Browsing by Author "Salman, Firat"

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Comparative of Mil101(Cr) and Nano-Mil101(cr) Electrode as an Electrochemical Hydrogen Peroxide Sensor
(Wiley-v C H verlag Gmbh, 2022) Salman, Firat; Kazici, Hilal Celik; Gulcan, Mehmet
Herein, an electrochemical sensor for the detection of H2O2 based on nafion glassy carbon electrode modified with MIL101(Cr) and nano-MIL101(Cr) are developed and its electrochemical characterizations analyzed by CV and CA. In comparison with the NGCE, MIL101/NGCE and nano-MIL101/NGCE, the nano-MIL101/NGCE showed a sharp redox peak specific to H2O2 was obtained in the phosphate-calibrated solution. nano-MIL101/NGCE exhibited good linear response in terms of the relationship between peak currents and concentrations as from 0 to 650 mu M (R-2=0.99), with a low limit of detection 3.8 mu M, high sensitivity 986 mu A mM(-1) cm(-2) and nano-MIL101/NGCE exhibited ideal repeatability, reproducibility, stability and the interference-free perception of H2O2.
Electrochemical Sensor Investigation of Carbon-Supported Pdcoag Multimetal Catalysts Using Sugar-Containing Beverages
(Springer, 2020) Salman, Firat; Kazici, Hilal C.; Kivrak, Hilal
Novel PdCoAg/C nanostructures were successfully synthesized by the polyol method in order to develop electrocatalysts, related to the glucose sensor performance of the high glycemic index in beverages. The characterization of this novel PdCoAg/C electrocatalyst was performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy equipped with energy dispersive X-ray. The characterization results revealed that electronic state of the PdCoAg/C electro-catalyst was modified by the addition of the third metal. The electrochemical performances of the sensor were investigated by cyclic voltammetry and differential pulse voltammetry. The prepared enzyme-free sensor exhibited excellent catalytic activity against glucose with a wide detection range (0.005 to 0.35 mmol center dot L-1), low limit of detection (0.003 mmol center dot L-1), high sensitivity (4156.34 mu A center dot mmol(-1) center dot L center dot cm(-2)), and long-term stability (10 days) because of the synergistic effect between the ternary metals. The glucose contents of several energy drinks, fruit juices, and carbonated beverages were analyzed using the novel PdCoAg/NGCE/C sensor system. These results indicate the feasibility for applications in the foods industry.
Pt-Ni Trimetallic Nanoparticles Anchored on Graphene Oxide: an Effective Catalyst for Ammonia-Borane Hydrolysis and Direct Electrooxidation of Ammonia-Borane in Alkaline Solution
(Pergamon-elsevier Science Ltd, 2024) Ahmed, Samal M. Mansur; Salman, Firat; Karatas, Yasar; Kazici, Hilal Celik; Gulcan, Mehmet
In this study, graphene oxide supported platin, nickel and cobalt trimetallic nanoparticles (PtNiCo@GO) were prepared by the impregnation/reduction method. The catalytic performances of PtNiCo@GO catalysts prepared with different atomic ratios were investigated for hydrogen production and electro-oxidation of ammonia-borane (AB). For hydrolysis of ammonia-borane, Pt0.8Ni0.1Co0.1@GO catalyst exhibited higher catalytic activity than Pt0.6Ni0.2Co0.2@GO, Pt0.4Ni0.3Co0.3@GO, and Pt0.2Ni0.4Co0.4@GO. The hydrogen generation rate and turnover frequency values were found to be 540 mL min- 1g- 1 and 42.8 min- 1 , respectively, in the experiment conducted at 35 degrees C, 0.5 mmol AB, and 50 mg Pt0.8Ni0.1Co0.1@GO catalyst. The activation parameters (Ea, Delta H # , and Delta S # ) in the catalytic hydrolysis of AB were obtained at 42.22 kJ/mol, 31.95 kJ/mol and-114.82 J/(mol x K), respectively. The effects of the PtNiCo@GO catalyst on AB electro-oxidation were made at a scanning rate of 100 mV/s in the potential range of- 1V/+1V against Ag/AgCl, and chronoamperometry measurements were made at constant potentials of- 0.2V, 0.1V and 0.4V. For cyclic voltammetry and chronoamperometry measurements, 5 mM [Fe(CN)6]3/4 (1 M KCl) redox probe and 1 M NaOH + 50 mM AB solution were used.
Simple Detection of Gluten in Commercial Gluten-Containing Samples With a Novel Nanoflower Electrosensor Made of Molybdenum Disulfide With Comparison of the Elisa Method
(Wiley, 2024) Salman, Firat; Zengin, Adem; Kazici, Hilal Celik
In this study, a new electrochemical sensor based on molybdenum disulfide (MoS2) nanoflowers/glassy carbon electrode (GCE was created for the sensitive detection of gluten. The prepared nanocatalysts were characterized using scanning electron microscopy with energy dispersive spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. The effects of the prepared nanocatalysts, pH value, and dropping amounts on the results were examined in detail. The electrochemical performance of the developed sensor (MoS2 nanoflowers/GCE) was then evaluated using differential pulse voltammetry, and the sensor was found to have significant electrochemical activity against gluten. A substantial linear connection was observed in the range of 0.5-100 ppm of gluten concentration under optimum experimental circumstances, and the detection limit between peak current and gluten concentration was determined as 1.16 ppm. The findings showed that the MoS2 nanoflowers/GCE gluten sensor has exceptional selectivity and stability. Finally, the generated electrochemical sensor was effectively utilized for gluten detection in commercial gluten-containing materials with a detection limit of 0.1652 ppm. Thus, the developed MoS2 nanoflowers/GCE sensor offers a potential method for the detection of other molecules and is a promising candidate for gluten detection in commercial samples.
Synthesis and Characterization of Fe3o4-Supported Metal-Organic Framework Mil-101(fe) for a Highly Selective and Sensitive Hydrogen Peroxide Electrochemical Sensor
(Springer Heidelberg, 2020) Salman, Firat; Zengin, Adem; Celik Kazici, Hilal
In this study, an electrochemical sensor for the quantification of hydrogen peroxide (H2O2) based on nafion glassy carbon electrode (NGCE) modified with MIL-101(Fe)@Fe(3)O(4)metal-organic frameworks (MOFs) was developed. Its electrochemical performance and surface analyses were examined with various techniques. The MIL-101(Fe)@Fe3O4/NGCE sensor exhibited a well-defined redox peak towards H(2)O(2)since the frameworks provide high electronic conductivity and easy mass transfer for target molecules. The parameters that affected the performance of the developed sensor were optimized. The proposed sensor showed a low detection limit (0.15 mu M) and relatively good sensitivity (68.8312 mu AmM-1 cm(-2)) according to the differential pulse voltammetry (DPV) method. Furthermore, the chronoamperometry (CA) method exhibited high sensitivity (556.5037 mu AmM-1 cm(-2)) but a relatively low detection limit (1.76 mu M), and the proposed sensor demonstrated excellent repeatability. Furthermore, the sensor was applied for the detection of H(2)O(2)in industrial samples.
Synthesis of 3d Sn Doped Sb2o3 Catalysts With Different Morphologies and Their Effects on the Electrocatalytic Hydrogen Evolution Reaction in Acidic Medium
(Elsevier Sci Ltd, 2021) Akinay, Yuksel; Kazici, Hilal Celik; Akkus, Ihsan Nuri; Salman, Firat
Recently, the design and synthesis of highly effective, abundant and low-cost catalysts to produce molecular hydrogen through the hydrogen evolution reaction (HER) have been studied in a wide range of pHs to replace Pt. In this work, 3D flower-like and rod-like pure Sb2O3 and Sn: Sb2O3 particles by using co-precipitation methods were efficiently synthesized for electro-catalytic energy conversion applications. The morphologies and structure of the synthesized catalysts were investigated extensively. Electrochemical studies were carried out to investigate the catalytic performance of 3D flower-like and rod-like Sn: Sb2O3 and pure Sb2O3 particles for hydrogen evolution reactions (HER) in acidic environments using 0.5 M H2SO4 electrolyte. Among the prepared particles, 3D rod-like Sn: Sb2O3 show excellent electro-catalytic hydrogen evolution reactions (HER) at 0.5 M H2SO4. Moreover, we have obtained the high stability of the electrodes during chronoamperometric studies (current v/s time) approximately 2000 s at constant potential.
Synthesis of Ferrocene Based Naphthoquinones and Its Application as Novel Non-Enzymatic Hydrogen Peroxide
(Wiley-v C H verlag Gmbh, 2020) Ertas, Nevroz Aslan; Kavak, Emrah; Salman, Firat; Kazici, Hilal Celik; Kivrak, Hilal; Kivrak, Arif
At present, a highly sensitive hydrogen peroxide (H2O2) sensor is fabricated by ferrocene based naphthaquinone derivatives as 2,3-Diferrocenyl-1,4-naphthoquinone and 2-bromo-3-ferrocenyl-1,4-naphthoquinone. These ferrocene based naphthaquinone derivatives are characterized by H-NMR and C-NMR. The electrochemical properties of these ferrocene based naphthaquinone are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) on modified glassy carbon electrode (GCE). The modified electrode with ferrocene based naphthaquinone derivatives exhibits an improved voltammetric response to the H2O2 redox reaction. 2-bromo-3-ferrocenyl-1,4-naphthoquinone show excellent non-enzymatic sensing ability towards H2O2 response with a detection limitation of 2.7 mu mol/L a wide detection range from 10 mu M to 400 mu M in H2O2 detection. The sensor also exhibits short response time (1 s) and good sensitivity of 71.4 mu A mM(-1) cm(-2) and stability. Furthermore, the DPV method exhibited very high sensitivity (18999 mu A mM(-1) cm(-2)) and low detection limit (0.66 mu M) compared to the CA method. Ferrocene based naphthaquinone derivative based sensors have a lower cost and high stability. Thus, this novel non-enzyme sensor has potential application in H2O2 detection.
Synthesis of Metal-Oxide Triple Nano Catalysts and Application To H2 Production and H2o2 Oxidation
(Springer, 2020) Kazici, Hilal Celik; Salman, Firat; Izgi, Mehmet Sait; Sahin, Omer
Magnesium oxide (MgO)-supported nanocatalysts are a highly insulating crystalline solid with a sodium chloride crystal structure and excellent properties including chemical inertness, high temperature stability and high thermal conductivity. Here, a ternary alloy catalyst of MgO-supported CoMoB was synthesized by means of a chemical reduction method using ethylene glycol solution. The prepared CoMoB/MgO catalysts were characterized using x-ray diffraction, scanning electron microscopy (SEM/EDX) and Fourier transform infrared spectroscopic analysis. The CoMoB/MgO nanocomposite served as the enabling platform for a range of applications including hydrogen production catalyst and hydrogen peroxide (H2O2) determination. It also showed a high hydrogen production rate (1000 mLgcat-1 min(-1)) and low activation energy (68.319 kJ mol(-1)) for the hydrolysis of ammonia borane. Additionally, the electro-oxidation performance of the CoMoB/MgO for H2O2 detection was studied by cyclic voltammetry and chronoamperometry. The CoMoB/MgO sensor demonstrated a wide linear range up to 10 mM with a detection limit of 3.3 mu M.
Synthesis of Pd-ni/C Bimetallic Materials and Their Application in Non-Enzymatic Hydrogen Peroxide Detection
(de Gruyter Open Ltd, 2017) Kazici, Hilal Celik; Salman, Firat; Kivrak, Hilal Demir
In this study, carbon based bimetallic materials (Pd-Ni/C) were synthesized by polyol method in order to increase the hydrogen peroxide reduction catalytic activity of Pd using Ni metal. Hydrogen peroxide reduction and sensing properties of the prepared catalysts were measured by electrochemical methods. As a result, we have established that the addition of Ni at different ratios to Pd has a considerable electrocatalytic effect on H2O2 reduction. This work provides a simple route for preparation of Pd-Ni catalysts to create a very active and sensible electrochemical sensor for H2O2 sensing.
Synthesis, Characterization, and Voltammetric Hydrogen Peroxide Sensing on Novel Monometallic (Ag, Co/Mwcnt) and Bimetallic (agco/Mwcnt) Alloy Nanoparticles
(Taylor & Francis inc, 2018) Kazici, Hilal Celik; Salman, Firat; Caglar, Aykut; Kivrak, Hilal; Aktas, Nahit
Multiwall carbon nanotube supported (MWCNT) Ag, Co, and Ag-Co alloy nanocatalysts were synthesized at varying metal loadings by borohydride reduction methods without stabilizers to obtain enhanced hydrogen peroxide sensitivity. The resulting materials were characterized employing Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). For electrochemical measurements carried out cyclic voltammetry (CV) and differential pulse voltammetry (DPV), glassy carbon electrode (GCE) was modified with Ag/MWCNT, Co/MWCNT, and Ag-Co/MWCNT alloy nanoparticles. Ag-Co/MWCNT/GCE exhibited the highest performance toward electrochemical oxidation of H2O2 in 0.1M phosphate buffered solution (PBS). Furthermore, the sensitivity and the limit of detection values for Ag-Co/MWCNT/GCE were obtained as 57.14 mu A cm(-2) mM(-1)and 0.74 mu M, respectively. However, the sensitivity values for Ag/MWCNT/GCE, and Co/MWCNT/GCE are 41.66 and 13.88 mu A cm(-2) mM(-1), respectively. The LOD values were predicted as 1.84 mu M for Ag/MWCNT/GCE and 3.3 mu M for Co/MWCNT/GCE.In addition, the interference experiment indicated that the Ag-Co/MWCNT alloy nanoparticles have good selectivity toward H2O2.