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Öğe A comprehensive new study on the removal of Pb (II) from aqueous solution by sirnak coal-derived char(Taylor & Francis Ltd, 2021) Batur, Ebru; Baytar, Orhan; Kutluay, Sinan; Horoz, Sabit; Sahin, OmerIn this study, char was prepared from the Sirnak coal derivative as a new adsorbent by the pyrolysis process and successfully applied for Pb (II) removal. Prepared char adsorbent was characterized by analysis techniques such as thermogravimetric (TG)/differential thermogravimetric (DTG), iodine number, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) surface area. In the experimental design of the Pb (II) removal process, the relationship between operating factors (contact time, initial Pb (II) concentration and temperature) and process responses (adsorption capacity and removal efficiency) was modelled by applying response surface methodology (RSM). After that, the operating factors for the maximum adsorption capacity and removal efficiency of Pb (II) by char were optimized. In the removal of Pb (II), pseudo-first order and pseudo-second order kinetic models were used to determine the process mechanism. In addition, adsorption isotherm models such as Langmuir, Freundlich, and Dubinin-Radushkevich were applied to the equilibrium data to explain the adsorption mechanism between the adsorbent and adsorbate molecules. According to the results obtained, it was determined that kinetic and equilibrium isotherm data were better defined with pseudo-second order kinetic and Dubinin-Radushkevich isotherm models, respectively. The optimum values of the contact time, initial Pb (II) concentration, and temperature for maximum adsorption capacity (124.64 mg/g) and removal efficiency (92.35%) of Pb (II) were found as 150.00 min, 144.81 ppm, and 35.06 degrees C, respectively. This study indicated the application potential of Sirnak coal-derived char as a promising cost-effective adsorbent for the removal of heavy metals.Öğe A double-functional carbon material as a supercapacitor electrode and hydrogen production: Cu-doped tea factory waste catalyst(Springer, 2021) Ozarslan, S.; Atelge, M. R.; Kivrak, Hilal Demir; Horoz, Sabit; Yavuz, Cenk; Kaya, M.; Unalan, S.In the present study, our main aim is to show that the first synthesized metal-doped tea factory waste (TFW) catalyst can be used in both hydrogen production and supercapacitor application. In this context, TFW catalyst doped with copper (Cu) (TFW-Cu) was synthesized for methanolysis of NaBH4 and supercapacitor measurement. In the presence of four different parameters (metal type, metal amount, carbonization temperature, and carbonization time), methanolysis experiments of NaBH4 were performed and the catalyst with the maximum hydrogen production rate (HPR) was determined. As a result, it was determined that the 30% Cu-doped TFW (TFW-30%Cu) catalyst had a maximum HPR at a carbonization temperature of 300 degrees C and a carbonization time of 60 min compared to other substances. As a result of the methanolysis experiments performed in the presence of TFW-30%Cu catalyst, the maximum HPR and activation energy were determined as 9475 mL (min.g)(-1) and 13.02 kJ mol(-1), respectively. In supercapacitor application, the capacitance of the electrodes in the presence of TFW-30%Cu was calculated as 7-19.9 F.(g)(-1). Thus, it is expected that the synthesized catalyst will make a promising contribution in both energy storage and energy production areas-especially for distributed generation systems operating in national networks.Öğe A study on supercapacitor electrode material from trigonal planar and (N?B) dative bond stabilized tetrahedral boron-containing compounds(Springer, 2023) Kilic, Ahmet; Soylemez, Rahime; AkdemIr, Murat; Kivrak, Hilal DemIr; Kaya, Mustafa; Horoz, SabitThe present study has revealed that C40H38B2Cl2N4O6, a boron-containing compound, exhibits exceptional electrochemical performance when utilized as an electrode in supercapacitor applications. The specific capacitance values of C40H38B2Cl2N4O6 were found to be significantly higher than that of the traditional electrode material, C15H14BNO2 center dot HCl, in both KOH and Na2SO4 electrolyte solutions. In particular, when tested in KOH, the specific capacitance value of C40H38B2Cl2N4O6 was a staggering 3.74 times greater than that of C15H14BNO2 center dot HCl, demonstrating its exceptional energy storage capabilities. The superior performance of C40H38B2Cl2N4O6 can be attributed to its unique porous structure and high surface area, which enhances its ability to store charge. This research serves as a significant step towards the development of more advanced energy storage devices, and paves the way for C40H38B2Cl2N4O6 to be employed as a promising material in future supercapacitor applications.Öğe A study on the ligand-bound Mn(II) complex(Taylor & Francis Inc, 2020) Sahin, Omer; Kilinc, Dilek; Horoz, Sabit5 amino-2,4-dichlorophenol-3,5 ditertbuthylsalisylaldimine-Mn(II) complex was synthesized via the wet chemical method. The Mn(II) complex, characterized by its structural and optical properties, has been used as a sensitizer in a dye-sensitized solar cell structure by growing on TiO2 coated on fluorine-doped tin oxide conductive glass substrate. The power conversion efficiency of the TiO2/Mn (II) complex structure was calculated by current density (J) versus voltage (V) measurement. The calculated power conversion efficiency (eta%) of TiO2/Mn(II) complex is %1.44. The obtained result shows that this device can be used as a promising sensitizer in solar cell application.Öğe Absorption Induced by Mn Doping of ZnS for Improved Sensitized Quantum-Dot Solar Cells(2015-02-23) Horoz, Sabit; Dai, Qilin; Maloney, Scott; Yakami, Baichhabi; Pikal, Jon; Zhang, X.; Wang, J.; Wang, Wenyong; Tang, JinkeZnS quantum dots (QDs) have limited application potential in QD-sensitized solar cells because of their wide-band-gap, which does not allow absorption of sunlight in the visible and infrared regions. Introducing intermediate-energy levels in the QDs is one way to expand the absorption window into the visible region. We show that this effect is achieved in Mn-doped ZnS QDs. Mn-doped ZnS QDs are synthesized by laser ablation in water and solution-based methods. The structural, optical, and magnetic properties of the ZnS:Mn QDs are examined by x-ray diffraction (XRD), transmission electron microscope (TEM), photoluminescence (PL) emission, photoluminescence excitation (PLE), and magnetic susceptibility measurements. The average particle size of cubic phase ZnS:Mn estimated from the XRD and TEM is about 3 nm. The QDs show two PL peaks near 450 and 600 nm, which are attributed to the defect-related emission of ZnS and emission of Mn2? in a ZnS host, respectively. The PLE spectra exhibit near-band-edge absorption of ZnS at 350 nm and the absorption of Mn2? internal-energy levels around 468 nm. The latter absorption is due to the transitions of the 3d5 electronic states of Mn2? from the ground state 6A1 to excited states 4A1 and 4E and plays an important role in improving the absorption of the material in the visible region. ZnS:Mn QDs coated on Zn2SnO4 nanowires show greatly improved sensitization in the visible region as demonstrated by incident photon-to-electron conversion efficiency experiments. Our study also shows that the characteristics of solar-cell performance can be tuned with the Mn concentration.Öğe Al2O3 supported co-cu-b ( Co-Cu-B/Al2O3) catalyst for hydrogen generatıon by hydrolysıs of aqueous sodıum borohydrıde (NaBH4) solutıons(2019-07-10) Baytar, Orhan; İzgi, M. Sait; Horoz, Sabit; Şahin, Ömer; Nar, SerenIn this study, Al2O3 supported Co-Cu-B (Co-Cu-B/Al2O3) catalyst was synthesized by chemical impregnation and precipitation method to be used for catalytic hydrogen generation from NaBH4. Co-Cu-B/Al2O3 catalyst was synthesized at various ratios using Co-Cu-B/Al2O3 (5-20%). The effect of some parameters such as NaOH concentration (0- 7%), NaBH4 concentration (2.5-7.5%), catalyst amount (25-150 mg) and solution ambient temperature was investigated on the catalytic hydrolysis of NaBH4. The hydrogen generation rate was found as 2519 and 8962 mL*g-1 *min-1 for Co-Cu-B and Co-CuB/Al2O3 catalysts in NaBH4 hydrolysis, respectively. The order rate kinetics and activation energy for Co-Cu-B/Al2O3 catalyst were determined as 0.125 and 27 kJ*mol-1 , respectively. The obtained results suggest that Co-Cu-B/Al2O3 catalysts can be used for mobile applications of PEMFC systems.Öğe An efficient synergistic Co@CQDs catalyst for hydrogen production from the hydrolysis of NH3BH3(Springer, 2021) Onat, Erhan; Sahin, Omer; Izgi, Mehmet Sait; Horoz, SabitWe report the synthesis of carbon quantum dots supported-Co (Co@CQDs) catalyst and its catalytic activity. The synthesized Co@CQDs catalyst for the first time is used to obtain the maximum hydrogen production rate from hydrolysis of NH3BH3. The synthesized Co@CQDs catalyst indicates a compelling performance in the hydrogen production from the hydrolysis of NH3BH3. It is found that Co@CQDs with the loading of Co (10 wt%) indicates a hydrogen production rate of 18600.27 mL/min.g(cat) and low activation energy of 22.97 kJ mol(- 1). The current study demonstrates that CQDs are promising support for dispersing metal catalysts. Moreover, the synthesized Co@CQDs catalyst is characterized by X-ray diffraction, ultraviolet and visible light, photoluminescence, inductively coupled plasma optical emission spectrometry, and transmission electron microscope measurements.Öğe Biomass-based metal-free catalyst as a promising supercapacitor electrode for energy storage(Springer, 2022) Karakas, Duygu Elma; Akdemir, Murat; Imanova, Gunel T.; Kivrak, Hilal Demir; Horoz, Sabit; Kaya, MustafaIn present study, biomass doped H3PO4-Cat, named as STW-H3PO4-Cat, was used as a catalyst in the methanolysis of sodium borohydride (NaBH4). Spent tea waste (STW) was used for the first time in this study as biomass. The generated existing catalyst was also employed as an active supercapacitor material, demonstrating its dual function. To identify the most active catalyst in the methanolysis of sodium borohydride, the catalyst was functionalized in different H3PO4 concentrations (1-7 M), and different annealing temperatures (200-500 degrees C) and different annealing times (20-80 min). Optimum parameters were determined as 7 M H3PO4, 400 degrees C, and 40 min. The maximum hydrogen production (HPR) value and the activation energy (E-a) were determined as 76,640 mL min(-1) g cat(-1) and 12.03 kJ mol(-1). When the catalyst was investigated in terms of the supercapacitor, the electrode's capacitance at 1 A/g current intensity was found to be 158 F/g utilizing the charge-discharge curve. The catalyst with optimum conditions was structurally and morphologically characterized by Fourier Transform Infrared (FTIR), x-ray diffraction (XRD), and scanning electron microscope (SEM) measurements, respectively.Öğe Boron-containing compounds as a new candidate for supercapacitor electrode: simplified synthesis and structural identification properties(Elsevier Science Inc, 2023) Akdemir, Murat; Kivrak, Hilal Demir; Kilic, Ahmet; Beyazsakal, Levent; Kaya, Mustafa; Horoz, SabitIn this study, the performance of two boron-containing compounds, C14H14BNO2 center dot HCl (BCC1) and C38H38B2Cl2N4O4 (BCC2), as electrodes in supercapacitor applications was investigated in the presence of Na2SO4 and KOH electrolyte solutions. The specific capacitance values of the compounds were compared, and the results showed that trivalent boron (BCC1) exhibited higher specific capacitance values than tetravalent boron (BCC2) in both electrolyte solutions. In the presence of Na2SO4 electrolyte solution, the specific capacitance values of the trivalent (BCC1) and tetravalent (BCC2) boron compounds at a current density of 0.75 A/g were 135.21 and 94.87 F/g, respectively, while in the presence of KOH electrolyte, the specific capacitance values of the trivalent (BCC1) and tetravalent (BCC2) boron compounds at a current density of 0.75 A/g capacitance values were determined as 106.62 and 88.25 F/g, respectively. The cycling stability of the electrodes was also studied, and it was found that the capacitance of BCC1 electrode increased gradually over the cycles, while the capacitance of BCC2 electrode decreased. The study suggests that trivalent boron can be a promising material for supercapacitor applications. However, further research is required to optimize the cycling stability of the electrodes and understand the underlying mechanism.Öğe Catalytic activites of a biomaterial (sumac) catalyst in sodium borohyride methanolysis reactions(Elsevier, 2023) Karakas, Duygu Elma; Kaya, Mustafa; Horoz, SabitBiomass waste (sumac) in particular, is an excellent starting point for preparing carbon materials since it is abundant, inexpensive, environmentally beneficial, and renewable. Therefore, the aim of the present study is defatted sumac (DS)-hydrochloric acid (HCl)-cobalt (Co) (DS-HCl-Co) catalyst (it will be used as a catalyst for the first time) in the presence of low activation energy and high hydrogen production rate (HPR). The effect of different parameters such as amount of catalyst, concentration of NaBH4 and tem-perature on HPR value obtained as a result of NaBH4 methanolysis in the presence of DS-HCl-Co catalyst have been investigated. The synthesized catalysts are named DS-HCl (pure) and DS-HCl-Co (supported). While the HPR value (mL*gcat -1 *min -1) obtained as a result of the hydrolysis experiments carried out is 3516.16 for the DS-HCl catalyst, it is 8298.5 for the DS-HCl-Co catalyst. Thus, it should be noted that the HPR value increases approximately 2.36 times in the presence of support material. Our other motivation in the current study is to have low activation energy, which is an important factor that increases catalytic activity. Using the Arrhenius equation, the activation energy for the DS-HCl-Co catalyst is calculated as 31.67 kJ/mol and this value is lower than some reported values when compared to the literature. As a result, it can be said that the DS-HCl-Co catalyst is a unique, inexpensive, and ideal catalyst with high activity values for hydrogen production from alkali hydrides.(c) 2022 Elsevier B.V. All rights reserved.Öğe CdSe quantum dots synthesized by laser ablation in water and their photovoltaic applications(Applied Physics Letters, 2012-11-27) Horoz, Sabit; Dai, Qilin; Chen, Jiajun; Yakami, Baichhabi; Pikal, Jon; Wang, Wenyong; Tang, JinkeCdSe quantum dots (QDs) have been prepared by a facile and clean synthesis method––laser ablation in water. The structural and luminescent properties of the CdSe QDs have been investigated. The CdSe QDs of wurtzite crystal structure have an average particle size of about 5 nm. The QDs can be attached to ZnO nanowires making them ideal for applications in QD-sensitized nanowire solar cells. A uniqueness of the QDs attached to the ZnO nanowires by this laser ablation method is that they do not contain ligands, and the preparation avoids the complicated process of ligand exchange.Öğe Characterization and Photovoltaic Studies of Capped ZnS, CdS and Cd1-xZnxS (x=0.025) Nanoparticles(2017) Horoz, Sabit; İzgi, M Sait; Şahin, ÖmerCapped ZnS, Cd1-xZnxS (x=0.025) and CdS nanoparticles (NPs) were prepared by co-precipitation method using mercaptoethanol as capping agent. X-ray diffraction (XRD), photoluminescence (PL) and optical absorption measurements were performed to characterize their structural and optical properties. The lattice constants and average crystallite size of cubic phase of capped ZnS, Cd1-xZnxS and CdS NPs calculated from the XRD measurement. The quantum confinement effect on the NPs has been observed in the optical analysis. In addition, it is seen that the luminescence band of Cd1-xZnxS NPs enhances with the presence of Zn content. The incident photon to electron conversion efficiency (IPCE) and current density (J) - voltage (V) measurements exhibited that Capped Cd1-xZnxS (x=0.025) NPs coated on the TiO2 NWs has better performance compare to capped ZnS and CdS NPs on the TiO2 NWs. Capped Cd1-xZnxS (x=0.025) NPs can be promising material to improve the solar cell performanceÖğe Characterization of La-alloyed CdS QDs synthesized by the successive ionic layer adsorption and reaction (SILAR) technique(Springer, 2018) Ekinci, Arzu; Sahin, Omer; Horoz, SabitIn this present study, the photovoltaic, structural, elemental and optical properties of La-alloyed CdS quantum dots (QDs) synthesized at room temperature using the successive ionic layer adsorption and reaction (SILAR) technique were investigated for the first time. For La-alloyed CdS QDs with different La concentrations, incident photons to current efficiency (IPCE) was measured and the optimum La concentration giving the best solar cell efficiency was determined as 1%. Characterization procedures were then performed to determine the structural and optical properties of La-alloyed CdS QDs with 1% La. As a result, La-alloyed CdS QDs with 1% La have been proposed as promising materials for photovoltaic applications.Öğe Chemical bath deposition of Co-doped PbS thin films for solar cell application(Springer, 2020) Ekinci, Arzu; Sahin, Omer; Horoz, SabitCo-doped PbS thin films with different Co concentrations were synthesized by cost-effective chemical bath deposition technique. The main purpose of this study is to determine thin film which has the best photovoltaic efficiency by examining the photovoltaic properties of Co-doped PbS with different Co concentrations. To investigate photovoltaic properties, incident photon-to-current efficiency (IPCE) and current density (J)-voltage (V) measurements were performed. The second stage of our study is to characterize the properties of Co-doped PbS which has the best photovoltaic efficiency value. As a result of the characterization processes, the information about the crystal structure, crystallite size and energy band gap of Co-doped PbS was obtained. When the photovoltaic efficiency values obtained in the first stage of our study were taken into consideration, it was clearly observed that the Co-doped metal significantly improved the photovoltaic properties of the PbS.Öğe Co-La-B Katalizörünün Sentezlenmesi ve Yakıt Pilinde Kullanılması(2020) Horoz, Sabit; Ekinci, Arzu; Şahin, ÖmerBu çalışmada, bir hidrojen jeneratörü tasarlamak için Co-La-B katalizörü kullanılarak katalizör miktarı, NaOHkonsantrasyonu, NaBH4 konsantrasyonu ve çözelti sıcaklığı gibi parametrelerin hidrojen üretim hızı üzerindekietkisi incelenmiştir. Hidrojen üretim reaksiyonu için aktivasyon enerjisi 40,3 kJ mol-1 olarak hesaplanmıştır. CoLa-B katalizörünün varlığında elde edilen hidrojen üretim sistemi kullanarak, polimer elektrolit membran yakıthücresi (PEMFC) yığını çalıştırılmıştır. Yerinde üretilen hidrojen, bir PEM yakıt pilinde kullanılarak o yakıt pilineait verim hesaplanmıştır. Üretilen hidrojenin zamanla akım ve gerilim üzerindeki değişimleri incelenmiştir.Yerinde üretilen hidrojenin tek hücreli PEM yakıt pilinde kullanılması ile akım ve gerilim değerlerinden, 0,65W’lık bir güç değeri hesaplanmıştır. PEM yakıt pili uygulamasında güce ve ideal voltaja göre ortalama verimdeğerleri sırasıyla %62 ve %79 olarak bulunmuştur. Elde edilen sonuçlardan, Co-La-B katalizörünün PEM yakıtpili uygulamaları için ideal bir katalizör olduğu söylenebilir.Öğe Computational DFT calculations, photovoltaic properties and synthesis of (2R, 3S)-2, 3, 4-trihydroxybutoxy substituted phthalocyanines(Taylor & Francis Inc, 2020) Cabir, Beyza; Yildiko, Umit; Agirtas, Mehmet Salih; Horoz, SabitIn this study, 4-((2R, 3S)-2, 3, 4-trihydroxybutoxy) phthalonitrile was synthesized and characterized as starting material. This new starting material reacts with cobalt and copper metal salts to obtain metallophthalocyanine complexes. The electronic absorption of cobalt and copper phthalocyanine compounds in different concentrations of THF was investigated. In addition, the solubility and absorption of the compounds in different solvents were investigated. Density functional theory was also performed to support the relevant experimental results of the synthesized copper and cobalt center atomic compound. The photovoltaic performance of compounds was measured as current density-voltage (J-V).Öğe Controlled synthesis of Eu2+ and Eu3+ doped ZnS quantum dots and their photovoltaic and magnetic properties(2016-04) Horoz, Sabit; Yakami, Baichhabi; Poudyal, Uma; Pikal, Jon; Wang, Wenyong; Tang, JinkeEu-doped ZnS quantum dots (QDs) have been synthesized by wet-chemical method and found to form in zinc blende (cubic) structure. Both Eu2+ and Eu3+doped ZnS can be controllably synthesized. The Eu2+ doped ZnS QDs show broad photoluminescence emission peak around 512 nm, which is from the Eu2+ intra-ion transition of 4f6d1 – 4f7, while the Eu3+ doped samples exhibit narrow emission lines characteristic of transitions between the 4f levels. The investigation of the magnetic properties shows that the Eu3+ doped samples exhibit signs of ferromagnetism, on the other hand, Eu2+ doped samples are paramagnetic of Curie-Weiss type. The incident photon to electron conversion efficiency is increased with the Eu doping, which suggests the QD solar cell efficiency can be enhanced by Eu doping due to widened absorption windows. This is an attractive approach to utilize benign and environmentally friendly wide band gap ZnS QDs in solar cells.Öğe Cr Katkılı ZnS Kuantum Noktalarının Karakterizasyonu ve Fotovoltaik Özelliklerinin İncelenmesi(2018) Horoz, SabitSaf ve Cr katkılı ZnS kuantum nokta (QD) ‘larının yapısal, optiksel, manyetiksel ve fotovoltaik özelliklerioda sıcaklığında incelendi. Saf ve Cr katkılı ZnS QD’ler içerisinde herhangi bir karışık faz bulunmadığı veQD’lerin kübik yapıya sahip olduğu X-ışını kırınımı analizi ile doğrulandı. UV-visible absorpsiyon spektrumu ileCr katkılı QD’lere ait dalga boylarının saf ZnS QD’lere nazaran mavi kayma gösterdiği gözlemlendi. Baska birdeyişle, ZnS QD’lerin yasak enerji aralığı Cr ile katkılandığında artış gösterdiği tespit edildi. Manyetik histerezisölçümleri ile, Cr katkılı ZnS QD’lerin, süperparamanyetik davranış sergiledikleri gösterildi. Ayrıca, Saf ve Crkatkılı ZnS QD’lerin fotovoltaik özellikleri uyarılmış foton dönüşüm verimi (IPCE) ölçümleri ile incelendi. Eldeedilen sonuçlar, Cr katkılı ZnS QD’lerin güneş pillerinin performansını artırmak için duyarlaştırıcı olarak kullanılabileceğinigöstermektedir.Öğe Designing copper-doped zinc oxide nanoparticle by tobacco stem extract-mediated green synthesis for solar cell efficiency and photocatalytic degradation of methylene blue(Taylor & Francis Inc, 2024) Ekinci, Arzu; Sahin, Omer; Kutluay, Sinan; Horoz, Sabit; Canpolat, Gurbet; Cokyasa, Mine; Baytar, OrhanThis study presents the green synthesis of copper-doped zinc oxide (Cu-doped ZnO) nanoparticles using tobacco stem (TS) extract. The environmentally friendly synthesis method ensures distinct features, high efficiency, and applicability in various fields, particularly in solar cell technology and photocatalytic applications. ZnO nanostructures are investigated due to their unique properties, cost-effectiveness, and broad range of applications. The nanoparticles are synthesized with varying Cu concentrations, and their structural, morphological, and compositional characteristics are thoroughly analyzed. The Cu-doped ZnO nanoparticles exhibit improved properties, such as increased surface area and reduced particle size, attributed to the incorporation of Cu dopants. The green synthesis approach using TS extract serves as a stabilizing agent and avoids the toxicity associated with chemical methods. Characterization techniques including SEM, TEM, EDX, FTIR, and XRD confirm the successful synthesis of the nanoparticles. Photocatalytic degradation studies reveal that the 5% Cu-doped ZnO exhibits the highest photocatalytic activity against methylene blue, attributed to synergistic effects between Cu and ZnO, including oxygen vacancy and electron-hole pair recombination rate suppression. The photocatalytic mechanism involves the generation of superoxide and hydroxyl radicals, leading to methylene blue degradation. Furthermore, the Cu-doped ZnO nanoparticles demonstrate promising photovoltaic performance, with the optimal efficiency observed at a 5% Cu concentration. The study suggests that Cu-doped ZnO has the potential to enhance solar cell efficiency and could serve as an alternative material in solar cell applications. Future research should focus on refining Cu-doped ZnO for further improvements in solar energy conversion efficiency The successful synthesis of Cu-doped ZnO nanoparticles from tobacco stem extract suggests an environmentally friendly approach. The photocatalytic degradation studies demonstrate the superior activity of 5% Cu-doped ZnO against methylene blue, attributed to synergistic effects between Cu and ZnO. Cu-doped ZnO has the potential to significantly enhance solar cell efficiency. The demonstrated photocatalytic and photovoltaic activities of Cu-doped ZnO open avenues for further research in optimizing their performance for practical applications in solar energy technologies and sustainable energy production.Öğe Determination of the optimum Co concentration in Co:Sb2S3 thin films(Springer, 2018) Nar, Seren; Sahin, Omer; Horoz, SabitThis current study consists of two phases. In the first step, PbS, Sb2S3:Co(0.25%), Sb2S3:Co(0.5%), Sb2S3:Co(0.75%) and Sb2S3:Co (1%) and Sb2S3:Co (2.5%) thin films were successfully synthesized on Zn2SnO4 coated on FTO conductive glasses using chemical bath deposition method at room temperature. The photovoltaic properties of the synthesized thin films were examined by applying both incident photon-to-current efficiency (IPCE) and current density (J)-voltage (V) measurements. It was observed that Co:Sb2S3 thin films with different Co concentrations have higher IPCE (%) and power conversion efficiency (eta%) values higher than pure Sb2S3. Moreover, the Co concentration, which provides the best efficiency, was determined as 1% compared to other concentrations. In the second phase of the study; structural, elemental and optical properties of Sb2S3:Co (1%) thin film were investigated using X-ray diffraction, energy dispersive X-ray and optical absorption measurements, respectively. Consequently, it was clearly observed that the Co dopant affects particle size, energy band gap and power conversion efficiency of Sb2S3 thin films. In addition, our study suggests that Co:Sb2S3 thin films are promising materials that can be used in photovoltaic applications.
