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2-etil-4-metil-1,3-tiyazol-5-karboksilik Asitin Korozyona Karşı İnhibisyon Etkisinin İncelenmesi
(2022) Mert, Mehmet Erman
Bu çalışmada, 2-etil-4-metil-1,3-tiyazol-5-karboksilik asitin (2E4MT5C) 0,5 M HCl çözeltisinde yumuşak çeliğin (MS) korozyon davranışına karşı inhibitör özellikleri elektrokimyasal ve teorik yöntemlerle araştırılmıştır. 7 günlük daldırma süresi boyunca 2E4MT5C içermeyen ve 5 mM 2E4MT5C içeren HCl çözeltilerinde elektrokimyasal impedans spektroskopi (EIS) ölçümleri ve polarizasyon eğrileri elde edildi. Farklı derişimlerde (0,5; 1; 3 ve 5 mM) 2E4MT5C içeren HCl çözeltilerinde 1 saatlik daldırma süresi için gerçekleştirilen EIS ölçümlerinden elde edilen veriler vasıtasıyla adsorpsiyon izotermi çizilerek, adsorpsiyon denge sabiti ve adsorpsiyon serbest enerjisi belirlendi. Moleküler yapı ile elektrokimyasal davranış arasında ilişki kurmak ve adsorpsiyon mekanizmasını araştırmak için deneysel sonuçlar teorik parametrelerle karşılaştırıldı. 1 saatlik daldırma süresi için elde edilen sonuçlara göre, MS için polarizasyon direnci değerleri 2E4MT5C yokluğunda 39 ?.cm2 ve mevcudiyetinde ise 195,3 ?.cm2 dir. 7 günlük daldırma süresi için elde edilen sonuçlara göre, MS için direnç değerleri 2E4MT5C yokluğunda 9,8 ?.cm2 ve mevcudiyetinde ise 38,3 ?.cm2 dir. Teorik olarak hesaplanan HOMO ve LUMO değerleri -6,89 eV ve -1,78 eV dir. Dipol moment 5,96 Debye olarak belirlenmiştir. Elde edilen sonuçlara göre 2E4MT5C'nin yumuşak çelik korozyonuna karşı etkin koruma sağladığı görülmüştür.
3D printed honeycomb transition metal decorated electrodes for hydrogen production
(Elsevier Sci Ltd, 2024) Mert, Mehmet Erman; Nazligul, Huseyin; Aydin, Emine Avsar; Mert, Basak Dogru
In this study, a PV-wind hybrid system was proposed as a power source for hydrogen production by alkaline electrolysis and it was examined MATLAB simulation for Adana region. In the alkaline electrolysis cell, lab-made 3D printed cathode substrates were used and its electrocatalytic activity was enhanced via electrodeposition of Ni, Cu and NiCu. The characterization was achieved via scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, contact angle measurement and X-Ray diffraction analysis. The electrochemical performance was determined via linear sweep voltammetry, cyclic voltammetry, Tafel polarization measurements, electrochemical impedance spectroscopy, chronoamperometry. Results showed that 3DNiCu electrode exhibited nodular shaped homogeneous surface characteristics and NiCu (111) and (200) crystalline morphology; it also demonstrated lower polarization resistance and higher current density during alkaline electrolysis procedure.
3D-Printed Antenna Design Using Graphene Filament and Copper Tape for High-Tech Air Components
(Sae Int, 2023) Aydin, Emine Avsar; Bicer, Mustafa Berkan; Mert, Mehmet Erman; Ozgur, Ceyla; Mert, Basak Dogru
Additive manufacturing (AM) technologies can produce lighter parts; reduce manual assembly processes; reduce the number of production steps; shorten the production cycle; significantly reduce material consumption; enable the production of prostheses, implants, and artificial organs; and produce end-user products since it is used in many sectors for many reasons; it has also started to be used widely, especially in the field of aerospace. In this study, polylactic acid (PLA) was preferred for the antenna substrate because it is environmentally friendly, easy to recycle, provides convenience in production design with a three-dimensional (3D) printer, and is less expensive compared to other available materials. Copper (Cu) tape and graphene filament were employed for the antenna patch component due to their benefits. The comprehensive comparative analysis between a full-wave model and a 3D-printed prototype of the antenna via the CST Microwave Studio program was demonstrated here. The surface characterization was achieved with scanning electron microscope and energy dispersive X-ray (SEM-EDX) and X-ray diffractometer (XRD) analysis. The homogeneous Cu and oxidized graphene (GO) were detected. The weight percent of carbon (C) and oxygen (O) on the graphene surface was 59.82% and 40.18%, respectively. The Cu (111), Cu (200), and Cu (220) peaks were determined on the Cu tape. The GO (011) peak was seen in the XRD spectra of the graphene sheet. The simulation and measurement comparisons are quite satisfactory. The antennas, produced using a conventional 3D printer, will be beneficial for various applications in aeronautics and astronautics.
A theoretical and experimental investigation using a multi-criteria decision-making approach to investigate the use of oak cupule biomass as a sustainable corrosion inhibitor for mild steel in acidic solution
(Elsevier Science SA, 2026) Sismanoglu, Sedef; Mert, Mehmet Erman; Mert, Basak Dogru; Abdulvahitoglu, Adnan
This study investigates adsorption mechanism and inhibition efficiency of oak cupule (OC) biomass on mild steel (MS) corrosion in an acidic medium through quantum chemical calculations and electrochemical analysis. The chemical composition of OC was characterized using FTIR-ATR, mass spectrometry, and UV-Vis spectroscopy. Electrochemical impedance spectroscopy was conducted at varying inhibitor concentrations, complemented by surface morphology analysis via SEM and contact angle measurements after 168 h of immersion. At 250 ppm, the inhibition efficiency reached 92.5 %, attributed to the presence of tannins and polyphenolic compounds. Adsorption followed the Langmuir isotherm, with an equilibrium constant of 2.36 L mg-1 and a Gibbs free energy change of-12.08 kJ mol-1. Contact angle measurements indicated increased hydrophobicity due to the formation of protective layer. Potential of zero charge (PZC) analysis confirmed electrostatic interactions
Ag Decorated NiCo Catalyst on Ni Foam Electrodes for Electrocatalytic Oxidation of Methanol
(Maik Nauka/Interperiodica/Springer, 2022) Mert, Mehmet Erman; Mert, Basak Dogru
In this study, nickel (Ni) and cobalt (Co) with various compositions were galvanostatically deposited on a nickel-based substrate (NiF); the convenient NiCo-electrode was decorated with silver nanoparticles (AgNPs), and was symbolized as NiF-NiCo(II)-Ag. For this purpose, chronopotentiometry technique was used. The prepared electrodes were examined as an anode for methanol electrooxidation in an alkaline solution containing 1 M methanol. The electrode characterization was carried out with field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD) techniques. The catalyst efficiency was determined by cyclic voltammetry (CV) and chronoamperometry (CA) analysis. The surface mapping revealed that Ag nanoparticles had a uniform surface dispersion and the lattice plane of the face-centered cubic (fcc) Ag peak was detected in XRD spectra. The electrochemical results revealed that Ni and Co deposition on NiF considerably improved the electrooxidation of methanol, and that the efficiency was further increased by enlarging the catalytic area and enhancing the charge transfer rate with the assistance of AgNPs decorating. The determined & UGamma; was 40.72 x 10(-6) mol g(-1) and D values were varied between 1.89 x 10(-12) and 2.96 x 10(-14) cm(2) s(-1). Furthermore, the current densities of NiF-NiCo(II)-Ag were almost equal for initial and final operation times of CA test for 50 000 s, almost 1.35 and 1.15 A g(-1), respectively. Before and after CA tests, CV results proved the long-term stability via repetitive cycles.
Analytical study on mild steel corrosion inhibition in acidic environment: DFT modeling and RSM optimization
(Elsevier Sci Ltd, 2025) Mert, Mehmet Erman; Gungor, Ceyla; Mert, Basak Dogru
This study investigates the corrosion inhibition potential of various heterocyclic compounds, including 1,3-Thiazole-4-carbothioamide, 4-aminopyrazolo[3,4-d]pyrimidine, pyrimidine-2-thiocarboxamide, 1,2,4-oxadiazole-3carbothioamide, 1H-imidazole-4-carbothioamide, 2-methyl-1,3-thiazole-4-carbothioamide, 4-aminothieno[2,3d]pyrimidine-2-thiol, and 2-isopropyl-4-methyl-1,3-thiazole-5-carboxylic acid, selected for their structural characteristics that make them effective in fuel applications. The presence of functional groups such as thiol, amide, carboxylic acid, imidazole, and thiazole in these compounds enhances their ability to adsorb onto metal surfaces, forming protective layers that significantly inhibit corrosion. These compounds were chosen not only for their strong interaction with metal substrates but also for their stability and durability under various environmental conditions, which are important for fuel systems. Density Functional Theory (DFT) calculations were performed to give structural insights, which are essential for understanding the corrosion inhibition mechanism of the examined compounds. The inhibition performance of these molecules were investigated in 0.5 M HCl via electrochemical impedance spectroscopy technique for mild steel (MS) containing various inhibitor concentrations (1;3 and 5 mM) and exposure times (1; 24 and 48 h). Particularly, the higher inhibition efficiency of compounds; 2-methyl-1,3-thiazole-4-carbothioamide and 4-aminothieno[2,3-d]pyrimidine-2-thiol from their structural and electronic properties. The variable inhibition efficiency observed among different compounds investigates the importance of methods Response Surface Methodology (RSM) for systematically analyzing concentration, time, and molecular structure interactions. The experimental results indicated that 2-methyl-1,3thiazole-4-carbothioamide and 4-aminothieno[2,3-d]pyrimidine-2-thiol exhibited significantly higher inhibition efficiency at a concentration of 5 mM and an exposure duration of 48 h, with inhibition efficiencies of 98.96 % and 98.66 % respectively.
Analytical study on mild steel corrosion inhibition in acidic environment: DFT modeling and RSM optimization
(Elsevier Sci Ltd, 2025) Mert, Mehmet Erman; Gungor, Ceyla; Mert, Basak Dogru
This study investigates the corrosion inhibition potential of various heterocyclic compounds, including 1,3-Thiazole-4-carbothioamide, 4-aminopyrazolo[3,4-d]pyrimidine, pyrimidine-2-thiocarboxamide, 1,2,4-oxadiazole-3carbothioamide, 1H-imidazole-4-carbothioamide, 2-methyl-1,3-thiazole-4-carbothioamide, 4-aminothieno[2,3d]pyrimidine-2-thiol, and 2-isopropyl-4-methyl-1,3-thiazole-5-carboxylic acid, selected for their structural characteristics that make them effective in fuel applications. The presence of functional groups such as thiol, amide, carboxylic acid, imidazole, and thiazole in these compounds enhances their ability to adsorb onto metal surfaces, forming protective layers that significantly inhibit corrosion. These compounds were chosen not only for their strong interaction with metal substrates but also for their stability and durability under various environmental conditions, which are important for fuel systems. Density Functional Theory (DFT) calculations were performed to give structural insights, which are essential for understanding the corrosion inhibition mechanism of the examined compounds. The inhibition performance of these molecules were investigated in 0.5 M HCl via electrochemical impedance spectroscopy technique for mild steel (MS) containing various inhibitor concentrations (1;3 and 5 mM) and exposure times (1; 24 and 48 h). Particularly, the higher inhibition efficiency of compounds; 2-methyl-1,3-thiazole-4-carbothioamide and 4-aminothieno[2,3-d]pyrimidine-2-thiol from their structural and electronic properties. The variable inhibition efficiency observed among different compounds investigates the importance of methods Response Surface Methodology (RSM) for systematically analyzing concentration, time, and molecular structure interactions. The experimental results indicated that 2-methyl-1,3thiazole-4-carbothioamide and 4-aminothieno[2,3-d]pyrimidine-2-thiol exhibited significantly higher inhibition efficiency at a concentration of 5 mM and an exposure duration of 48 h, with inhibition efficiencies of 98.96 % and 98.66 % respectively.
Bi2S3 and NiBiS3 electrocatalysts for alkaline hydrogen evolution reactions
(Pergamon-Elsevier Science Ltd, 2025) Aksaray, Goncagul; Mert, Mehmet Erman; Mert, Basak Dogru; Kardas, Gulfeza
Developing efficient and available catalysts is important for advancing hydrogen evolution reaction (HER) in alkaline water electrolysis, a promising technology for sustainable hydrogen production. This study reports the synthesis and electrochemical performance of Bi2S3 and NiBiS3 catalysts for the HER in alkaline water electrolysis. The catalysts were prepared via a hydrothermal method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The electrochemical behavior was evaluated using cyclic voltammetry (CV), cathodic current-potential curves (Tafel polarization), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) in 1 M KOH. The graphite electrode modified with NiBiS3 exhibited high catalytic activity. The significant increase in current density and decrease in polarization resistance from 3000 S2 cm2 (bare graphite) to 18.55 S2 cm2 were detected. The G/NiBiS3 electrode outperformed both the bare graphite and G/Bi2S3 electrodes, with the current density reaching-2.3 x 10-3 A cm-2 at-0.26 V. Morphological analysis revealed that Bi2S3 forms flower-like structures, while NiBiS3 exhibits a cauliflower-like morphology, providing increased active surface areas important for catalytic activity. The Tafel slope analysis confirmed the Volmer step as the rate-determining step in the HER mechanism, with the adsorbed hydrogen subsequently forming molecular hydrogen. Stability testing through CA demonstrated consistent catalytic activity, with the current density maintained at-0.014 A cm-2 over 75000 s. These findings demonstrate the potential of NiBiS3 as a reliable and effective catalyst for alkaline electrolysis-based sustainable hydrogen production.
Catalytic insights into methanol electrooxidation on Ni foam modified with Bi 2 O 3-Acetylene black-rGO: Synthesis, characterization, and performance evaluation
(Pergamon-Elsevier Science Ltd, 2024) Aksaray, Goncagul; Mert, Mehmet Erman; Mert, Basak Dogru; Karda, Gulfeza
The aim of this study was to develop efficient anode materials for direct methanol fuel cell applications. The Ni foam was modified with Bi 2 O 3 - acetylene black-rGO to increase catalytic activity toward methanol oxidation. The Bi 2 O 3 was synthesized via a straightforward green technique. The characterization was achieved by using Fourier transform infrared spectroscopy and X -Ray diffraction analysis. The transmission electron microscope and field emission scanning electron microscope was utilized to evaluate the surface properties of catalysts, and energy-dispersive X-ray spectroscopy were employed to determine the chemical composition. Bi 2 O 3 particles with diameters ranging from 15 to 75 nm were crystal structures in the (111), (220), (311), and (342) crystal planes. The performance of methanol electrooxidation in an alkaline medium was investigated using cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry techniques. The surface coverage of the redox species was 2.04 x 10 -5 mol g -1 , and the diffusion coefficient ranged between 8.02 x 10 -12 and 1.25 x 10 -13 cm 2 s - 1 . According to the obtained results, the Bi 2 O 3 - acetylene black-rGO modification enhanced the electrocatalytic activity of Ni foam against methanol oxidation in an alkaline medium.
Corrosion prevention of mild steel in acidic medium by 2-Pyrrolidi-n-1-yl-1,3-thiazole-5-carboxylic acid: Theoretical and experimental approach
(Elsevier, 2022) Karazehir, Tolga; Mert, Mehmet Erman; Mert, Basak Dogru
The inhibition efficiency of 2-Pyrrolidin-1-yl-1,3-thiazole-5-carboxylic acid (PTCA) against mild steel (MS) corrosion was investigated in acidic solution by using quantum chemical calculations based on Density Functional Theory (DFT) method and electrochemical measurements. The electrochemical impedance spectroscopy (EIS), potentiodynamic, potential zero charge (pzc) analysis and electrochemical noise (EN) measurements at various concentrations (from 0.1 to 10 mM) and immersion times were utilized in experimental part. The surface analysis was achieved scanning electron microscope (SEM) and contact angle measurements in the absence and presence of 10 mM PTCA. According to DFT results, PTCA exhibited 3.737 eV band gap and 8.130 Debye dipole moment which were a signal of potentially convenient corrosion inhibitor properties. PTCA has a remarkable corrosion inhibition capability to mild steel, which inhibited both anodic and cathodic corrosion rates, relying on it's physically adsorption on the metal solution interface and protection ability was increased with increasing PTCA concentration. The obtained adsorption equilibrium constant was 11.11 x 103 M-1 and calculated standard free energy of adsorption was -33.03 kJ mol-1. The determined activation energy values were 55.58 kJ mol-1 and 96.86 kJ mol-1 in 0.5 M HCl in the absence and presence of 10 mM PTCA, respectively. PTCA demonstrated a strong inhibition efficiency of 98.3%, after 168 h immersion, according to the EIS results. As a consequently, we recommend that PTCA is a convenient inhibitor in 0.1 M HCl for mild steel protection against corrosion.
Design and performance analysis of a PV-assisted alkaline electrolysis for hydrogen production: An experimental and theoretical study
(Elsevier Sci Ltd, 2024) Mert, Mehmet Erman; Edis, Cansu; Akyildiz, Senay; Demir, Beyza Nur; Nazligul, Huseyin; Gurdal, Yeliz; Mert, Basak Dogru
The PV assisted alkaline electrolysis cell was established for hydrogen generation. Lab-made AgNiCu modified nickel foam cathodes were used in this system. The characterization was achieved using field emission scanning electron microscopy, energy-dispersive X-ray and X-Ray diffraction analysis. The electrochemical performance was investigated via linear sweep voltammetry, cyclic voltammetry, Tafel polarization measurements and electrochemical impedance spectroscopy. The electrolysis potential and time depended efficiency was monitored. The structural theoretical analysis of the electrode surface and hydrogen evolution characteristics were also determined applying Density Functional Theory and Ab-initio Molecular Dynamics simulations which identified the role of Ag decoration and Cu incorporation on the surface against water and proton adsorptions. The modified cathode (AgNiCuF) improved the hydrogen production performance owing to lower hydrogen onset potential (-1.1 V) and charge transfer resistance (0.362 ohm at -1.5 V).
Detonation Parameters of the Pentaerythritol Tetranitrate and Some Structures Descriptors in Different Solvents - Computational Study
(2021) Hilal, Cihat; Önal, Müşerref; Mert, Mehmet Erman
Pentaerythritol tetranitrate (PETN, C5H8N4O12) is a relatively stable explosive nitrate ester molecule. It has been widely used in various military and public industrial productions. In this study, the solubility tendency of PETN in different organic solvents was investigated theoretically. Several physicochemical parameters of PETN such as density, detonation pressure, temperature, rate and products of detonation reaction were investigated using the B3LYP functional and basic set of polarization functions (d, p) containing 6-31G**. The obtained results have been compared with the literature values. Furthermore, the stability and reactivity of PETN in acetone, diethyl ether, ethanol, tetrahydrofuran, toluene and methylene chloride were examined. Results revealed toluene is a good solvent to increase the explosive properties of PETN.
DFT analysis of salicylideneaniline derivatives as corrosion inhibitors for mild steel
(2024) Mert, Mehmet Erman; Mert, Başak Doğru
Schiff bases are important in corrosion inhibition due to their ability to form stable complexes with metal ions and create protective layers on metal surfaces, thereby extending the lifespan of structural materials in various industrial applications. In this study the Salicylideneaniline and its derivatives were analyzed as corrosion inhibitor versus mild steel corrosion via DFT analysis. The eight molecules were chosen; salicylideneaniline, 2-(benzylideneamino)phenol, 4-(benzylideneamino)phenol, 2-phenyldiazenylphenol, 2-Phenylazo-4-methylphenol, 3-methyl-2-phenyldiazenyl phenol, 2-[(2-methylphenyl)diazenyl]phenol, 4-phenyldiazenylbenzene-1,3-diol), for this purpose. The Gaussian 03 program and the 6-311++G (d, p) basis set was used. Electronic properties such as the energy of the highest occupied molecular orbital (EHOMO), energy of the lowest unoccupied molecular orbital (ELUMO), energy gap (?E) between LUMO and HOMO, dipole moment, and charges on the backbone atoms, ESP were determined.
Electromagnetic and Chemical Analysis and Performance Comparison of Inset-fed Rectangular Microstrip Antennas
(Wiley-V C H Verlag Gmbh, 2023) Aydin, Emine Avsar; Bicer, Mustafa Berkan; Mert, Mehmet Erman; Mert, Basak Dogru
A simple method for creating lightweight and inexpensive microstrip patch antennas using reduced graphene oxide or acetylene black added epoxy resin was developed. The biggest goal in the method is optimizing the appropriate chemicals and production processes for producing the materials with the designed properties. Five examples of an inset-fed microstrip patch antenna operating at approximately 2.0-12.0 GHz were designed based on the antenna's basic analytical formula. Their models were created in a 3D electromagnetic simulation environment. After examining the performance results of the design, the appropriate design models were produced with both 3D printer technology and wet-chemical methods, and the experimental results were compared with the simulation results. The produced reduced graphene oxide or acetylene black added samples ' structure was illuminated with scanning electron microscope images, FTIR and Raman spectroscopy analysis. The measured S-11 characteristics of the antennas provide better performance as compared to the simulated results. The measured S-11 parameters for the two and three frequency bands fell substantially below -10 dB. As a result of the dielectric constants of the materials and the fabrication of the radiation plane, horizontal shifts were detected in the measurement outcomes.
Enhancing microstrip patch antenna performance through CNF-modified dielectric substrates and 3D printing techniques
(Emerald Group Publishing Ltd, 2025) Avsar Aydin, Emine; Seyedzavvar, Mirsadegh; Boga, Cem; Mert, Mehmet Erman; Dogru Mert, Basak
PurposeThis research investigates the impact of carbon nanofiber (CNF) incorporation on the dielectric properties, mechanical integrity and performance of microstrip patch antennas. This study examines how varying CNF concentrations affect key electromagnetic parameters like dielectric constant and loss tangent while assessing nanocomposite mechanical characteristics. Leveraging material modification and additive manufacturing, this study aims to enhance antenna performance, tunability and manufacturability.Design/methodology/approachAntenna substrates were fabricated using fused deposition modeling with acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) containing 0.05%-2% CNFs. Dielectric properties were analyzed, while scanning electron microscopy assessed surface homogeneity and CNF dispersion. Mechanical tests evaluated yield strength and toughness. Antennas were tested over 1-15 GHz, focusing on reflection coefficient (S11) and voltage standing wave ratio (VSWR).FindingsCNF-modified substrates exhibited tunable dielectric properties (1.98-2.21 dielectric constant). Scanning electron microscopy confirmed improved dispersion. ABS-based antennas with 2 Wt.% CNFs showed optimal S11 and VSWR in the 2-4 GHz range. While CNFs slightly reduced ABS yield strength, they enhanced toughness, demonstrating the potential of customized dielectric materials for high-performance antennas.Originality/valueThis study introduces a novel microstrip patch antenna fabrication method using fused deposition modeling with customized dielectric materials. Unlike conventional approaches, it enables precise dielectric tuning via controlled CNF incorporation. ABS and PC were chosen for their dielectric stability, mechanical strength and three-dimensional printing compatibility. Investigating CNF concentrations (0.05%-2%) provides insights into dielectric behavior, mechanical properties and processing constraints. Enhanced antenna performance, especially in the 2-4 GHz range, underscores material composition's impact. This scalable approach supports next-generation communication systems, including IoT, 5G and aerospace applications.
Environmentally Friendly Route for Synthesis of CuO Nanoparticles
(2023) Mert, Mehmet Erman; Mert, Başak Doğru
This study's objective is to synthesize copper (II) oxide (CuO) nanoparticles (NPs), which have numerous applications via eco-friendly route. In the study, employing curcuma herbal’s ethanolic extract in the synthesis route was thought to be a good alternative for the environmentally friendly synthesis of nanoparticles because there are many benefits associated with performing so. These advantages include being affordable, conveniently accessible, easy to extract, and less susceptible to contamination. The scanning electron microscopy (SEM), energy dispersive analysis (EDX), and transmission electron microscopy (TEM) analysis were used to examine the generated particles. Additionally, UV analysis and the determination of the zeta potential of CuO NPs were performed.
Experimental and computational study of a solar-powered electrolysis system with a SEPIC converter for green hydrogen production
(Pergamon-Elsevier Science Ltd, 2025) Nazligul, Huseyin; Mert, Mehmet Erman; Edis, Cansu; Demir, Beyza Nur; Gurdal, Yeliz; Elattar, Khaled M.; Mert, Basak Dogru
The study presents an integrated approach for sustainable hydrogen production by coupling a photovoltaic system with an alkaline electrolysis unit optimized for fluctuating solar conditions. The catalyst for the electrolysis system was NiCoMo-modified Ni foam, which was created using a two-stage galvanostatic procedure that involved Ni and Co deposition followed by Mo enrichment. Electrochemical tests such were used to verify the catalytic activity of alkaline electrolysis. The device produced 120.2 mL of hydrogen in 30 min at 3 V, with a Faradaic efficiency of around 93.6 %, showing suitable electrochemical efficiency. To ensure stable electrolysis operation, a SEPIC DC-DC converter was integrated into the system, managed by real-time maximum power point tracking algorithms-Particle Swarm Optimization, Genetic Algorithm, and Artificial Bee Colony-modeled using 2023 solar irradiance data from Adana, Turkey. The ABC algorithm demonstrated the fastest convergence performance. The SEPIC converter successfully stabilized the output voltage at 7.5 V despite daily and seasonal battery voltage variations, maintaining optimal catalyst operating conditions. In the theoretical part of the study, a Co and Mo-doped Ni surface was constructed, and water adsorption on the most stable surface was examined using Density Functional Theory (DFT). Computational examination of the electrical structure revealed that Mo atoms contribute significantly more to the alloy matrix than Ni and Co. DFT calculations found that the oxygen atom of the water molecule adsorbs on top of the Mo atom at an adsorption energy of -1.03 eV. Mo doping on the Ni(111) surface directly enhances the strength of water adsorption.
Green Synthesis of MoNi@TiO2 Nanocatalyst for Efficient Methanol Oxidation: Structural, Morphological, and Electrochemical Insights
(Wiley-VCH GmbH, 2025) Mert, Mehmet Erman; Mert, Basak Dogru; Elattar, Khaled M.
This study presents a novel, green approach for synthesizing MoNi@TiO2 core-shell nanocomposites as efficient electrocatalysts for direct methanol fuel cells (DMFCs). The use of Curcuma longa extract as a bioreduction and stabilizer agent for the synthesis of the nanocatalyst offers an eco-friendly alternative to traditional synthetic methods. Characterization confirms the successful formation of well-defined core-shell structures with a narrow size distribution and minimal organic residue. Remarkably, the presence of specific Mo/Ni oxide phases alongside anatase and rutile TiO2 in the shell verified unique catalytic properties. The developed Ni/MoNi@TiO2 electrocatalyst demonstrates promising electrocatalytic activity for methanol oxidation, comparable to or even surpassing established transition metal catalysts such as Pt-based catalysts, offering a promising alternative for DMFC applications. The concentration-dependent peak current density further highlights its potential for efficient DMFC operation. This work demonstrates the feasibility and advantages of using bio-inspired synthesis for developing sustainable and high-performance electrocatalysts for energy conversion applications.
Hydropower-Assisted Alkaline Electrolysis with NiCo-Modified Electrodes Produced by Additive Manufacturing for Enhanced Hydrogen Evolution Reaction
(Springer Heidelberg, 2025) Ekinci, Firat; Durhasan, Tahir; Mert, Mehmet Erman; Dogru Mert, Basak; Esenboga, Burak
In this study, micro hydropower assisted alkaline electrolysis system was investigated to meet small-scale energy needs in rural areas. One of the noteworthy aspects of the study is the modification of metal electrodes produced by additive manufacturing with high HER activity metals such as Ni and Co. Additive manufacturing offers benefits in terms of creating complex geometries, reducing material waste, and enabling rapid prototyping. The NiCo modification created through the galvanostatic method provides advantages in enhancing the electrochemical activity and stability of the electrodes, particularly regarding HER activity. The electrochemical activity of the hydrogen evolution reaction (HER) in 1 M KOH was investigated using linear sweep voltammetry, cyclic voltammetry and bulk electrolysis. Surface characterization was achieved through scanning electron microscopy, energy-dispersive X-ray analysis and X-Ray diffraction analysis. The water wettability characteristics of electrode surfaces were examined using contact angle measurements. The 3Dm NiCo electrode demonstrated higher catalytic performance, with a contact angle of 61 degrees compared to 92 degrees for 3Db, indicating improved wettability. XRD investigation revealed NiCo crystalline phases. At 3 V, compared to the unmodified 3Db electrode, the 3Dm NiCo electrode demonstrated a similar to 64% increase in hydrogen production (46.8 mL vs. 28.5 mL), confirming its enhanced HER performance. Long-term catalyst stability was determined over 180,000 s.
Investigation of Inhibition Performance of Phenytoin for Mild Steel Protection in HCl Solution: Electrochemical and Quantum Theoretical Approaches
(2022) Nazlıgül, Hüseyin; Gullu, Emre; Mert, Mehmet Erman; Mert, Başak Doğru
In this study, the application potential of the expired \"Epdantoin\" drug which includes phenytoin (EP) as the corrosion inhibitor was investigated. For this purpose, the electrochemical impedance spectroscopy measurements and polarization curves were obtained for 168 hours immersion period in 0.5 M HCl in the absence and presence of various concentration of EP. The experimental results were compared with quantum theoretical parameters in order to present adsorption behavior of EP. The adsorption equilibrium constant and Gibbs free energy were calculated as 5000 M-1 and -31,05 kj mol-1, respectively. The calculated HOMO and LUMO values were -6.67 eV and -0.72 eV, respectively. Results indicated that EP is a convenient candidate of corrosion inhibitor for mild steel in HCl medium.

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