Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 4Citation - Scopus: 4Tailored Bodipy-Based Fluorogenic Probes for Phosgene Detection: a Comparative Evaluation of Recognition Sites(Royal Soc Chemistry, 2024) Dartar, Suay; Emrullahoğlu, Mustafa; Kaya, Beraat Umur; Kaya, Beraat Umur; Yayak, Yanki Oncu; Vural, Ezgi; Vural, Ezgi; Dartar, Suay; Emrullahoglu, Mustafa; 01. Izmir Institute of Technology; 04.01. Department of Chemistry; 04.04. Department of Photonics; 04. Faculty of ScienceWe constructed two novel boron-dipyrromethene (BODIPY)-based fluorescent probes, BOPD and BOBA, each equipped with the phosgene specific recognition units o-phenylenediamine (OPD) and o-aminobenzylamine (OBA) at the 2-position of the BODIPY core. BOPD and BOBA represent rare examples of BODIPY-based probes that operate by modulating an intramolecular charge transfer process (ICT), as validated by computational studies. We systematically compared the analytic performance of those recognition units while focusing on selectivity, fluorescence turn-on ratios and response times. Probe BOBA, equipped with OBA as the recognition unit, demonstrated a remarkably low detection limit (i.e., 1.40 nM) and a rapid response time (<10 s) for triphosgene. By comparison, BOPD, featuring an OPD unit, showed superior selectivity towards triphosgene, with a detection limit of 93 nM and a response time of up to 30 s. A portable sensing platform was developed by loading BOPD onto test strips made of TLC plates, nonwoven materials and small-headed cotton swabs, which were assessed for their effectiveness in detecting phosgene. We additionally performed the first successful application of a fluorescent probe, namely BOPD, for monitoring the accumulation of phosgene in plants.Article Citation - WoS: 2Citation - Scopus: 2Stabilization of the First-Order Phase Transition Character and Enhancement of the Electrocaloric Effect by Na<sub>0.5</Sub>bi<sub>0.5< Substitution in Batio<sub>3</Sub> Ceramics(Royal Soc Chemistry, 2024) Karakaya, Merve; Adem, Umut; Fulanovic, Lovro; Adem, Umut; 03.09. Department of Materials Science and Engineering; 01. Izmir Institute of Technology; 03. Faculty of EngineeringThe electrocaloric properties of BaTiO3-based Pb-free ferroelectric materials are widely investigated. One approach to achieving a large electrocaloric response is making use of the substantial polarization change associated with the first-order phase transition at the Curie temperature. To make use of this approach, we have investigated the electrocaloric response of (1 - x)BaTiO3-xNa0.5Bi0.5TiO3 (BT-NBT) ceramics for x = 0.05, 0.10, 0.20 and 0.30. For this BT-rich part of the solid solution, it is established that increasing the NBT content increases the tetragonality of the BaTiO3. We show that this increase in tetragonality with NBT substitution helps to maintain the first-order nature of the phase transition in BaTiO3 and correspondingly a large electrocaloric response, despite the simultaneous enhancement of relaxor ferroelectric character with the NBT substitution. A significantly larger effective electrocaloric temperature change (Delta Teff) of 1.65 K was obtained for the x = 0.20 sample under 40 kV cm-1, using the direct measurement of the electrocaloric effect, which is in reasonable agreement with the indirect measurements.Article Citation - WoS: 1Citation - Scopus: 2Concurrent Boron Removal From Reverse Osmosis Concentrate and Energy Production Using a Microbial Desalination Cell-Donnan Dialysis Hybrid System(Royal Soc Chemistry, 2024) Gören, Ayşegül Yağmur; Ökten, Hatice Eser; 03.07. Department of Environmental Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThe removal of boron from aqueous solutions offers an important opportunity to improve the management of sustainable resources. In this regard, microbial desalination cells (MDCs) are a promising bioelectrochemical approach for effective water treatment, but the integrated MDC-Donnan Dialysis (DD) process for boron removal from reverse osmosis (RO) concentrated effluents has not been investigated before. Integration of the DD process with MDC is investigated in this paper for the first time to enhance the efficiency of the process by providing pre-treatment and natural pH manipulation. Therefore, the MDC process was evaluated for boron removal from boron-containing synthetic solution, geothermal water, and RO-concentrated effluent with the help of the DD system. The highest boron removal performance, with an efficiency of 72.1% in the desalination chamber and 74.8% in the DD-feed chamber, was obtained for boron-containing synthetic solution, while the COD removal efficiency was almost 90% in all water resources. However, the maximum power density was 4818 mW m-2 with a closed circuit voltage of 1317 mV for RO concentrated water treatment due to its high ionic strength. Moreover, the most crucial output of this study is that the pH value of the system did not need to be adjusted continuously to convert the uncharged boric acid into the borate ion in the charged form owing to better manipulation of the pH by the DD system. Overall, the integrated MDC-DD system provided promising results, presenting effective boron-containing water desalination, yeast wastewater treatment, and enhanced energy production.Review Citation - WoS: 10Citation - Scopus: 12Trends in Authentication of Edible Oils Using Vibrational Spectroscopic Techniques(Royal Soc Chemistry, 2024) Özen, Fatma Banu; Çavdaroğlu, Çağrı; Tokatlı, Figen; 03.08. Department of Food Engineering; 01. Izmir Institute of Technology; 03. Faculty of EngineeringThe authentication of edible oils has become increasingly important for ensuring product quality, safety, and compliance with regulatory standards. Some prevalent authenticity issues found in edible oils include blending expensive oils with cheaper substitutes or lower-grade oils, incorrect labeling regarding the oil's source or type, and falsely stating the oil's origin. Vibrational spectroscopy techniques, such as infrared (IR) and Raman spectroscopy, have emerged as effective tools for rapidly and non-destructively analyzing edible oils. This review paper offers a comprehensive overview of recent advancements in using vibrational spectroscopy for authenticating edible oils. The fundamental principles underlying vibrational spectroscopy are introduced and chemometric approaches that enhance the accuracy and reliability of edible oil authentication are summarized. Recent research trends highlighted in the review include authenticating newly introduced oils, identifying oils based on their specific origins, adopting handheld/portable spectrometers and hyperspectral imaging, and integrating modern data handling techniques into the use of vibrational spectroscopic techniques for edible oil authentication. Overall, this review provides insights into the current state-of-the-art techniques and prospects for utilizing vibrational spectroscopy in the authentication of edible oils, thereby facilitating quality control and consumer protection in the food industry. The authentication of edible oils has become increasingly important for ensuring product quality, safety, and compliance with regulatory standards.Article Citation - WoS: 1Citation - Scopus: 1Thickness-Dependent Characteristics and Oxidation of 2d-Cadmium(Royal Soc Chemistry, 2024) Şahin, Hasan; Sahin, Hasan; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyIn this study, the structural, electronic, and vibrational properties of the thinnest crystal structure that can be obtained by thinning bulk Cd down to a monolayer are investigated by performing first-principles calculations. Total energy optimization and dynamic stability calculations reveal that the single layer crystal structure has a hexagonal unitcell with a two-atomic basis where alternating layers are formed by trigonal arrangements of Cd atoms. Softening occurs with decreasing zone center optical phonon frequencies as a result of structural relaxation when going from a bulk to a single layer (SL) structure. It is also shown that the thinnest structure obtained from bulk Cd crystals maintains its metallic features despite the dimensional crossover. In addition, it is predicted through calculations that the SL Cd crystal strongly interacts with oxygen and that the oxidized regions even undergo chemical transformation to form a CdO crystal. In the double-layer CdO crystal resulting from the oxidation of individual Cd layers, the layers are connected to each other with partially covalent bonds, and this structure is a semiconductor with a band gap of 2.10 eV. On the one hand, the robust metallic structure of the thinnest possible Cd crystal provides flexibility for its use in nanoscale applications, on the other hand, the fact that its electronic properties can be changed by oxidation is important for optoelectronic device applications. In this study, the structural, electronic, and vibrational properties of the thinnest crystal structure that can be obtained by thinning bulk Cd down to a monolayer are investigated by performing first-principles calculations.Article Citation - WoS: 1Anisotropic Structural, Vibrational, Electronic, Optical, and Elastic Properties of Single-Layer Hafnium Pentatelluride: an <i>ab Initio</I> Study(Royal Soc Chemistry, 2024) Yağmurcukardeş, Mehmet; Cetin, Zebih; Yagmurcukardes, Mehmet; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyMotivated by the highly anisotropic nature of bulk hafnium pentatelluride (HfTe<INF>5</INF>), the structural, vibrational, electronic, optical, and elastic properties of single-layer two-dimensional (2D) HfTe<INF>5</INF> were investigated by performing density functional theory (DFT)-based first-principles calculations. Total energy and geometry optimizations reveal that the 2D single-layer form of HfTe<INF>5</INF> exhibits in-plane anisotropy. The phonon band structure shows dynamic stability of the free-standing layer and the predicted Raman spectrum displays seven characteristic Raman-active phonon peaks. In addition to its dynamic stability, HfTe<INF>5</INF> is shown to exhibit thermal stability at room temperature, as confirmed by quantum molecular dynamics simulations. Moreover, the obtained elastic stiffness tensor elements indicate the mechanical stability of HfTe<INF>5</INF> with its orientation-dependent soft nature. The electronic band structure calculations show the indirect-gap semiconducting behavior of HfTe<INF>5</INF> with a narrow electronic band gap energy. The optical properties of HfTe<INF>5</INF>, in terms of its imaginary dielectric function, absorption coefficient, reflectance, and transmittance, are shown to exhibit strong in-plane anisotropy. Furthermore, structural analysis of several point defects and their oxidized structures was performed by means of simulated STM images. Among the considered vacancy defects, namely , , V<INF>Te<INF>out</INF></INF>, V<INF>Te<INF>in</INF></INF>, , and V<INF>Hf</INF>, the formation of V<INF>Te<INF>out</INF></INF> is revealed to be the most favorable defect. While and V<INF>Hf</INF> defects lead to local magnetism, only the oxygen-substituted V<INF>Hf</INF> structure possesses magnetism among the oxidized defects. Moreover, it is found that all the bare and oxidized vacant sites can be distinguished from each other through the STM images. Overall, our study indicates not only the fundamental anisotropic features of single-layer HfTe<INF>5</INF>, but also shows the signatures of feasible point defects and their oxidized structures, which may be useful for future experiments on 2D HfTe<INF>5</INF>.Article Citation - WoS: 1Citation - Scopus: 1Experimental and Theoretical Investigation of Synthesis and Properties of Dodecanethiol-Functionalized Mos<sub>2</Sub>(Royal Soc Chemistry, 2023) Duran, Tuna A.; Şahin, Hasan; Şahin, Hasan; Milosevic, Milorad V.; Sahin, Hasan; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyHerein, we investigate the DDT (1-dodecanethiol) functionalization of exfoliated MoS2 by using experimental and theoretical tools. For the functionalization of MoS2, DDT treatment was incorporated into the conventional NMP (N-methyl pyrrolidone) exfoliation procedure. Afterward, it has been demonstrated that the functionalization process is successful through optical, morphological and theoretical analysis. The D, G and 2LA peaks seen in the Raman spectrum of exfoliated NMP-MoS2 particles, indicate the formation of graphitic species on MoS2 sheets. In addition, as the DDT ratio increases, the vacant sites on MoS2 sheets diminish. Moreover, at an optimized ratio of DDT-NMP, the maximum number of graphitic quantum dots (GQDs) is observed on MoS2 nanosheets. Specifically, the STEM and AFM data confirm that GQDs reside on the MoS2 nano-sheets and also that the particle size of the DDT-MoS2 is mostly fixed, while the NMP-MoS2 show many smaller and distributed sizes. The comparison of PL intensities of the NMP-MoS2 and DDT-MoS2 samples states a 10-fold increment is visible, and a 60-fold increment in NIR region photoluminescent properties. Moreover, our results lay out understanding and perceptions on the surface and edge chemistry of exfoliated MoS2 and open up more opportunities for MoS2 and GQD particles with broader applications.