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    Experimental and theoretical investigation for the spectrophotometric determination of thiabendazole in fruit samples
    (Elsevier, 2021) Tüzen, Mustafa; Altunay, Nail; Elik, Adil; Katin, Konstantin; Mogaddam, Mohammad RezaAfshar
    A simple, green, and effective vortex-assisted dispersive liquid–liquid microextraction method was developed for separation, preconcentration and spectrophotometric determination of thiabendazole in fruit samples. This method is based on zwitterionic deep eutectic solvent. Four different deep eutectic solvents were prepared by mixing betaine with 2-furoic acid, phenylacetic acid, mandelic acid, and glycolic acid at different molar ratio. Then these solvents were used for the extraction of thiabendazole. The interaction of acid-betaine complexes with TBZ molecule have been supported by theoretical investigation. Various analytical parameters such as pH, type and volume of deep eutectic solvent, dispersing solvent type, vortex time, and sample volume were studied and optimized. Tolerance limits of foreign species were also measured. The presented method provided a good linearity in the range of 0.4–150 µg L−1, low limit of detection (0.1 µg L−1), high preconcentration factor (1 5 0) and low relative standard deviation (below 2.5%). Presented method was successfully applied for extraction and determination of thiabendazole in fruit samples. The accuracy of method was confirmed by comparison with the standard addition method applied to the same fruit samples.
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    Interfacial charge transfer in g-C3N4/FeVO4/AgBr nanocomposite for efficient photodegradation of tetracycline antibiotic and Victoria blue dye
    (Academic Press Inc Elsevier Science, 2025) Dhull, Priya; Sonu, Sonu; Poonia, Komal; Raizada, Pankaj; Ahamad, Tansir; Kaya, Savas; Katin, Konstantin
    The study presents the fabrication and superior photoactivity of a ternary g-C3N4/FeVO4/AgBr heterojunction nanocomposite, synthesized via a chemical precipitation method for effective degradation of tetracycline (TC) and Victoria Blue (VB) dye under light illumination. The morphology and the crystal size of the synthesized nanocomposite were characterized by using FESEM and XRD and the calculated grain size (100.39 nm) is larger than the crystal size (48.14 nm) indicating strong interparticle bonding. The heterojunction design leverages dual S-scheme interfacial charge transfer, reducing electron-hole recombination as confirmed by optoelectronic and electrochemical techniques. The composite demonstrated superior performance, achieving 82.15% degradation of TC and 97.25% degradation of VB. The study highlights density functional theory (DFT) simulations and MottSchottky (MS) analysis, providing insight into the electronic structure, distribution of charge, and band alignments of the g-C3N4/FeVO4/AgBr nanocomposite. Electron spin resonance and radical scavenging experiments revealed holes and superoxide radicals as the primary species driving the degradation process. Furthermore, LCMS analysis provided insights into the degradation pathways, confirming the conversion of TC and VB into nontoxic byproducts. The photocatalytic stability was confirmed through five consecutive cycles with minimal disruption in both performance and morphology, demonstrating its potential for wastewater treatment applications. Consequently, this study illustrates how the collaborative interplay of dual S-scheme charge migration and silver plasmonic effects enhances the efficiency of the g-C3N4/FeVO4/AgBr nanocomposite, offering a novel and highly effective solution for the degradation of complex pollutants in environmental remediation.
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    Nano-hydroxyapatite as an efficient adsorbent for cadmium Removal: Experimental and theoretical insights
    (Elsevier, 2025) Billah, Rachid El Kaim; Simsek, Selcuk; Kaya, Savas; Katin, Konstantin; Essenni, Said; Jugade, Ravin; Shekhawat, Anita
    The presented work aims to investigate the cadmium adsorption on nano-crystalline hydroxyapatite (n-Hap). X ray diffraction (XRD), Fourier transform infra-red (FTIR), Scanning electron microscope (SEM), and Thermogravimetric analysis (TGA) techniques were applied to characterize the n-Hap. Adsorbent mass, pH value, and initial Cd2+concentration were varied to optimize the adsorption conditions. The best Langmuir adsorption isotherm provided equilibrium adsorption capacity of 52.79 mg/g. According to performed kinetic study, the surface reaction fits to the pseudo-second order model. Thermodynamic parameters of the adsorption (Delta G degrees, Delta H degrees and Delta S degrees ) were derived from the temperature dependence of the adsorption rates. We observed spontaneous endothermic chemisorption of Cd2+ ions. Density functional theory calculations confirmed the spontaneous chemisorption via formation of three Cd-O covalent bonds of about 2.1 & Aring; lengths.
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    Optimization of vortex-assisted ionic liquid dispersive liquid–liquid microextraction by experimental design prior to hydride generation atomic absorption spectrometry for determination of selenium species in food, beverage and water samples
    (Elsevier, 2021) Altunay, Nail; Elik, Adil; Katin, Konstantin
    We applied novel vortex-assisted ionic liquid dispersive liquid-liquid microextraction (VA-IL-DLLME) method to preconcentration and extraction of Se(IV) ions from water, beverage and food samples. The method was optimized using central composite design combined with the response surface analysis. After extraction, inorganic selenium species (total Se, Se(IV) and Se(VI)) were determined by hydride generation atomic absorption spectrometry. 1-n-Octyl-3-methylimidazolium bis(trifluoromethane)-sulfonamide [C8mim NTf2] and tetrahydrofuran were used as the extraction and dispersive solvents, respectively. Applied vortex assisted the extractant dispersion and accelerated the mass transfer process. Obtained optimum conditions for microextraction procedure are as follows: mass of [C8mim NTf2], pH, extraction time and THF volume should be equal to 85 mg, 6.8, 15 min and 730 μL, respectively. Under these conditions, we observed linear range, limit of detection and enrichment factor equal to 5−500ng L−1, 1.5 ng L−1 and 120, respectively. We also fount linear regression coefficients in the dependence between Absorbance and Se(IV) concentration: Absorbance = 0.0652 CSe(IV) + 0.0185. We added 200 μg kg−1 of Se(IV) to selected food samples and 100 ng L−1 of Se(IV) to selected waters and beverages. Relative standard deviations and recovery values were within the ranges of 2.4–3.5 % and 92.7÷103.4 %, respectively. The optimized VA-IL-DLLME method reported here provides high extraction efficiency, fast extraction and lower detection limit without a heating step than alternative microextraction methods. This method also requires environmental solvents for determination and preconcentration of trace Se species in the selected samples. In addition, the reported VA-IL-DLLME procedure is the first method which use [C8mim NTf2] as extraction solvent for the preconcentration and separation of Se(IV) ions.
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    Unveiling cutting-edge developments in defective BiOI nanomaterials: Precise manipulation and improved functionalities towards bolstered photocatalysis
    (Elsevier, 2025) Soni, Vatika; Malhotra, Monika; Singh, Archana; Khan, Aftab Aslam Parwaz; Kaya, Savas; Katin, Konstantin; Le, Quyet Van
    Defect engineering represents a paradigm shift in tailoring nanomaterials for enhanced catalytic performance across various applications. This manuscript succinctly highlights the significance of defect engineering in improving the catalytic performance of BiOI nanoparticles for multiple applications, particularly in photocatalysis. The photocatalytic process of BiOI semiconductor is intricately linked to its indirect bandgap and layered crystalline structure. By influencing the structural dynamics of its layered materials, defects contribute significantly to optimizing its catalytic performance. Fundamental insights into manipulating defects, including oxygen and iodine vacancies, bismuth defects, and synergistic dual defects, in BiOI are meticulously discussed. Advanced characterization techniques, spanning spectroscopy to microscopy, are explored for precise defect identification and quantification. The fragile van der Waals forces foster interactions between adjacent iodine atoms in BiOI, contributing to the overall structural stability. Understanding these structural intricacies lays a robust foundation for comprehending and exploring the exceptional physicochemical properties of twodimensional BiOI. The manuscript showcases BiOI potential in energy and environmental sectors, ranging from solar-driven H2 evolution to CO2 reduction and various harmful pollutant degradation. By unravelling the intricate interplay between defects and catalytic activity, this manuscript sets a new benchmark for tailored catalytic solutions. This manuscript offers a comprehensive overview of defect engineering in BiOI and charts a path towards sustainable and efficient photocatalytic systems. It underscores the imperative of meticulous defect control and innovation in addressing the pressing challenges of the energy and environmental landscape.