Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
22 results
Search Results
Article Ferroelectric to Relaxor Crossover in Zr-Doped BaTiO3-Based Ceramics and Its Consequences for the Electrocaloric Effect(Royal Soc Chemistry, 2025) Akkasoglu, Oguz; Karakaya, Merve; Novak, Nikola; Fulanovic, Lovro; Adem, UmutNa0.5Bi0.5TiO3 (NBT)-substituted BaTiO3 (BT)-rich solid solutions demonstrate significant electrocaloric effects owing to the first-order nature of their ferroelectric phase transition. However, their narrow phase transition range and relatively high transition temperature limit their suitability for electrocaloric cooling applications. To address these issues, we have investigated the impact of Zr-substitution (0-5 mol%) at the B-site on the phase transition behaviour of 0.7BT-0.3NBT solid solution. Our findings indicate that Zr-substitution strongly decreases the tetragonality and the Curie temperature of the samples. All samples exhibit relaxor-like characteristics, following the Vogel-Fulcher approach. However, at low Zr doping (0-3 mol%), a spontaneous transition into the ferroelectric phase is also observed on cooling from high temperatures. At higher Zr doping (4-5 mol%), the transition into the ferroelectric phase disappears and the sample presents canonical relaxor behaviour. The samples with canonical relaxor behaviour (4-5 mol% Zr) feature wider temperature ranges where a significant electrocaloric response is sustained, which yielded a large Tspan of similar to 45 degrees C for the 4% Zr-doped sample where a Delta T value of 0.77 K was maintained.Article Benzoxazine-Linked Porous Organic Networks for Effective Iodine Capture(Royal Soc Chemistry, 2025) Canturk, Batu Sercan; Erdogmus, Mustafa; Gecalp, Yasmin; Sahin, Hasan; Buyukcakir, OnurThis study presents, for the first time, the investigation of a benzoxazine-linked porous organic network (BPON) for iodine capture. BPON was synthesized through the Mannich condensation of paraformaldehyde, melamine, and phloroglucinol. The porous structure and heteroatom-rich skeleton of BPON make it a promising adsorbent platform for iodine capture. BPON demonstrated an effective iodine capture capability in the vapour phase (3.32 g g-1) and an impressive uptake capacity in the aqueous phase (2.80 g g-1 capacity, 90.4% removal efficiency in 12 hours). To investigate the effect of curing on iodine capture, BPON was thermally cured to prepare thermally cured benzoxazine-linked porous organic networks (cBPONs) at three different temperatures: 200, 250, and 300 degrees C. cBPONs demonstrated an iodine capture capacity of up to 2.20 g g-1 and 1.67 g g-1 for vapour and aqueous phases, respectively. The iodine capture mechanism of BPON was investigated using various ex situ analyses, including Fourier transform infrared (FT-IR), Raman spectra, and X-ray photoelectron spectra (XPS). Structural analysis and theoretical calculations indicated the formation of a charge-transfer complex upon iodine capture, leading to the generation of polyiodide species. This study demonstrates the potential of BPONs for iodine capture and paves the way for developing new polymeric adsorbents for capturing iodine from air and water.Article A Comparative Study on Hydroxyl and Ether Functionalized Ionic Liquid Additives for Defect Passivation and Stability in Perovskite Solar Cells(Royal Soc Chemistry, 2025) Siyahjani Gültekin, S.; Turgut, S.B.; Ozdemir, Saliha; Gültekin, B.; Varlikli, C.This study systematically investigates the effects of two ionic liquid (IL) additives, 2-(2-methoxyethoxy)-N,N-bis(2-(2-methoxyethoxy)ethyl)-N-methylethanaminium iodide (EtAI) and 2-hydroxy-N,N-bis(2-hydroxyethyl)-N-methylethanaminium iodide (HOAI), on the structural, morphological, optical, and photovoltaic properties of triple-cation perovskite thin films. FT-IR, XRD, XPS, SEM, and AFM analyses were employed to characterize additive-induced modifications, while UV-Vis, PL, and TRPL measurements were utilized to evaluate their optical properties. SEM and AFM results reveal that the hydroxyl (-OH) groups in HOAI and etheric groups in EtAI significantly improve film morphology by enhancing grain size, reducing surface roughness, and refining grain boundaries, thereby promoting more efficient charge transport. Photovoltaic characterization revealed that the film with 3 mmol HOAI exhibited a maximum reverse-scan power conversion efficiency (PCE) of 17.65%, retaining approximately 85% of its initial efficiency after 1000 hours under ambient conditions. In contrast, the film with 1 mmol EtAI achieved a reverse-scan PCE of 17.17%, although higher EtAI concentrations adversely affected stability. These findings provide valuable insights into the interplay between additive chemistry and perovskite film quality, offering a promising route for improving the efficiency and long-term performance of perovskite solar cells. This record is sourced from MEDLINE/PubMed, a database of the U.S. National Library of MedicineArticle Creatinine-On Colorimetric Elisa-Based Serum Creatinine Detection in a Microfluidic Device(Royal Soc Chemistry, 2025) Karakuzu, Betul; Tekin, H. CumhurChronic kidney diseases (CKDs), which often end in kidney failure for many people around the world, have an important place in public health given that they also trigger other diseases. Therefore, the development of fast and cost-effective diagnostic technologies enables effective monitoring of patients and early diagnosis. Here, using the Enzyme-Linked Immunosorbent Assay (ELISA) principle, serum creatinine concentrations were determined using the developed lab-on-a-chip (LOC) platform. In this system, which was termed "creatinine-on-a-chip", colorimetric ELISA protocol was applied to determine creatinine levels in a microfluidic chip functionalized with creatinine-specific antibodies. Creatinine detection was performed by quantifying the absorbance difference between the detection and reference channels, normalized to the reference signal within the microfluidic chip. The detection signal intensity varied depending on the region selected along the microfluidic channel. The adsorption of the capture antibody used for surface functionalization, which was particularly more pronounced near the inlet region, played a critical role in the detection signal. These findings suggest that random selection of the detection area can lead to significant signal variability, and that careful selection of a well-characterized region is essential for improving detection performance. With this developed system, creatinine was detected with high sensitivity in the linear range of 1-20 mu g mL-1, both spiked in phosphate buffered saline (PBS) and fetal bovine serum (FBS). Using the creatinine-on-a-chip, serum creatinine analysis can be performed rapidly (similar to 15 min) in a cost-effective manner ($1.05 per test).Article Citation - WoS: 1Citation - Scopus: 1Understanding the Role of a Specific Microenvironment in Personal Exposure To Semi-Volatile Organic Compounds Using Silicone Wristbands(Royal Soc Chemistry, 2025) Akmermer, Zulfikar; Demirtepe, HaleAssessment of personal exposure to semi-volatile organic compounds was facilitated using silicone wristbands (SWBs), an easy-to-use sampler that reflects total inhalation and dermal exposure from all the microenvironments and the activities in which the user was involved. Hence, SWBs help understand exposure from various routes, activities, and microenvironments. Offices are critical microenvironments where workers spend one-third of their daily time on weekdays; hence exposure from offices should be more extensively studied. This study aimed to investigate the personal exposure of university personnel and elaborate on the contribution of the exposure due to the office air to their overall exposure using SWBs. One SWB was worn by the participant, and another was hung in their office. After seven days of sampling on the wrist, exposure to polycyclic aromatic hydrocarbons (PAHs) was found to be related to combustion activities at home or from open fire, whereas exposure to organophosphate esters and phthalates was suggested to originate from building materials, such as flooring materials and paints, and consumer products, e.g. mattresses and furniture. PAHs in the participants' offices were influenced by the transport of outdoor air and phthalates from the ceiling material. Then, we estimated the equivalent air concentrations using the SWBs sampled from the offices and previously developed sampling rates and partition coefficients. The estimated office air exposure contributions to total inhalation and dermal exposure were 83%, 51%, and 39% for fluorene, tri(n-butyl) phosphate, and tris(2-chloro isopropyl) phosphate, respectively. These findings were consistent with the statistical analysis of personal data. To conclude, this study highlighted the importance of specific microenvironments in our exposure to particular SVOCs, offering strategies for indoor air quality management and human health risk assessment.Article Citation - WoS: 3Citation - Scopus: 3A Novel MIP Electrochemical Sensor Based on a CuFe2O4NPs@rGO Nanocomposite and Its Application in Breast Milk Samples for the Determination of Fipronil(Royal Soc Chemistry, 2025) Njjar, Muath; Akturk, Ezgi Zekiye; Kaya, Ahmet; Onac, Canan; Akdogan, AbdullahBackground: fipronil, a widely utilized insecticide in agriculture, has been shown to have potential health implications as it can accumulate in the environment and affect human health. Electrochemical sensors, specifically those incorporating molecularly imprinted polymers (MIPs), provide an efficient way for the detection of fipronil because of their selectivity and specificity. The combination of CuFe2O4NPs and reduced graphene oxide (rGO) exhibits a synergistic effect that enhances sensitivity and selectivity. The composite's effective properties provide a robust platform for fipronil determination in various matrices. This study detected fipronil using an electrochemical sensor based on a glassy carbon electrode (GCE) modified with MIP@CuFe2O4NPs@rGO. Results: the synthesized MIP@CuFe2O4NPs@rGO material was characterized using various techniques such as Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (FESEM), X-ray diffraction (XRD) analysis, energy dispersive X-ray (EDX) analysis, Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS) analysis, and electrochemical impedance spectroscopy (EIS). The modified GCE showed enhanced electrochemical behavior for fipronil, as demonstrated by cyclic voltammetry (CV) and square wave voltammetry (SWV) techniques. Optimization of parameters such as pH, pyrrole concentration, and template concentration further improved sensor performance. The sensor exhibited a linear dynamic range of 1 to 6 nM, with a limit of detection (LOD) of 0.30 nM (S/N = 3) and a limit of quantification (LOQ) of 1.08 nM (S/N = 10), highlighting its sensitivity and reliability. The precision of the method was excellent, with a relative standard deviation of less than 4.0%. When applied to quantify fipronil in breast milk samples, the sensor showed high accuracy and precision, with recoveries ranging from 96.24% to 97.75%. Significance: the sensor offers several advantages, including high sensitivity, specificity, and accuracy. Its ability to detect fipronil in complex matrices such as breast milk highlights its potential for real-world applications in environmental and health monitoring. Overall, this research paves the way for the development of efficient, rapid and eco-friendly sensors for detecting pesticide residues in various environmental and biological samples.Article Pvc/Pan-immobilized H2TiO3 Adsorbent: a Tailored Titanium-Based Lithium-Ion Sieve for High-Performance Lithium Recovery(Royal Soc Chemistry, 2025) Recepoglu, Yasar Kemal; Ipek, Onur; Yuksel, AsliThe increasing demand for lithium, driven by the rapid development of electric vehicles and energy storage systems, has created a pressing need for efficient and sustainable lithium recovery technologies. Conventional methods often face challenges related to selectivity, environmental impact, and scalability, necessitating the development of alternative materials. In this study, a polyvinyl chloride/polyacrylonitrile (PVC/PAN)-immobilized titanium-based lithium-ion sieve (HTO) was synthesized for lithium recovery from aqueous media, including geothermal brine. The objective was to obtain a selective, reusable, and mechanically stable adsorbent suitable for industrial-scale applications. The synthesized PVC/PAN-HTO composite was characterized by FT-IR, BET, XRD, and SEM techniques. Batch adsorption studies showed that the optimum lithium recovery occurred at pH 12, with efficiencies of 98.7% in model lithium solutions and 91.6% in geothermal water using a 4 g L-1 adsorbent dosage. Adsorption kinetics followed a pseudo-second-order model, and the Langmuir isotherm provided the best fit, indicating monolayer adsorption with a maximum capacity of 5.79 mg g-1. Thermodynamic analysis confirmed that the adsorption process is spontaneous and exothermic. Reusability tests demonstrated stable performance over three adsorption-desorption cycles, confirming the potential of PVC/PAN-HTO for practical lithium extraction applications.Article Advanced Adsorptive Removal of Dimethyl Phthalate From Water Using a Tertiary Amine-Functionalized Polymeric Resin: Insights Into Experimental Design and Statistical Analysis(Royal Soc Chemistry, 2025) Turekkan, Kubranur; Recepoglu, Yasar Kemal; Ova Ozcan, Duygu; Arar, OzgurThis study investigates the effective removal of dimethyl phthalate (DMP) from aqueous solutions using Purolite Macronet MN100, a polymer-based adsorbent containing tertiary amine functional groups. A series of batch experiments was performed to assess the influence of resin dosage and solution pH, while adsorption kinetics were analyzed to determine the optimal contact time and the underlying rate-limiting mechanism. Equilibrium data were interpreted using adsorption isotherm models, and thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees) were calculated to evaluate the feasibility and spontaneity of the process. Additionally, the effect of common coexisting ions in wastewater (Na+, K+, Mn2+, Ca2+, Mg2+) on DMP removal was examined. The optimum removal efficiency (>97%) was achieved using 0.02 g of resin per 25 mL solution at pH 2-6, with equilibrium established within 300 minutes. The adsorption behavior was best described by the Langmuir isotherm, indicating monolayer adsorption with a maximum capacity of 463.37 mg g(-1). Mechanistic evaluation revealed that pi-pi interactions and hydrogen bonding were the dominant forces driving DMP adsorption. The presence of competing cations had minimal impact, demonstrating the adsorbent's strong selectivity toward DMP. Desorption studies showed complete DMP recovery using absolute ethanol (>99%), with >99% regeneration efficiency. Optimization using Central Composite Design (CCD) under Response Surface Methodology (RSM) produced a statistically robust model (R-2 = 0.98), consistent with the experimental results. Overall, Purolite MN100 proved to be a highly efficient, selective, and regenerable adsorbent suitable for DMP removal in wastewater treatment processes.Article Citation - WoS: 1Citation - Scopus: 1Phase-Dependent Optical, Photocatalytic and Capacitive Properties of Tungsten Oxide Nanowires(Royal Soc Chemistry, 2025) Kahraman, Zeynep; Gungor, Ahmet; Buldu-Akturk, Merve; Tan, Metin; Alp, Emre; Erdem, Emre; Genc, AzizTransition metal oxides hold great promise across a wide range of applications due to favorable properties such as high abundance, low toxicity, and excellent stability. Nanoengineering approaches are essential for controlling the structural, optical, and electronic properties of these materials, enabling the achievement of desired characteristics in a cost-effective and environmentally friendly manner. In this study, we synthesize stoichiometric (WO3) and sub-stoichiometric (WO3-x) tungsten oxide nanowires by controlling their phases and morphologies through the hydrothermal method. This approach allows us to systematically investigate the effects of different phases and oxygen vacancies on the optical properties, as well as on photocatalytic and supercapacitance applications. We use the photodegradation of RhB as a benchmark for photocatalytic activity under various experimental conditions, revealing that oxygen vacancies significantly influence photocatalytic behavior. For example, WO3-x nanowires adsorb/degrade a substantial amount of RhB within short durations under ambient conditions, where WO3 nanowires are mostly inactive. The addition of H2O2 enhances the photocatalytic performance of WO3 nanowires over 30 minutes, with even better results under low pH conditions with H2O2. This study also explores the phase-dependent electrochemical properties of WO3 and WO3-x nanowires, providing insights into their potential for improved supercapacitor performance by leveraging their complementary properties in symmetric and asymmetric configurations. WO3-x, with a higher density of oxygen vacancies and thinner structure, offers enhanced conductivity and increased active sites for charge storage, resulting in superior specific capacitance and charge retention.Article Citation - WoS: 7Citation - Scopus: 6Polymeric Biomaterials for Periodontal Tissue Engineering and Periodontitis(Royal Soc Chemistry, 2024) Yuruk, Gizem; Demir, Yagmur Damla; Vural, Sevra; Kehr, Nermin SedaThe periodontium is one of the most complex tissues in the body because its structure is formed by a hierarchical combination of soft and hard tissues. Due to its complex architecture, the treatment and regeneration of damaged periodontal tissue caused by diseases is still a challenge in biomedicine. The most common disease of the periodontium is periodontitis, which occurs when the periodontium becomes infected and inflamed as a bacterial biofilm forms in the mouth. Recently, various biocompatible biomaterials made of natural and synthetic polymers have been developed for periodontal tissue regeneration or treatment due to their superior properties such as controlled drug and bioactive molecule delivery, mimicking the 3D network of tissue, biocompatibility, antibacterial and mechanical properties. In particular, biomaterials designed for drug delivery, such as hydrogels, scaffolds, films, membranes, micro/nanoparticles and fibers, and additively manufactured biomaterials have undergone in vitro and in vivo testing to confirm their potential clinical utility in periodontal regeneration and periodontitis treatment. This review explores recent advances in the use of biomaterials for the prevention and/or treatment of periodontal regeneration and periodontitis. Specifically, it emphasizes advancements in drug/biomolecule delivery and the use of additively manufactured biomaterials for addressing periodontal issues.
- «
- 1 (current)
- 2
- 3
- »