs obtained were utilized as adsorbents to remove Cd(II) and Pb(II) heavy metals. The experimental factors that were optimized included pH (5.5), sample volume (5 mL), eluent type and concentration (2 M HNO3), adsorbent amount (5 mg), and extraction time (30 min). Under optimized conditions, the limits of detection were determined to be 9.6 and 4.8 µg/L for Pb(II) and Cd(II), respectively. These limits were established within a concentration range of 50–3,000 µg/L.
AtıfScopus3WoS3OpenAlex3İncele
- Kitap BölümüYalnız künye2025DLC coatings for optical and optoelectronic applications
Koç, Mümin Mehmet; Aslan, Naim
Diamond-like carbon (DLC) materials, special amorphous forms of carbon, are quite stable and durable, therefore finding applications in different industries. It baffles people from both industrial and scientific communities where tribological, mechanical, chemical, optical, and optoelectronic properties were used for various applications. DLC films were used in different optical applications regarding their optical performance. Having outstanding shear and mechanical performance and high chemical inertness makes DLC thin films a suitable candidate for optical applications and devices that work under tough conditions. Thus, they were preferred in photovoltaic devices, monitors, cameras, lenses, medical devices, fiber optic cable technologies, and illumination technologies. Their absorption, emission, and transmission characteristics were also addressed in various optical applications and studies.
AtıfScopus4OpenAlex1İncele
- MakaleYalnız künye2024Scopus SJRQ2Sonochemical removal of Pb (II) ions from the water medium using Bi2S3 nanostructres
Kurnaz Yetim, Nurdan; Berberoğlu, Elif Aybike; Aslan, Naim; Koç, Mümin Mehmet; Özcan, Cemile
Removal of heavy metals becomes increasingly crucial for public health and the environment. In this regard, Bi2S3 nanoflowers were produced for heavy metal ion removal applications. Nanoflowers are fabricated using hydrothermal synthesis, and then tested as adsorbents for the removal of lead (Pb2+) ions from aqueous systems. To assess the morphological and chemical characteristics, Bi2S3 nanoflowers were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) techniques. Flame atomic adsorption spectroscopy (FAAS) was used in the assessment of heavy metal ion recovery. To determine the optimum conditions of the adsorption system, the effect of different parameters such as pH, eluent type and amount, adsorbent dose, adsorbent time, etc. were investigated. For lead removal, the optimum pH value was determined as 5.0, eluent dose and type were found 1 M HNO3. For 20 mL, the optimum adsorbent dose and time were found 50.0 mg, and 30 min, respectively. The adsorption capacity of the Bi2S3 nanoflowers was found to be quite higher than the results reported in similar works. It was illustrated that Bi2S3 nanoflowers have great potential to be used in water remediation applications as sorbent material.
AtıfScopus4WoS5OpenAlex5İncele
- MakaleAçık Erişim2023Scopus SJRQ3Morpho-structural and compressive mechanical properties of graphene oxide reinforced hydroxyapatite scaffolds for bone tissue applications
Fidan, Ferzan; Aslan, Naim; Koç, Mümin Mehmet
Hydroxyapatite (HA) is a unique material that has the potential to be used to replace bones and teeth in the field of orthopedics and dentistry since HA exhibits quite similar biological and chemical characteristics to human bone. Hydroxyapatite ceramics are bioactive materials used to repair damaged human tissue. The pores in the porous hydroxyapatite ceramics provide a mechanical interlock, enabling a solid bond and fixation between the implant and bone. In this study, 0.5wt%, 1wt%, and 1.5wt% graphene oxide (GO) reinforced porous HA structures were obtained using the space-holder method to increase the strength of hydroxyapatite with low mechanical strength. NaCl was used as a spacer, and PEG 400 as a binder. Scaffold structures with 40% porosity rates were sintered at 1000 °C under vacuum. Finally, a compression test was applied to the samples which were previously analyzed by SEM, EDS and XRD. The compressive strengths of 0.5%, 1%, and 1.5% graphene oxide reinforced porous HA samples were determined between 8.04 and 31.14 MPa. The highest compressive strength was recorded as 31.14 MPa in the 1% GO added sample, and the lowest compressive strength was recorded as 8.04 MPa in the 1.5% GO added sample. In addition, it was understood that the mechanical properties did not increase regularly with the increase of graphene oxide reinforcing.
AtıfScopus4OpenAlex3
İncele - MakaleYalnız künye2023Scopus SJRQ2Silver-Doped Diamond-Like Carbon (DLC:Ag) Nanocomposite Films for Solar Tracking Applications
Aslan, Naim; Kurt, Mustafa Şükrü; Koç, Mümin Mehmet
Diamond-like carbon (DLC) films are often investigated for their mechanical properties. In this report, we assessed the electrical and photovoltaic characteristics of DLC:Ag composite films produced for solar tracking and/or photodetector device purposes. We used the magnetron sputtering technique to prepare DLC:Ag thin films where DLC and Ag were co-deposited on Si wafers. Structural characterization of the thin films was performed using AFM, EDX, and Raman spectroscopy. Current–voltage, capacitance–voltage and conductance–voltage characterizations were employed to assess the electrical characteristics and photovoltaic characteristics of the DLC:Ag thin films. I–V characteristics were characterized under various illumination intensities to assess the effect of light intensity on the DLC:Ag composite films. We found that silver-doped DLC composite thin films are responsive to light and exhibit detector-like behaviour. Barrier height was found to be between 0.55 eV and 0.81 eV while the ideality factor was calculated to be between 1.94 and 7.11. It was found that photovoltaic and diode properties were affected by applied illumination intensities. C–V characteristics indicated that the electrical properties of the thin films are responsive to the signal frequency. The density of interface states was calculated which was thought to be a factor related to this behaviour.
AtıfScopus17WoS16OpenAlex14İncele
- MakaleAçık Erişim2023Scopus SJRQ2Investigation of fundamental electrical and optoelectronic properties of an organic- and carbon-based MnPc/GC photodiode with high photosensitivity
Aktas, Sitki; Unal, Fatih; Kurt, Mustafa Sukru; Koç, Mümin Mehmet; Arslan, Tayfun; Aslan, Naim; Coşkun, Burhan
The aim of this work is to provide an alternative to optoelectronic devices that use carbon and organic materials. To achieve this, we coated a modified MnPc organic semiconductor compound onto a graphite-like carbon (GC) thin film using the thermal evaporation technique, and fabricated an organic-based, highly light-sensitive MnPc/GC hybrid heterojunction. The heterojunction had a transmittance of approximately 60% in the visible region, an absorption coefficient of ∼106 m−1, and an energy band gap of 2.6 eV. Subsequently, Ag contacts were grown on the surface of each layer, and the Ag/MnPc/GC/Ag photodiode was subjected to fundamental electrical analysis at various light intensities and a ±3 V applied potential. Analysis in a dark environment revealed that the photodiode had a rectification ratio of 2.59 × 103, a series resistance of 28 Ω, and a shunt resistance of 4.17 × 104 Ω, as calculated from Ohm’s law. The diode ideality factor and barrier height of the photodiode were determined from thermionic emission theory to be 5.60 and 0.71 eV, respectively, and it was observed that these decreased with increasing light intensity. The photodetector parameters of the MnPc/GC hybrid photodiode were determined under positive and negative applied potentials at various light intensities. The highest photocurrent, photoconductive responsivity, photosensitivity, and specific detectivity were determined to be 1.512 × 10−1 A, 11.52 A.W−1, 9.83 × 105, and 2.48 × 1012 Jones, respectively, which were significantly higher than those reported in literature for organic and inorganic-based photodiodes. Based on the findings, it was concluded that the Ag/MnPc/GC/Ag photodiode holds promise as an alternative for sensors, solar cells, photodetectors, and optoelectronic communications applications.
AtıfScopus10WoS9OpenAlex14İncele
- MakaleYalnız künye2022Scopus SJRQ2Fe3O4 nanoparticle decorated novel magnetic metal oxide microcomposites for the catalytic degradation of 4-nitrophenol for wastewater cleaning applications
Hasanoğlu Özkan, Elvan; Aslan, Naim; Koç, Mümin Mehmet; Kurnaz Yetim, Nurdan; Sarı, Nurşen
Co3O4, NiO and ZnO microparticles were decorated with Fe3O4 nanoparticles where novel Co3O4@Fe3O4, NiO@Fe3O4 and ZnO@Fe3O4 microcomposites were obtained with significant magnetic properties. Decorating microparticles with Fe3O4 nanoparticles helped us to obtain microcomposites with outstanding magnetic characteristics, since Fe3O4 nanoparticles were decorated on the upper shell of the microstructures where the magnetic characteristics of the composites were not suppressed, and good catalytic performance was obtained. SEM was used to assess the physical morphology of the microparticles which indicate that microparticles were in flower or ball-like shape. Magnetic properties were checked using VSM which revealed that magnetic composites are in ferromagnetic characteristics. Optic characteristics of the particles were checked by UV–Vis spectrometry to assess bandgap energies which indicate that doping microparticles with Fe3O4 slightly alters the bandgap energies of microparticles. The catalytic role of microparticles and microcomposites for the catalytic reduction of 4-nitrophenol to 4-aminophenol was studied.
AtıfScopus21WoS22OpenAlex18İncele
- Kitap BölümüYalnız künye2022X-Ray Computed Tomography and Magnetic Resonance Imaging Applications of Magnetic Nanoalloys and Nanocomposites
Aslan, Naim; Koç, Mümin Mehmet
Metallic nanoparticles were used in different medical and biological applications. Such applications can cover targeted drug delivery, biomarking, MRI imaging, CT imaging, magnetic hyperthermia, etc. Metallic nanoparticles show outstanding properties with high electron affinity and good electrical, electronic, and optoelectronic properties with possible magnetic characteristics. In this regard, magnetic nanoparticles and magnetic nanoalloys are found to be a suitable candidate to be used in imaging applications. In this chapter, concepts of X-ray computed tomography imaging and magnetic resonance imaging are briefly discussed. Magnetic nanoparticles, nanoalloys, and nanocomposites used in imaging, diagnostics, and theranostic applications were illustrated.
AtıfScopus2OpenAlex1İncele
- MakaleAçık Erişim2021Scopus SJRQ2Facile preparation of commercial Bi2O3 nanoparticle decorated activated carbon for pseudocapacitive supercapacitor applications
Üner, Osman; Aslan, Naim; Sarıoğlu, Akın; Semerci, Fatih; Koç, Mümin Mehmet
In this work, a facile method to prepare Bi2O3 decorated activated carbon (Bi2O3@AC) composites with high pseudocapacitive properties was presented. The inorganic–organic composites synthesized using commercial Bi2O3 and active carbon with different weight ratio. The composites were assessed using spectroscopic, microscopic, and diffractive techniques. Our assessments confirmed that active carbons were successfully doped with commercial Bi2O3 nanoparticles with different dopant rates. The electrochemical performance of as-prepared materials was researched by cyclic voltammetry, chronopotentiometry, and electrochemical impedance spectroscopy in 6 M KOH electrolyte. Higher specific capacitance was achieved for increased Bi2O3 nanoparticle in composites. The 20%-Bi2O3@AC had a maximum specific capacitance of 565 F/g at a current density of 1 A/g. In addition, the symmetrically assembled supercapacitor delivers a high energy density (23.0 Wh kg−1). Moreover, 67% of the initial capacitance is maintained after 1500 cycles at 200 mV/s, suggesting good cycling stability. Due to the synergistic effect of compositing a promising electrochemical performance was observed that was not obtained by bare AC or Bi2O3. As a result, the electrochemical properties of 20%-Bi2O3@AC composite is promising and it may be used as potential electrode for supercapacitor.
AtıfScopus29WoS27İncele
- MakaleYalnız künye2020Scopus SJRQ2Metallic nanoparticles as X-Ray computed tomography (CT) contrast agents: A review
Aslan, Naim; Ceylan, Burhan; Koç, Mümin Mehmet; Findik, Fehim
X-ray computed tomography vastly used in both medical purposes and in the research of biological and non-biological materials/samples. Some of the medical applications performed in the clinics requires special protocols where contrast agents may be needed to enhance the contrast. Iodine based contrast agents are commonly used in such applications. Iodine based contrast agents were found hazardous to the environment and some patients has iodine in tolerance due to thyroid origin diseases. Scientists from different fields try to develop contrast agents which can be an alternative to iodine based contrast agents. Metallic nanoparticles have potential to be used as CT contrast agent since metals has high X-ray attenuation and high density. Metal nanoparticles considered as toxic to the living organisms. Covering nanoparticles with organic molecule often reduce toxicity and enhance the biocompatibility. Decoration of nanoparticles with function groups give them targeting properties where special organ and/or tissue can be targeted. Up to now, different studies illustrated the importance of the multipurpose properties of the metallic nanoparticles. In this report, we assessed the metal nanoparticles reported as X-ray computed tomography contrast agent. For the first time in the literature we listed in vivo contrast enhancement, targeted drug delivery and dual/multipurpose imaging properties of each metallic nanoparticles. Therapeutic effects of metallic nanoparticles such as photothermal therapy and magnetic hyperthermia were also addressed. A chart showing relative contrast enhancement properties of the nanoparticles were produced.
AtıfScopus127OpenAlex134İncele
- MakaleYalnız künye2020Scopus SJRQ2Structural, electrochemical and optical properties of hydrothermally synthesized transition metal oxide (Co3O4, NiO, CuO) nanoflowers
Yetim, Nurdan Kurnaz; Aslan, Naim; Sarıoğlu, Akın; Sarı, Nurşen; Koç, Mümin Mehmet
In this work, structural, electrochemical and optical properties of the flower-like Co3O4, NiO and CuO nanostructures were investigated. Co3O4, NiO and CuO nanoflowers were prepared using hydrothermal method. Fourier transform infrared spectroscopy was used in the confirmation of the chemical composition of the nanostructures. X-ray diffraction (XRD) was used in the analysis of crystal structures that peaks observed in the XRD analysis confirms good crystallinity of the nanoflowers. Scanning electron microscopy analysis was used to illustrate the flower-like structure of the nanostructures. Cyclic voltammetry (CV) was used in the assessment of the electrochemical properties. It was seen that flower-like Co3O4, NiO and CuO nanostructures have enhanced electrochemical properties. Using CV results, redox reaction processes of the Co3O4, NiO and CuO nanoflowers were determined. Diffusion constants were determined and NiO nanoflowers found to have the highest diffusion constant among those. Nyquist and Bode diagrams were evaluated. Energy band gaps of Co3O4, NiO, CuO nanoflowers were calculated which were found to be 2.10 eV, 2.25 eV and 3.71 eV, respectively.
AtıfScopus42WoS40OpenAlex46İncele
- Derleme MakaleAçık Erişim2019Scopus SJRQ2Evaluation of X-ray tomography contrast agents: A review of production, protocols, and biological applications
Koç, Mümin Mehmet; Aslan, Naim; Kao, Alexander P.; Barber, Asa H.
X-ray computed tomography is a strong tool that finds many applications both in medical applications and in the investigation of biological and nonbiological samples. In the clinics, X-ray tomography is widely used for diagnostic purposes whose three-dimensional imaging in high resolution helps physicians to obtain detailed image of investigated regions. Researchers in biological sciences and engineering use X-ray tomography because it is a nondestructive method to assess the structure of their samples. In both medical and biological applications, visualization of soft tissues and structures requires special treatment, in which special contrast agents are used. In this detailed report, molecule-based and nanoparticle-based contrast agents used in biological applications to enhance the image quality were compiled and reported. Special contrast agent applications and protocols to enhance the contrast for the biological applications and works to develop nanoparticle contrast agents to enhance the contrast for targeted drug delivery and general imaging applications were also assessed and listed.
AtıfScopus91OpenAlex101İncele
- MakaleAçık Erişim2019Scopus SJRQ2Electrical characterization of solar sensitive zinc oxide doped-amorphous carbon photodiode
Koç, Mümin Mehmet; Aslan, Naim; Erkovan, Mustafa; Aksakal, Bünyamin; Uzun, Orhan; Farooq, W. Aslam; Yakuphanoğlu, Fahrettin
A new solar-sensitive zinc oxide doped-amorphous carbon diode was fabricated using the electrochemical deposition technique. The current-voltage characteristics of the fabricated Al/ZnO-a:C/p-Si/Al diode were investigated under dark and various lighting intensities using both I-V and C-V methods. The fabricated diode was characterized by XRD, SEM-EDS, FTIR and XPS analysis. Through the analysis, it was determined that the photocurrents increased with increasing intensity of incident light. The capacitance-voltage (C-V) characteristics revealed that the capacitance of the diode depended on voltage, frequency and illumination, indicating the existence of a continuous distribution of interface states. It was found that the capacitance changed drastically with changing frequency and separation was observed in different frequencies, as identified in the reverse bias region. The ideality factor obtained was found to be higher than unity, with the average barrier height and ideality factor of the diode were found to be 0.528 ± 0.0069 eV and 5.24 ± 0.39, respectively. The newly fabricated ZnO-doped amorphous carbon (Al/ZnO-a:C/p-Si/Al) photodiode exhibited good solar sensitivity. The overall results indicated that the fabricated Al/ZnO-a:C/p-Si can be used as a solar sensitive diode in optoelectronic device applications as an alternative to graphene-based materials.
AtıfScopus41OpenAlex46İncele
- MakaleAçık Erişim2018Scopus SJRQ3Ti doped amorphous carbon (Al/Ti-a:C/p-Si/Al) photodiodes for optoelectronic applications
Aslan, Naim; Koç, Mümin Mehmet; Dere, Ayşegül; Arif, Bilal; Erkovan, Mustafa; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Yakuphanoglu, Fahrettin
Electrochemical deposition technique was used to fabricate titanium doped amorphous carbon (Ti doped a:C) Al/Ti-a:C/p-Si/Al photodiode. The effects of illumination on the current–voltage (I–V) characteristics of the Al/a:C/p-Si/Al doped Ti diode for optoelectronic applications were investigated. The reverse current of the diode increased with the increasing illumination intensities when the bias voltage was applied. By using the forward bias I–V characteristics, the ideality factor (n) and barrier height (Φb) of Al/Ti-a:C/p-Si photodiode structure was found as 1,84 and 0,50 eV, respectively. In addition, the capacitance–voltage (C–V) and conductance–voltage (G–V) measurements of the diode were studied in the frequency range of 100 kHz–600 kHz. The measured values of the capacitance decreased with the increasing frequency. The photoelectrical properties of Al/Ti-a:C/p-Si/Al device indicates that the photodiode investigated in this paper has great potential to be used in optoelectronic device applications and in industry.
AtıfScopus41OpenAlex43İncele




