Profile URL: https://hdl.handle.net/20.500.13091/11671
Job Title:Prof. Dr.
Email Address:osahin@ktun.edu.tr
Main Affiliation:02.01. Department of Chemical Engineering
Status: Current Staff
ORCID:
0000-0001-6188-5517
0000-0001-6188-5517Scopus ID:
24766836200
24766836200YÖK Akademik: 3881AEAFD0E09131
Google Scholar:
IHxj1oQAAAAJ
IHxj1oQAAAAJWeb of Science ID:
V-4419-2017
V-4419-2017Name Variants:
Sahin Gokdogan, O. Şahin Gökdoğan, Ö.
24 results
Scholarly Output Search Results
Now showing 1 - 10 of 24
Master Thesis Voltametrik Yöntemle Ağır Metal Tayini(Konya Teknik Üniversitesi, 2021) Nadeesh, Abdullah; Şahin, Özlem GökdoğanHızlı sanayileşme ve kentleşme, çevrenin ağır metaller tarafından kirlenmesine neden olmuş ve bunların çevreye yayılma ve taşınma oranları büyük ölçüde hızlanmıştır. Ağır metallerin çevreye olumsuz etkileri giderek artmakta ve dünya çapında neden olduğu etkiler nedeniyle büyük bir sorun haline gelmektedir. Bu nedenle ağır metallerin doğru ve duyarlı tayini için basit ve hızlı yöntemler geliştirmek önemlidir. Bu yüksek lisans tez çalışmasında sentezlenen CuFe2O4-rGO kompoziti kullanılarak elektrokimyasal yöntemlerden biri olan voltametrik yöntemle ağır metal tayini amaçlanmıştır. CuFe2O4-rGO/GCE ile diferansiyel puls anodik sıyırma voltametrisi (DPASV) tekniği kullanılarak Zn+2 ve Cd+2 ağır metal iyonlarının tayini gerçekleştirilmiştir. Bu amaçla, elektrolit türü, elektrolit derişimi, elektrolit pH'ı, biriktirme potansiyeli ve biriktirme süresi gibi deneysel parametreler incelenerek, cevap akımını etkileyen parametrelerin optimum koşulları belirlenmiştir.Conference Object Sythesis and Chracterisation of Pd Based Catalysts for Sensor Application(2019) Yapıcı, Burak; Kıvrak, Hilal; Gökdoğan Şahin, ÖzlemHydrogen peroxide(H2O2) is one of the most appreciated analytes that is used in various areas such as food processes, bleaching of textiles and paper, phannaceuticai research, clinical laboratory, medical diagnostics, removal of inorganic and organic pollutants from wastewater, antiseptic and cleaning product, minerals processes and biochemistry (Ramazeni et. ali, 2017). On account of their tremendous catalytic activity to H2O2 and high electrical conductivity in comparison with many other bulk metals, birnetallic catalysts were commonly used for constructing nonenzymatic H2O2 sensors. Different techniques have been employed for the detennination of H2O2. Among them, electrochemical methods have attracted considerable interest due to their high sensitivity, fast response, low-cost and convenient operation (Davila et. ali, 2016). İn this study, highly active carbon nanotube supported birnetallic Pd based birnetallic catalysts have been synthesized for H2O2 sensors. After the preparation of electrodes; amperometric, voltametric and impedance measurements were performed by potentiostat device.Article Citation - WoS: 8Citation - Scopus: 8Fabrication of Novel Palladium-Platinum Based Graphene/Ito Electrodes and Third Metal Addition Effect Through the Glucose Electrooxidation(Elsevier Science Sa, 2022-08-01) Çağlar, Aykut; Hansu, Tülin Avcı; Şahin, Özlem; Kıvrak, Hilal; Avci Hansu, TulinGraphene was coated on Cu foil by chemical vapor deposition (CVD) method. The graphene on the Cu foil was modified by doping N. Then, N-doped graphene (G) was coated on several layers of indium tin oxide (ITO) electrodes. In addition, Pd, Pt, and M (Ag, V, Ni, Zn) metals were electroprecipitated on the graphene/indium tin oxide electrode by electrochemical technique. In this way, the glucose (C6H12O6) electrooxidation activities of these electrodes obtained from PdMPt-N doped graphane/indium tin oxide were investigated by cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) measurements. The obtained materials were characterized by SEM-EDX. Results revealed that the network of Pd, Pt, Ag, V, Ni, Zn and graphene was clearly visible from the SEM results. As a consequence, PdZnPt-N doped G/ITO showed the most effective C6H12O6 electrooxidation activity with a specific activity of 14.5 mA cm(-2), considerably above the literature's published values. In all electrochemical measurements, PdZnPt-N doped G/ITO exhibited the best electrocatalytic activity, stability, and resistance. PdZnPt-N doped G/ITO electrode is promising electrode for glucose electrooxidation.Article Citation - WoS: 12Citation - Scopus: 11Dendrimer Templated Synthesis of Carbon Nanotube Supported Pdau Catalyst and Its Application as Hydrogen Peroxide Sensor(WILEY-V C H VERLAG GMBH, 2019-05-22) Alal, Orhan; Çağlar, Aykut; Kıvrak, Hilal; Şahin, ÖzlemAt present, CNT supported catalysts were prepared by two different methods as NaBH4 reduction and dendrimer templated NaBH4 reduction method to observe the effect of preparation method on the sensitivity and activity of H2O2 reduction. Then, CNT supported PdxAuy bimetallic nanocatalysts having various atomic ratio were synthesized via novel dendrimer templated NaBH4 reduction method. The resulting materials were characterized employing XRD and TEM. Crystallite size of 10 %Pd0.7Au0.3/CNTdendrimer was obtained from XRD 17.1 nm and mean particle size obtained from TEM is about 15 nm. Moreover, the electrochemical behavior of these catalysts was characterized by cyclic voltammetry (CV) and chronoamperometry (CA) techniques. PdxAuy bimetallic nanocatalysts have excellent electrocatalytic properties and great potential for applications in electrochemical detection. The sensitivity and the limit of detection values for the prepared sensor with monometallic 10 % Pd/CNTdendrimer catalysts are 219.78 mu A mM(-1)cm(-2) and 2.6 mu M, respectively. However, the sensor constructed with 10 %Pd0.7Au0.3/CNTdendrimer modified electrode has a very high sensitivity of 316.89 mu A mM(-1) cm(-2) with a quick response time of 2 s and a wide linear range of 0.001-19.0 mM. In addition, the interference experiment indicated that the 10 % Pd0.7Au0.3/CNTdendrimer nanoparticles have good selectivity toward H2O2.Article Citation - WoS: 20Few-Layer Graphene Coated on Indium Tin Oxide Electrodes Prepared by Chemical Vapor Deposition and Their Enhanced Glucose Electrooxidation Activity(WILEY, 2019-07-29) Çağlar, Aykut; Ulaş, Berdan; Şahin, Özlem; Kıvrak, Hilal DemirAt present, few-layer graphene is deposited on copper (Cu) foil by chemical vapor deposition (CVD) method. Then, the few-layer graphenes produced on the Cu foil are coated onto the indium tin oxide (ITO) electrode to investigate their glucose electrooxidation activities. Hexane and hydrogen flow rate and deposition time parameters with CVD method are examined on different Cu foils. These electrodes are characterized by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Furthermore, glucose electrooxidation is examined with cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) measurements. One could note that the graphene network is clearly visible from SEM images. The deconvoluted XPS spectrum indicates that carbon appeared in the form of non-oxygenated ring C atoms for few-layer graphene. The few-layer graphene structure is confirmed by Raman analysis. Few-layer graphene/ITO produced at 5 sccm Hexane and 50 sccm hydrogen flow rate and 20minutes deposition time (G7/ITO) reveals the best electrode activity. The specific activity of G7/ITO electrode is obtained as 6.58mAcm(-2). According to CV, CA, and EIS results, G7/ITO electrode has high electrocatalytic activity, stability, and resistance in comparison with other electrodes.Article Citation - WoS: 42Citation - Scopus: 42A Complementary Study on Novel Pdauco Catalysts: Synthesis, Characterization, Direct Formic Acid Fuel Cell Application, and Exergy Analysis(PERGAMON-ELSEVIER SCIENCE LTD, 2018) Kıvrak, Hilal; Atbaş, Dilan; Alal, Orhan; Çögenli, M. Selim; Bayrakçeken, Ayşe; Mert, Suha Orçun; Şahin, Özlem; Yurtcan, Ayşe BayrakçekenAt present, Pd containing (10-40 wt%) multiwall carbon nanotube (MWCNT) supported Pd monometallic, Pd:Au bimetallic, and PdAuCo trimetallic catalysts are prepared via NaBH4 reduction method to examine their formic acid electrooxidation activities and direct formic acid fuel cell performances (DFAFCs) when used as anode catalysts. These catalysts are characterized by advanced analytical techniques as N-2 adsorption and desorption, XRD, SAXS, SEM-EDX, and TEM. Electronic state of Pd changes by the addition of Au and Co. Moreover, formic acid electrooxidation activities of these catalysts measured by CV indicates that particle size changes in wide range play a major role in the formic acid electrochemical oxidation activity, ascribed the strong structure sensitivity of formic acid electrooxidation reaction. PdAuCo (80:10:10)/MWCNT catalyst displays the most significant current density increase. On the other hand, lower CO stripping peak potential obtained for PdAuCo (80:10:10)/MWCNT catalyst, attributed to the awakening of the Pd-adsorbate bond strength down to its optimum value, which favors higher electrochemical activity. DFAFCs performance tests and exergy analysis reveal that fuel cell performances increase with the addition of Au and Co which can be attributed to synergetic effect. Furthermore, temperature strongly influences the performance of formic acid fuel cell. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Article Carbon Nanotube-Supported Bimetallic Core-Shell (m@pd/Cnt (m: Zn, Mn, Ag, Co, V, Ni)) Cathode Catalysts for H2o2 Fuel Cells(AMER CHEMICAL SOC, 2023-10-02) Yapıcı, Burak; Gökdoğan Şahin, Özlem; Sahin, Ozlem GokdoganM@Pd/CNT (M: Zn, Mn, Ag, Co, V, Ni) core-shell and Pd/CNT nanoparticles were prepared by sodium borohydride reduction and explored as cathode catalysts for the hydrogen peroxide reduction reaction. Electrochemical and physical characterization techniques are applied to explore the characteristics of the produced electrocatalysts. The cyclic voltammetry (CV) experiments show that Zn@Pd/CNT-modified electrodes have a current density of 273.2 mA cm(-2), which is 3.95 times higher than that of Pd/CNT. According to the chronoamperometric curves, Zn@Pd/CNT has the highest steady-state current density for the H2O2 electro-reduction process among the synthesized electrocatalysts. Moreover, electrochemical impedance spectroscopy (EIS) spectra confirmed the previous electrochemical results due to the lowest charge transfer resistance (35 Omega) with respect to other electrocatalysts.Conference Object Electrochemical Determination of Cadmium and Lead on Znf2o4/Rgo(2019) Muhammady, Shekiba; Atacan, Keziban; Gökdoğan Şahin, ÖzlemContamination of heavy metals (lead, cadmium, mercury, chromium, copper, nickel and zinc etc. possess serious problems to the environment and public health. Heavy metal ions are the main pollutant one of aqueous systems due to their solubility in water and non-biodegradable properties. Heavy metals taken in low concentrations can cause health problems. Serious and chronic illnesses are the worse effects associated with heavy metal ions poisoning even at low level exposure. (Kitt, et al., 2019). Stripping voltammetric methods are the most efficient electrochemical techniques for trace analysis due to their short response time, low cost, high sensitivity and selectivity for the detection of heavy metal ions in environmental samples .The performance of voltammetry is strongly influenced by the working electrode material. (Serran, et al., 2015). In this study, ZnFe2O4-rGO modified glassy carbon electrode has been used to detect lead (Pb (II)) and cadmium (Cd (II) in industrial wastewaters. In addition operational parameters including pH, deposition potential and time has been optimized.Article Citation - WoS: 1Citation - Scopus: 1Electrocatalytic Activity of Carbon Nanotube-Supported Pt-Based Bimetallic Catalysts for Borohydride Electro-Oxidation(SPRINGER, 2024-09-26) Uygun Batgi, Sibel; Yapıcı, Burak; Gökdoğan Şahin, Özlem; Batgi, Sibel Uygun; Sahin, Ozlem GokdoganOver the past ten years, sodium borohydride (NaBH4) has drawn attention due to the great usage of NaBH4 in energy systems. It can be directly oxidized in a direct borohydride fuel cell (DBFC) or it can produce hydrogen on demand. In this study, catalysts of Pt and PtAu supported on carbon nanotubes (CNT) were prepared using a NaBH4 reduction process to explore the electro-oxidation of NaBH4. The characterization of the catalysts has been performed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). The produced catalysts were about 4 nm in size and shared a similar particle shape. Cyclic voltammetry, linear sweep voltammetry, chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) measurements were evaluated for borohydride electro-oxidation. The experimental conditions were optimized by cyclic voltammetry for BH4- electro-oxidation on PtAu (70:30)/CNT. The EIS and CA results were in a good agreement with the cyclic voltammetry results in terms of electrocatalytic activity and stability of the PtAu/CNT, Au/CNT, and Pt/CNT catalysts. The improved performance of BH4- electro-oxidation can be ascribed to the complementary actions of CNT-supported Pt and Au particles, which improve catalyst contact and usage. These findings imply that the PtAu (70:30)/CNT catalyst is a viable anode catalyst for use in direct borohydride fuel cells.Conference Object Determination of Zinc and Cobalt by Voltammetric Method(2019) Nadeesh, Abdullah; Atacan, Keziban; Gökdoğan Şahin, ÖzlemMetal ions are biological toxicity to living organisms and accumulate in the food chain, which causes several health problems such as kidney deficiency, lung problems, hypertension and nervous system failure (Azmi et. all, 2017). Zinc (Zn) and cobalt (Co) are the metals that appear together in many real samples. These metals are among toxic metals of importance for environmental observation, food control and toxicology. Rapid, accurate and reliable techniques are required for the detection of these metals. Various methods can be used to detect heavy metals, including inductively coupled plasma-mass spectrometry (ICP-MS), inductively bound plasma atomic emission spectrometry (ICP AES) and atomic absorption spectrometry (AAS), and electrochemical methods. Among all commonly used techniques for the detection of heavy metals, electrochemical methods have advantages over spectrometric techniques. Electrochemical methods are cheap, highly accurate, easy to use, fast, portable and can be applied for field monitoring of environmental samples. Especially, the differential pulse anodic stripping voltammetry (DPASV) is a powerful and precise technique for the detection of heavy metals (Susom Dutta et. all, 2018). In this study, the CuFe2O4-rGO composite was synthesized and the glassy carbon electrode surface has been modified. The detection of Zn and Co were conducted by stripping voltammetry.
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Research Topics
Domains
Physical Sciences
Fields
EnergyChemistryEngineeringMaterials Science
Subfields
Renewable Energy, Sustainability and the EnvironmentElectrochemistryElectrical and Electronic EngineeringPolymers and Plastics
Specific Research Areas
Electrocatalysts for Energy Conversion
Electrochemical Analysis and Applications
Fuel Cells and Related Materials
Electrochemical sensors and biosensors
Conducting polymers and applications
Sustainable Development Goals
7AFFORDABLE AND CLEAN ENERGY
9
Research Products
14LIFE BELOW WATER
3
Research Products
6CLEAN WATER AND SANITATION
2
Research Products
3GOOD HEALTH AND WELL-BEING
2
Research Products
11SUSTAINABLE CITIES AND COMMUNITIES
1
Research Products
Documents
23
Citations
342
h-index
10
Documents
0
Citations
0
Publication Collaboration
| Affiliation Name | Count |
|---|---|
| Van Yüzüncü Yıl Üniversitesi | 13 |
| Konya Technical University | 12 |
| Selçuk University | 10 |
| Tarımsal Araştırmalar ve Politikalar Genel Müdürlüğü | 4 |
| Maden Tetkik ve Arama Genel Müdürlüğü | 4 |
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Data obtained from OpenAlex
| Journal | Count |
|---|---|
| INTERNATIONAL JOURNAL OF HYDROGEN ENERGY | 2 |
| ELECTROANALYSIS | 1 |
| ENERGY STORAGE | 1 |
| International Journal of Chemistry and Technology (IJCT) | 1 |
| INTERNATIONAL JOURNAL OF ENERGY RESEARCH | 1 |
Current Page: 1 / 3
Scholarly Output
24
Articles
11
Views / Downloads
42/245
Supervised MSc Theses
4
Supervised PhD Theses
0
WoS Citation Count
196
Scopus Citation Count
180
Patents
0
Projects
0
WoS Citations per Publication
8.17
Scopus Citations per Publication
7.50
Open Access Source
17
Supervised Theses
4
Scopus Quartile Distribution
Competency Cloud
