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    Öğe
    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
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    Öğe
    Lignocellulosic biomass based catalysis for hydrogen generation effect of pistachio shells and Raney nickel in NaBH4 hydrolysis
    (Nature Portfolio, 2025) Sismanoglu, Sedef; Abed, Luay Duraid Abed; Mert, Mehmet Erman; Dogru Mert, Basak
    Pistachio shell, which has a layered, porous structure, is a natural polymer composed of lignin, hemicellulose and cellulose. This study investigates the catalytic performance of a composite catalyst made from pistachio shell (PS) and Raney Ni (Ra-Ni) in sodium borohydride (NaBH4) hydrolysis for hydrogen production. Characterization techniques, ATR-FTIR, XRD, TGA, and FESEM-EDX, were utilized to analyze the morphology and structure of the catalyst. To assess catalytic performance, the rate of H2 generation was measured using a water displacement method at 298 K. A 0.15 g sample of catalyst, composed of 1:1 weight ratio of Ra-Ni and ball milled PS, was mixed with 100 mL of water and 1 wt% NaBH4. H2 production rate was monitored, providing insights into the catalyst's efficiency and effectiveness. Results demonstrated that the Ra-Ni and PS composite exhibited high catalytic activity, with H2 generation rates of 409 mL g- 1 catalyst after 450 s and 430 mL g- 1 catalyst after 900 s, respectively. Activation energy of Ra-Ni-PS was 23.30 kJ mol- 1. The produced composite has promising potential for H2 production applications via NaBH4 hydrolysis.
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    Öğe
    The facile production of Fe2O3-biochar electrocatalyst for methanol oxidation reaction
    (Pergamon-Elsevier Science Ltd, 2024) Mert, Mehmet Erman; Hani, Yahia Bani; Akalin, Mehmet Kuddusi; Sismanoglu, Sedef; Aksaray, Goncaguel; Mert, Basak Dogru; Kol, Hamiyet Sahin
    In this study, the facile-green method was applied for the production of electroactive composite anode material. For this purpose, biochar was produced via pyrolysis of Pinus nigra (PN) sawdust in a stainless-steel reactor at 300, 400 and 500 degrees C with 10 degrees C/min heating rate. The Fe2O3 particles were fabricated via the green synthesis method. The Fe2O3-biochar electrocatalyst was operated on Ni foam electrode and the potential application as an anode for methanol fuel cell was investigated in an alkaline medium. Field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller analysis (BET), and attenuated total reflectance Fourier transform infrared spectroscopy (FTIR/ATR) were used to characterize the morphology of the electrocatalyst samples. The electrochemical measurements of electrocatalyst samples were achieved via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and chronoamperometry (CA). The enlarged surface area of biochar enabled the formation of more electroactive sites for methanol electrooxidation and favorable structures of biochar could support to increased electrocatalytic activity of catalysts for methanol oxidation and produce favorable matrices for Fe2O3 loading. The obtained results demonstrate that the electrooxidation of methanol occurred at 0.36 V. The favorable structures of biochar acted as a support, enhancing the electrocatalytic activity of Fe2O3 for methanol oxidation. The electrocatalyst demonstrated remarkable activity with almost 4 A g-1 current density at 0.55 V. The Rct values were 0.73 omega and 0.45 omega at 0.55 V, for Ni foam and Ni foam/Fe2O3-biochar, respectively. Long-term measurements demonstrated that the Ni foam/Fe2O3-biochar catalysts was remarkably stable, with a 4 % difference in current before and after the CA analysis.