Materials Science and Engineering / Malzeme Bilimi ve Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4719
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Article Citation - WoS: 11Citation - Scopus: 13Magnesium-Ion Battery Anode From Polymer-Derived Sioc Nanobeads(Wiley, 2023) Guo, Wuqi; Kober, Delf; Gurlo, Aleksander; Bekheet, Maged F.; İçin, Öykü; Ahmetoğlu, Çekdar VakıfTin-containing silicon oxycarbide (SiOC/Sn) nanobeads are synthesized with different carbon/tin content and tested as electrodes for magnesium-ion batteries. The synthesized ceramics are characterized by thermogravimetric-mass spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, N2 sorption analysis, scanning electron microscope, energy-dispersive X-ray, and elemental analysis. Galvanostatic cycling tests, rate performance tests, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) tests, and ex situ XRD measurements are conducted. Results of battery performance tests present a high capacity of 198.2 mAh g-1 after the first discharging and a reversible capacity of 144.5 mAh g-1 after 100 cycles at 500 mA g-1. Excellent rate performance efficiency of 85.2% is achieved. Battery performances in this research are influenced by surface area, and tin contentof the SiOC/Sn nanobeads. EIS, CV tests, and ex situ XRD measurements reveal that higher surface area contributes to higher capacity by providing more accessible Mg2+ ion storage sites and higher rate capability by improving the diffusion process. Higher Sn content increases battery capacity through reversible Mg-Mg2Sn-Mg alloying/dealloying process and improves the rate performances by increasing electrical conductivity. Besides, SiOC advances cycling stability by preventing electrode collapse and enhances the capacity due to higher surface capacitive effects. SiOC nanobeads containing Sn nanoparticles are synthesized and tested as anode for magnesium-ion batteries. The anodes show high performance with reversible capacity of 144.5 mAh g-1 after 100 cycles at 500 mA g-1 and excellent rate performance efficiency of 85.2% from 50 to 500 mA g-1.imageArticle Citation - WoS: 3Citation - Scopus: 2Targeted Multidrug Delivery Systems To Kill Antibiotic-Resistant Staphylococcus Aureus(Editions de Sante, 2023) Özalp, Veli Cengiz; Ucak, Samet; Dursun, Ali D.; Sudağıdan, Mert; İçin, Öykü; Ahmetoğlu, Çekdar Vakıf; Henning, Laura M.; Simon, Ulla; Gurlo, AleksanderDifferent ordered mesoporous silica (OMS) nanoparticles, ranging from regular COK-12 to COK-12 modified in terms of pore shape and size, have been employed as standard drug carriers for the controlled adsorption and release of drug molecules in comparison to well-known OMS SBA-15 and MCM-41. The cytotoxicity analysis demonstrated that regular COK-12 particles were less harmful to mammalian cultured cells, causing lower apoptosis induction than modified COK-12, MCM-41, and SBA-15 particles. Thus, regular COK-12 was further used to prepare a dual antibiotic-loaded drug delivery material, followed by surface functionalization with Staphylococcus aureus-specific aptamers for targeting. The results demonstrated that the joint loading of lysozyme and vancomycin in regular COK-12 improved the ability of the antibiotic treatments to kill methicillin-resistant Staphylococcus strains via aptamer targeting. The minimum inhibitory concentration (MIC) values decreased 4.1-fold and 12-fold compared to the non-targeted use of the antimicrobial agents in homogeneous solutions for vancomycin and lysozyme, respectively, clearly demonstrating the high potential of COK-12 to be used as a carrier in multidrug therapy. © 2023 Elsevier B.V.Article Citation - WoS: 28Citation - Scopus: 33Cold Sintering as a Promising Isru Technique: a Case Study of Mars Regolith Simulant(Elsevier, 2023) Karacasulu, Levent; Karl, David; Gurlo, Aleksander; Ahmetoğlu, Çekdar VakıfMars regolith simulant (MGS-1) was densified for the first time via a cold sintering process (CSP) as a novel in-situ resource utilization (ISRU) concept. The technique comprises the utilization of NaOH solution as a liquid media during the densification of simulant powder with <100 μm particle size. In as short as 30 min, with the increase in the NaOH concentration (from 3 M to 10 M) and processing temperature (from 150 °C to 250 °C), the relative densities of the regolith compacts and the mechanical properties were enhanced. The artifacts produced with Mars regolith simulant powder at 250 °C using 10 M NaOH solution yielded a relative density of around 88% and compressive strength reaching ∼45 MPa.Article Citation - WoS: 18Citation - Scopus: 22Effect of Fomes Fomentarius Cultivation Conditions on Its Adsorption Performance for Anionic and Cationic Dyes(American Chemical Society, 2022) Henning, Laura M.; Simon, Ulla; Abdullayev, Amanmyrat; Schmidt, Bertram; Pohl, Carsten; Nunez Guitar, Tamara; Ahmetoğlu, Çekdar Vakıf; Meyer, Vera; Bekheet, Maged F.; Gurlo, AleksanderLab-cultivated mycelia of Fomes fomentarius (FF), grown on a solid lignocellulose medium (FF-SM) and a liquid glucose medium (FF-LM), and naturally grown fruiting bodies (FF-FB) were studied as biosorbents for the removal of organic dyes methylene blue and Congo red (CR). Both the chemical and microstructural differences were revealed using X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, zeta potential analysis, and scanning electron microscopy, illuminating the superiority of FF-LM and FF-SM over FF-FB in dye adsorption. The adsorption process of CR on FF-LM and FF-SM is best described by the Redlich-Peterson model with β constants close to 1, that is, approaching the monolayer Langmuir model, which reach maximum adsorption capacities of 48.8 and 13.4 mg g-1, respectively, in neutral solutions. Adsorption kinetics follow the pseudo-second-order model where chemisorption is the rate-controlling step. While the desorption efficiencies were low, adsorption performances were preserved and even enhanced under simulated dye effluent conditions. The results suggest that F. fomentarius can be considered an attractive biosorbent in industrial wastewater treatment and that its cultivation conditions can be specifically tailored to tune its cell wall composition and adsorption performance.Article Citation - WoS: 34Citation - Scopus: 36Polymer derived ceramic aerogels(Pergamon-Elsevier Science Ltd, 2021) Ahmetoğlu, Çekdar Vakıf; Semerci, Tuğçe; Gurlo, Aleksander; Soraru, Gian DomenicoAerogels are unique porous solids having exceptional low relative density together with high specific surface area, making them very attractive materials for scientific research and industrial applications. Polymer derived ceramic aerogels are a new class of materials obtained through the pyrolysis of sol-gel/preceramic polymers. Herein this review, some of the representative formation methods and applications of polymer derived ceramic aerogels are highlighted with a specific focus on the thermal, electrical, and adsorbent related properties.