Browsing by Author "Şahin, Ömer"

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Benzenin Buhar-fazı Adsorpsiyonunun İyileştirilmesi için Etkili Nano-adsorbentler Olarak Silika-kaplı Manyetik Fe3o4 Nanoparçacıkları
(2021) Kutluay, Sinan; Ece, Mehmet Sakır; Şahin, Ömer
Bu çalışma, benzenin buhar-fazı adsorpsiyonunun iyileştirilmesi için silika-kaplı Fe3O4 (Fe3O4@SiO2) hazırlanmasına odaklandı. Fe3O4@SiO2 birlikte çökeltme yöntemi ile hazırlanırken karakterizasyonu FT-IR, SEM ve BET yüzey alanı analizleri kullanılarak gerçekleştirildi. Deneysel parametreler, yanıt yüzey metodolojisi (RSM) kullanılarak benzenin buhar-fazı adsorpsiyonu için değerlendirildi. Fe3O4@SiO2, aşağıdaki optimum koşullar altında 197,50 mg g-1 buhar-fazı benzeni adsorbe etti: 39,93 dakika kalma süresi, 13,57 mg l-1 başlangıç benzen konsantrasyonu ve 26,87°C sıcaklık. Benzenin Fe3O4@SiO2 üzerindeki buhar fazı adsorpsiyon mekanizması, DubininRadushkevich (D-R), Freundlich ve Langmuir dahil izotermler incelenerek netleştirildi ve deneysel veriler D-R modeline iyi bir şekilde uyduruldu. Benzenin Fe3O4@SiO2 üzerindeki buhar-fazı adsorpsiyon kinetiği, sözde birinci-dereceden (SBD) model ve sözde ikinci dereceden (SİD) model gibi kinetikler incelenerek netleştirildi, ve deneysel sonuçlar SİD modele uydu. Bu çalışma, Fe3O4@SiO2'nin umut verici düşük maliyetli nano-adsorbent olarak uygulama potansiyelini gösterdi.
Derik Halhalı Zeytin Çekirdeğinden Çevre Dostu Selülozik Manyetik Nano-adsorbent Üretimi ve Benzen Gideriminde Kullanılması
(2021) Kahraman, Zafer; Atku, Fesih; Şahin, Ömer; Kutluay, Sinan; Ece, Mehmet Sakır; Önal, Ferat
Uçucu organik bir bileşik (UOB) olan benzen, kimyasal ve petrokimyasal gibi faaliyetlerle sanayiden ve endüstriden atmosfere salınmaktadır. Benzen, canlı sağlığı ve çevre için ağır kirliliklerden biri olup, kanserojen, mutajenik ve oldukça toksik polar olmayan bir kirleticidir. İnsan sağlığı ve ekolojik çevre için bir potansiyel tehlikedir. Bu sebeple benzenin bir kirletici olarak atmosferden uzaklaştırılması büyük önem taşımaktadır. Bu çevresel iyileştirme çalışmasında, Derik Halhalı zeytininin çekirdeği bir doğal selüloz (DS) kaynağı olarak manyetit ($Fe_3O_4$) modifikasyonunda kullanıldı. Başarıyla üretilen $Fe_3O_4$/DS nano-adsorbentin benzen giderimine karşı adsorpsiyon özellikleri incelendi. Birlikte çökeltme yöntemiyle elde edilen Fe3O4/DS nano-adsorbenti SEMEDS, FTIR ve BET analizleri ile karakterize edildi. Benzen giderim prosesinde, benzen başlangıç konsantrasyonu, adsorbent miktarı, adsorpsiyon süresi ve adsorpsiyon sıcaklığı gibi farklı parametrelerin etkileri değerlendirildi. Optimum değerler olarak belirlenen 90 dakika adsorpsiyon süresi, 15 ppm benzen başlangıç konsantrasyonu, 100 mg adsorbent miktarı ve 25°C adsorpsiyon sıcaklığı gibi koşullar altında benzen adsorpsiyon kapasitesi 298.15 mg/g olarak bulundu. Bu sonuç, başarıyla üretilen $Fe_3O_4$/DS nano-adsorbentin UOB kirleticilerin giderimindeki uygulama potansiyelini ortaya koymaktadır. Öte yandan, Quasi-birinci-dereceden kinetik modeli takip eden gaz halindeki benzenin $Fe_3O_4$/DS nano-adsorbenti üzerine adsorpsiyon prosesi fiziksel adsorpsiyon mekanizmasını işaret etmektedir. Ayrıca, 1.74 kJ/mol olarak hesaplanan E değeri (Dubinin-Radushkevich model sabiti) adsorpsiyon prosesinin fiziksel etkileşim mekanizması üzerinden gerçekleştiğini desteklemektedir. Son olarak, beş döngüden sonra, $Fe_3O_4$/DS nano-adsorbentin %90.61'lik bir yeniden kullanım verimini koruduğu bulundu, bu da nano-adsorbentin pratik uygulamalarda büyük bir potansiyele sahip olduğu anlamına geliyor.
Development of Novel Fe3O4/AC@SiO2@1,4-DAAQ Magnetic Nanoparticles with Outstanding VOC Removal Capacity: Characterization, Optimization, Reusability, Kinetics, and Equilibrium Studies
(Industrial and Engineering Chemistry Research, 2021) Ece, Mehmet Şakir; Kutluay, Sinan; Şahin, Ömer; Horoz, Sabit
The adsorption of pollutants to the surface of adsorbents plays a critical role in the effectiveness of adsorption technology for air purification applications. Herein, novel magnetic nanoparticles functionalized with 1,4-diaminoanthraquinone (1,4-DAAQ), namely, Fe3O4/activated carbon (AC)@SiO2@1,4-DAAQ, were innovatively synthesized via co-precipitation and sol-gel techniques. After that, these nanoparticles were used for high-efficiency removal of volatile organic compounds (VOCs) (i.e., benzene and toluene). The synthesized nanoparticles were characterized by various techniques such as Fourier transform IR spectroscopy, thermogravimetric analysis/differential thermal analysis, scanning electron microscopy, and Brunauer-Emmett-Teller analysis. The dynamic adsorption process of VOCs was optimized based on operating parameters. The adsorption experiments revealed that Fe3O4/AC@SiO2@1,4-DAAQ showed exceptional performance for the removal of VOCs. It was observed that for benzene, Fe3O4, AC, Fe3O4/AC, Fe3O4/AC@SiO2, and Fe3O4/AC@SiO2@1,4-DAAQ exhibited dynamic adsorption capacities of 180.25, 228.87, 295.84, 382.10, and 1232.77 mg/g, respectively. Additionally, for toluene, they exhibited dynamic adsorption capacities of 191.08, 274.53, 310.26, 421.30, and 1352.16 mg/g, respectively. This indicated that the modification of 1,4-DAAQ could greatly enhance the dynamic adsorption capacity of Fe3O4/AC@SiO2@1,4-DAAQ for VOCs. In addition to the apparent adsorptive behavior in removing VOCs, Fe3O4/AC@SiO2@1,4-DAAQ exhibited high repeatability. After ten consecutive adsorption/desorption cycles, for benzene and toluene, Fe3O4/AC@SiO2@1,4-DAAQ retained 79.36 and 78.24% of its initial adsorption capacity, respectively. According to the characterization results, the average pore diameter for Fe3O4/AC@SiO2@1,4-DAAQ was determined to be 24.46 nm, indicating that they were in the mesopore range. The adsorption mechanism of the VOCs on Fe3O4/AC@SiO2@1,4-DAAQ was clarified by investigating the isotherm and kinetic criteria in detail. Isotherm models suggested that the adsorption process of VOCs is physical. Moreover, from the analysis of diffusion-based rate-limiting kinetic models, the findings reveal a combination of intraparticle diffusion as well as film diffusion throughout the adsorption process of VOCs. In addition, it was concluded from the analysis of the mass transfer model factors that global mass transfer and internal diffusion are more effective than film diffusion. The results demonstrated that the Fe3O4/AC@SiO2@1,4-DAAQ nanoadsorbent is a promising material for the effective removal of VOCs.
Fabrication and characterization of 3,4-diaminobenzophenone-functionalized magnetic nanoadsorbent with enhanced VOC adsorption and desorption capacity
(Environmental Science and Pollution Research, 2021) Ece, Mehmet Şakir; Şahin, Ömer; Kutluay, Sinan; Horoz, Sabit
The present study, for the first time, utilized 3,4-diaminobenzophenone (DABP)-functionalized Fe3O4/AC@SiO2 (Fe3O4/AC@SiO2@DABP) magnetic nanoparticles (MNPs) synthesized as a nanoadsorbent for enhancing adsorption and desorption capacity of gaseous benzene and toluene as volatile organic compounds (VOCs). The Fe3O4/AC@SiO2@DABP MNPs used in adsorption and desorption of benzene and toluene were synthesized by the co-precipitation and sol-gel methods. The synthesized MNPs were characterized by SEM, FTIR, TGA/DTA, and BET surface area analysis. Moreover, the optimization of the process parameters, namely contact time, initial VOC concentration, and temperature, was performed by applying response surface methodology (RSM). Adsorption results demonstrated that the Fe3O4/AC@SiO2@DABP MNPs had excellent adsorption capacity. The maximum adsorption capacities for benzene and toluene were found as 530.99 and 666.00 mg/g, respectively, under optimum process parameters (contact time 55.47 min, initial benzene concentration 17.57 ppm, and temperature 29.09 °C; and contact time 57.54 min, initial toluene concentration 17.83 ppm, and temperature 27.93 °C for benzene and toluene, respectively). In addition to the distinctive adsorptive behavior, the Fe3O4/AC@SiO2@DABP MNPs exhibited a high reproducibility adsorption and desorption capacity. After the fifth adsorption and desorption cycles, the Fe3O4/AC@SiO2@DABP MNPs retained 94.4% and 95.4% of its initial adsorption capacity for benzene and toluene, respectively. Kinetic and isotherm findings suggested that the adsorption mechanisms of benzene and toluene on the Fe3O4/AC@SiO2@DABP MNPs were physical processes. The results indicated that the successfully synthesized Fe3O4/AC@SiO2@DABP MNPs can be applied as an attractive, highly effective, reusable, and cost-effective adsorbent for the adsorption of VOC pollutants. Graphical abstract[Figure not available: see fulltext.]
Fabrication and characterization of Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide magnetic nanomaterials
(SpringerLink, 2022) Kutluay, Sinan; Şahin, Ömer; Ece, Mehmet Şakir
Abstract In this study, the fabrication of perlite-supported Fe3O4 (Fe3O4/perlite), SiO2-coated Fe3O4/perlite (Fe3O4/perlite@SiO2), and sulfanilamide-modified Fe3O4/perlite@SiO2 (Fe3O4/perlite@SiO2@sulfanilamide) magnetic nanomaterials and their characterization by various spectroscopic techniques were presented. For this purpose, first, Fe3O4/perlite was fabricated via the co-precipitation method. Then, Fe3O4/perlite@SiO2 and Fe3O4/perlite@SiO2@sulfanilamide nanomaterials were fabricated using the sol–gel method. The structural properties of the fabricated nanomaterials were characterized using Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), SEM-energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis-differential thermal analysis, and X-ray diffraction (XRD) analyses. The SEM, SEM–EDX, FTIR, and XRD analyses revealed that the fabrication and surface coatings of the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide were successfully performed. It was concluded that the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide showed a type IV-H3 hysteresis loop according to the International Union of Pure and Applied Chemistry classification. According to the BET analysis, it was found that the specific surface areas of the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide were 8.09, 12.71, and 5.89 m2/g, respectively. The average pore radius of the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide were 9.68, 7.91, and 34.69 nm, respectively, using the Barrett-Joyner-Halenda method. Moreover, the half-pore widths of the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide were 2.27, 1.58, and 17.99 nm, respectively, using the density functional theory method. Furthermore, in light of characterization findings, the Fe3O4/perlite, Fe3O4/perlite@SiO2, and Fe3O4/perlite@SiO2@sulfanilamide were in crystalline cubic spinel form, and they had mechanical and thermal stability and a mesoporous structure. Within the framework of the results, these developed nanomaterials, which have potential in many applications, such as sustainable technologies and environmental safety technologies, were brought to the attention of related fields.
Facile synthesis and comprehensive characterization of Ni-decorated amine groups-immobilized Fe3O4@SiO2 magnetic nanoparticles having enhanced solar cell efficiency
(Journal of Materials Science: Materials in Electronics, 2021) Ece, Mehmet Şakir; Ekinci, Arzu; Kutluay, Sinan; Şahin, Ömer; Horoz, Sabit
In this study, the synthesis and comprehensive characterization of Fe3O4@SiO2 magnetic nanoparticles (MNPs) immobilized with L-Arginine decorated with nickel (Ni) was achieved, and their ability in solar cell efficiency was evaluated. Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@L-Arginine and Fe3O4@SiO2@L-Arginine-Ni MNPs were prepared by co-precipitation and sol-gel methods. The structural, morphological, optical and textural properties of the prepared MNPs were clarified by Fourier Transform Infrared Spectroscopy (FTIR), Energy-Dispersive X-Ray (EDX), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET), Thermal Gravimetric Analysis (TGA) and Ultraviolet-Visible (UV-Vis) analyzes. From the BET data, it is understood that the specific surface area of the prepared Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@L–Arginine MNPs is 60.85, 28.99 and 29.84 m2/g, respectively. From the pore size distribution determined by Barrett-Joyner-Halenda (BJH) method, it was understood that the pore radius of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@L–Arginine MNPs were in the range of mesopore and the average pore radius was equal to approximately 11.03, 9.11 and 28.45 nm, respectively. It is assumed that the half pore widths calculated by the density functional theory (DFT) method of the prepared of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@L-Arginine MNPs are 5.58, ∼ 0.88, and ∼ 17.98 nm, respectively. The energy band gap of the prepared MNPs with spinel structure was determined as approximately 3.10 eV. In addition to the structural, morphological, optical and textural properties, the photovoltaic properties of the prepared MNPs were examined. Au/CuO/Fe3O4@SiO2@L–Arginine-Ni/ZnO/SnO2:F solar cell device was created by using existing Fe3O4@SiO2@L–Arginine-Ni MNPs as buffer layer. The power conversion efficiency (%) of the prepared Fe3O4@SiO2@L–Arginine-Ni MNPs based solar cell device was calculated as 1.84 %. This numerical result shows that the prepared Fe3O4@SiO2@L-Arginine-Ni MNPs can be used as a promising buffer layer in a solar structure.
Highly improved solar cell efficiency of Mn-doped amine groups-functionalized magnetic Fe3O4@SiO2 nanomaterial
(Wiley Online Library, 2021) Kutluay, Sinan; Horoz, Sabit; Şahin, Ömer; Ekinci, Arzu
Herein, magnetic Fe3O4@SiO2 nanomaterial functionalized with amine groups (Fe3O4@SiO2@IPA) doped with manganese (Mn) was prepared, characterized and used for solar cell application. Fe3O4@SiO2@IPA-Mn was prepared via the co-precipitation and sol-gel techniques. Energy-dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurements were performed to examine the structure of Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@IPA and Fe3O4@SiO2@IPA-Mn. General morphology and textural properties of the prepared magnetic nanomaterials were clarified by Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM). In addition, Ultraviolet-visible (UV-Vis) spectroscopy and thermal gravimetric analysis (TGA) were used to have a knowledge about the energy band gap and thermal behavior of the prepared magnetic nanomaterials. The energy band gap of Fe3O4@SiO2@IPA with spinel structure was determined as approximately 2.48 eV. It was understood that Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA showed type IV-H3 hysteresis cycle according to IUPAC. From the BET data, it was determined that the specific surface areas of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were 60.85, 28.99 and 40.41 m(2)/g, respectively. The pore size distributions of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were calculated as 8.55, 1.53 and 1.70 nm, respectively, by the BJH method. Also, it was observed that the dominant pore widths of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were calculated similar to 5.58, similar to 0.88 and similar to 17.92 nm, respectively, by the DFT method. Au/CuO/Fe3O4@SiO2@IPA-Mn/ZnO/SnO2: F solar cell device was created using existing Fe3O4@SiO2@IPA-Mn as a buffer layer. The power conversion efficiency (%) of Fe3O4@SiO2@IPA-Mn based solar cell device was calculated as 2.054. This finding suggest that Fe3O4@SiO2@IPA-Mn can be used as a promising sensitizer in solar cell technology. Moreover, in this study, the effectiveness of the modification of manganese (one of the transition metals, which is cheap and easily available) with magnetic nanomaterials in the use of solar cell technology was demonstrated for the first time.
Hydrogen production by using Ru nanoparticle decorated with Fe3O4@SiO2–NH2 core-shell microspheres
(International Journal of Hydrogen Energy, 2020) Ece, Mehmet Şakir; İzgi, Mehmet Sait; Kazıcı, Hilal Çelik; Şahin, Ömer; Onat, Erhan
Noble metals are commonly used in order to accelerate the NH3BH3 hydrolysis for H2 production as heterogeneous catalysts. The nanoparticles (NPs) of these metals can be applied as active catalysts in fluid reactions. Metal NPs included in the core-shell nanostructures emerged as well-defined heterogeneous catalysts. Additionally, unsupported NPs catalysts can be gathered easily among neighboring NPs and the separation/recovery of these catalysts are not efficient with traditional methods. For this reason, here, silica-shell configuration was designed which was functionalized with a magnetic core and amine groups and Ru NPs were accumulated on Fe3O4@SiO2–NH2 surface for H2 production from NH3BH3. Fe3O4@SiO2–NH2–Ru catalysts demonstrated high catalytic activity as long as it has a hydrogen production rate of 156381.25 mLgcat−1 min−1 and a turnover frequency (TOF) of 617 molH2molcat−1min−1 towards the hydrolysis dehydrogenation of AB at 30 °C. This result is significantly higher than most of the known catalysts.
Manyetik Fe3o4/aktif Karbon Nanoparçacıklarının Sentezlenmesi ve Adsorpsiyon Prosesi ile Gaz-fazındaki Toluenin Giderilmesi için Uygulanması
(2020) Kutluay, Sinan; Şahin, Ömer; Ece, Mehmet Sakır
Bu çalışmada, gaz-fazı toluenin adsorpsiyon prosesi ile giderilmesi için nano-adsorbent olarak aktif karbon ile fonksiyonelleştirilmiş manyetik Fe3O4 (Fe3O4/AC)'nin ilk uygulamasını sunuyoruz. Manyetik Fe3O4/AC, nanoteknoloji prensipleri çerçevesinde birlikte çöktürme yöntemi ile sentezlendi. Daha sonra, temas süresi, başlangıç toluen konsantrasyonu ve sıcaklık gibi proses koşullarının toluenin manyetik Fe3O4/AC ile adsorpsiyonu üzerindeki etkileri yanıt yüzeyi yöntemi (RSM) kullanılarak incelendi. Elde edilen manyetik Fe3O4/AC, taramalı elektron mikroskopisi (SEM), fourier dönüşümü kızılötesi spektroskopisi (FTIR) ve termogravimetrik (TG) analiz kullanılarak karakterize edildi. Toluenin adsorpsiyonu için manyetik Fe3O4/AC’ nin maksimum adsorpsiyon kapasitesi, 59,48 dakika temas süresi, 17,21 mg l-1 başlangıç toluen konsantrasyonu ve 26,01°C sıcaklıktaki proses koşulları altında 312,99 mg g -1 olarak belirlendi. Manyetik Fe3O4/AC tarafından adsorpsiyon, Langmuir izoterm modeli ile en iyi uyumu gösterdi ve sözde ikinci dereceden (PSO) kinetik modele uydu. Bu çalışma, manyetik Fe3O4/AC’nin, gaz-fazı toluenin giderilmesi için bir adsorbent olarak uygulanabileceğini gösterdi.