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Bayrak Pehlivan, Ilknur
Alternative names
Publications (10 of 36) Show all publications
Niklasson, G., Qiu, Z., Bayrak Pehlivan, I. & Edvinsson, T. (2019). Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts. In: Functional Materials and Nanotechnologies (FM&NT 2018): . Paper presented at 12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia. Institute of Physics Publishing (IOPP), Article ID 012005.
Open this publication in new window or tab >>Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts
2019 (English)In: Functional Materials and Nanotechnologies (FM&NT 2018), Institute of Physics Publishing (IOPP), 2019, article id 012005Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Hydrogen production by water splitting using nanomaterials as electrocatalysts is a promising route enabling replacement of fossil fuels by renewable energy sources. In particular, the development of inexpensive non-noble metal-based catalysts is necessary in order to replace currently used expensive Pt-based catalysts. We report a detailed impedance spectroscopy study of Ni-Mo and Ni-Fe based electrocatalytic materials deposited onto porous and compact substrates with different conductivities. The results were interpreted by a critical comparison with equivalent circuit models. The reaction resistance displays a strong dependence on potential and a lower substrate dependence. The impedance behaviour can also provide information on the dominating reaction mechanism. An optimized Ni-Fe based catalyst showed very promising properties for applications in water electrolysis.

Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2019
Series
IOP Conference Series-Materials Science and Engineering, ISSN 1757-8981 ; 503:1
National Category
Engineering and Technology Physical Chemistry
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-369729 (URN)10.1088/1757-899X/503/1/012005 (DOI)000471150800005 ()
Conference
12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia
Funder
Swedish Research Council, VR-2016-03713Swedish Research Council, VR-2015-03814EU, Horizon 2020
Available from: 2018-12-17 Created: 2018-12-17 Last updated: 2019-08-01Bibliographically approved
Granqvist, C. G., Arvizu, M. A., Bayrak Pehlivan, I., Qu, H.-Y., Wen, R.-T. & Niklasson, G. A. (2018). Electrochromic materials and devices for energy efficiency and human comfort in buildings: A critical review. Electrochimica Acta, 259, 1170-1182
Open this publication in new window or tab >>Electrochromic materials and devices for energy efficiency and human comfort in buildings: A critical review
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2018 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 259, p. 1170-1182Article, review/survey (Refereed) Published
Abstract [en]

Electrochromic (EC) materials can be integrated in thin-film devices and used for modulating optical transmittance. The technology has recently been implemented in large-area glazing (windows and glass facades) in order to create buildings which combine energy efficiency with good indoor comfort. This critical review describes the basics of EC technology, provides a case study related to EC foils for glass lamination, and discusses a number of future aspects. Ample literature references are given with the object of providing an easy entrance to the burgeoning research field of electrochromics.

National Category
Materials Chemistry Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-350203 (URN)10.1016/j.electacta.2017.11.169 (DOI)000423968600129 ()
Available from: 2018-05-08 Created: 2018-05-08 Last updated: 2018-12-17
Granqvist, C. G., Bayrak Pehlivan, I. & Niklasson, G. A. (2018). Electrochromics on a roll: Web-coating and lamination for smart windows. Paper presented at 60th Annual Technical Conference of the Society-of-Vacuum-Coaters (SVC), APR 29-MAY 04, 2017, Providence, RI. Surface & Coatings Technology, 336, 133-138
Open this publication in new window or tab >>Electrochromics on a roll: Web-coating and lamination for smart windows
2018 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 336, p. 133-138Article in journal (Refereed) Published
Abstract [en]

Electrochromic devices can vary the throughput of solar energy and visible light in glazing for buildings, which are then able to combine improved energy efficiency with enhanced indoor comfort and convenience. The technology can be implemented in different ways; here the focus is on web-coated devices which can be delivered, on a roll or in the form of large sheets, as foil for glass lamination. The present paper introduces the technology, discusses web-coating versus in-line glass coating, mentions lamination, and touches on possibilities to combine electrochromism with other functionalities such as thermochromic control of solar energy transmittance. The purpose of the paper is to give a tutorial overview of a technology that is currently introduced in buildings.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE SA, 2018
Keywords
Web-coated electrochromic device, Electrolyte functionalization, Infrared blocking, Thermochromism
National Category
Materials Chemistry Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-348848 (URN)10.1016/j.surfcoat.2017.08.006 (DOI)000425478000021 ()
Conference
60th Annual Technical Conference of the Society-of-Vacuum-Coaters (SVC), APR 29-MAY 04, 2017, Providence, RI
Available from: 2018-04-20 Created: 2018-04-20 Last updated: 2018-12-17
Saygili, Y., Turren-Cruz, S.-H., Olthof, S., Saes, B. W., Bayrak Pehlivan, I., Saliba, M., . . . Tress, W. (2018). Planar Perovskite Solar Cells with High Open-CircuitVoltage Containing a Supramolecular Iron Complex as HoleTransport Material Dopant. ChemSusChem, 19, 1-9
Open this publication in new window or tab >>Planar Perovskite Solar Cells with High Open-CircuitVoltage Containing a Supramolecular Iron Complex as HoleTransport Material Dopant
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2018 (English)In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 19, p. 1-9Article in journal (Refereed) Published
Abstract [en]

n perovskite solar cells (PSCs), the most commonly used hole transport material (HTM) is spiro-OMeTAD, which is typically doped by metalorganic complexes, for example, based on Co, to improve charge transport properties and thereby enhance the photovoltaic performance of the device. In this study, we report a new hemicage-structured iron complex, 1,3,5-tris(5'-methyl-2,2'-bipyridin-5-yl)ethylbenzene Fe(III)-tris(bis(trifluoromethylsulfonyl)imide), as a p-type dopant for spiro-OMeTAD. The formal redox potential of this compound was measured as 1.29 V vs. the standard hydrogen electrode, which is slightly (20 mV) more positive than that of the commercial cobalt dopant FK209. Photoelectron spectroscopy measurements confirm that the iron complex acts as an efficient p-dopant, as evidenced in an increase of the spiro-OMeTAD work function. When fabricating planar PSCs with the HTM spiro-OMeTAD doped by 5 mol % of the iron complex, a power conversion efficiency of 19.5 % (AM 1.5G, 100 mW cm-2 ) is achieved, compared to 19.3 % for reference devices with FK209. Open circuit voltages exceeding 1.2 V at 1 sun and reaching 1.27 V at 3 suns indicate that recombination at the perovskite/HTM interface is low when employing this iron complex. This work contributes to recent endeavors to reduce recombination losses in perovskite solar cells.

National Category
Condensed Matter Physics Energy Systems
Identifiers
urn:nbn:se:uu:diva-369254 (URN)10.1002/cphc.201800032 (DOI)
Available from: 2018-12-11 Created: 2018-12-11 Last updated: 2019-02-13Bibliographically approved
Pati, P. B., Damas, G., Tian, L., Fernandes, D. L. A., Zhang, L., Bayrak Pehlivan, I., . . . Tian, H. (2017). An experimental and theoretical study of an efficient polymer nano-photocatalyst for hydrogen evolution. Energy & Environmental Science, 10(6), 1372-1376
Open this publication in new window or tab >>An experimental and theoretical study of an efficient polymer nano-photocatalyst for hydrogen evolution
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2017 (English)In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 10, no 6, p. 1372-1376Article in journal (Refereed) Published
Abstract [en]

In this work, we report a highly efficient organic polymer nano-photocatalyst for light driven proton reduction. The system renders an initial rate of hydrogen evolution up to 50 +/- 0.5 mmol g(-1) h(-1), which is the fastest rate among all other reported organic photocatalysts. We also experimentally and theoretically prove that the nitrogen centre of the benzothiadiazole unit plays a crucial role in the photocatalysis and that the Pdots structure holds a close to ideal geometry to enhance the photocatalysis.

Keywords
CATALYSTS; H-2; SYSTEM; ENVIRONMENTAL SCIENCES; CELLS; CONJUGATED POLYMERS; ENERGY & FUELS; ARTIFICIAL PHOTOSYNTHESIS; WATER; ENGINEERING, CHEMICAL; GENERATION; CHEMISTRY, MULTIDISCIPLINARY; VISIBLE-LIGHT
National Category
Polymer Chemistry Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-332949 (URN)10.1039/c7ee00751e (DOI)000403320300009 ()
Funder
Knut and Alice Wallenberg FoundationSwedish Energy AgencyÅForsk (Ångpanneföreningen's Foundation for Research and Development)Stiftelsen Olle Engkvist ByggmästareStandUp
Available from: 2017-11-02 Created: 2017-11-02 Last updated: 2018-09-06Bibliographically approved
Bayrak Pehlivan, I., Marsal, R., Pehlivan, E., Runnerstrom, E. L., Milliron, D. J., Granqvist, C.-G. & Niklasson, G. (2014). Electrochromic Devices with Polymer Electrolytes Functionalized by SiO2 and In2O3:Sn Nanoparticles: Rapid Coloration/Bleaching Dynamics and Strong Near-Infrared Absorption. Solar Energy Materials and Solar Cells, 126, 241-247
Open this publication in new window or tab >>Electrochromic Devices with Polymer Electrolytes Functionalized by SiO2 and In2O3:Sn Nanoparticles: Rapid Coloration/Bleaching Dynamics and Strong Near-Infrared Absorption
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2014 (English)In: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 126, p. 241-247Article in journal (Refereed) Published
National Category
Engineering and Technology Nano Technology
Identifiers
urn:nbn:se:uu:diva-284199 (URN)
Available from: 2016-04-15 Created: 2016-04-15 Last updated: 2018-08-30
Pehlivan, I. B., Marsal, R., Pehlivan, E., Runnerstrom, E. L., Milliron, D. J., Granqvist, C.-G. & Niklasson, G. A. (2014). Electrochromic Devices with Polymer Electrolytes Functionalized by SiO2 and In2O3:Sn Nanoparticles: Rapid Coloring/Bleaching Dynamics and Strong Near-Infrared Absorption. Paper presented at 10th International Meeting on Electrochromism (IME), Holland, MI, August 12-16, 2012. Solar Energy Materials and Solar Cells, 126, 241-247
Open this publication in new window or tab >>Electrochromic Devices with Polymer Electrolytes Functionalized by SiO2 and In2O3:Sn Nanoparticles: Rapid Coloring/Bleaching Dynamics and Strong Near-Infrared Absorption
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2014 (English)In: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 126, p. 241-247Article in journal (Refereed) Published
Abstract [en]

We studied the optical properties and coloring/bleaching dynamics of electrochromic devices based on tungsten oxide and nickel oxide and incorporating polymer electrolytes functionalized by adding about one percent of nanoparticles of SiO2 (fumed silica) or In2O3:Sn. SiO2 improved the coloring/bleaching dynamics and In2O3:Sn quenched the near-infrared transmittance. Both of these effects can be important in electrochromic smart windows, and our results point at the advantage of a polymer laminated construction over a monolithic one.

National Category
Nano Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-204448 (URN)10.1016/j.solmat.2013.06.010 (DOI)000338395100035 ()
Conference
10th International Meeting on Electrochromism (IME), Holland, MI, August 12-16, 2012
Available from: 2013-08-05 Created: 2013-08-05 Last updated: 2017-12-06Bibliographically approved
Granqvist, C.-G., Bayrak Pehlivan, I., Ji, Y.-X. -., Li, S.-Y. & Niklasson, G. A. (2014). Electrochromics and thermochromics for energy efficient fenestration: Functionalities based on nanoparticles of In2O3:Sn and VO2. Thin Solid Films, 559, 2-8
Open this publication in new window or tab >>Electrochromics and thermochromics for energy efficient fenestration: Functionalities based on nanoparticles of In2O3:Sn and VO2
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2014 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 559, p. 2-8Article in journal (Refereed) Published
Abstract [en]

Windows incorporating electrochromic (EC) and thermochromic (TC) materials are of great interest for today's and tomorrow's buildings and can create energy efficiency jointly with indoor comfort. This paper summarizes several recent studies and shows that nanoparticles of transparent conducting oxides-specifically In2O3: Sn (ITO) and thermochromic VO2-can lead to desirable functionalities. We consider three examples: (i) the use of ITO nanoparticles in conventional polaronic EC devices in order to suppress near-infrared solar transmittance, (ii) performance limits for plasmonic EC devices based on ITO nanoparticles, and (iii) ITO-VO2-based nanocomposites combining low thermal emittance with TC properties. We also consider Mg doping of VO2 to enhance the luminous transmittance and Al2O3/VO2 double layers with improved durability. Both experimental and theoretical results are reported. (C) 2013 Elsevier B. V. All rights reserved.

Keywords
Electrochromism, Thermochromism, Smart window, Energy efficiency, Nanoparticles, Indium tin oxide, Vanadium dioxide
National Category
Physical Sciences Engineering and Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-227175 (URN)10.1016/j.tsf.2013.10.033 (DOI)000335443500002 ()
Projects
EU GRINDOOR
Funder
EU, FP7, Seventh Framework Programme, 267234
Available from: 2014-06-27 Created: 2014-06-24 Last updated: 2017-12-05Bibliographically approved
Bayrak Pehlivan, I., Granqvist, C.-G. & Niklasson, G. A. (2014). Ion conduction mechanism of nanocomposite polymer electrolytes comprised of polyethyleneimine–lithium bis(trifluoromethylsulfonyl)imide and silica. Electrochimica Acta, 119, 164-168
Open this publication in new window or tab >>Ion conduction mechanism of nanocomposite polymer electrolytes comprised of polyethyleneimine–lithium bis(trifluoromethylsulfonyl)imide and silica
2014 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 119, p. 164-168Article in journal (Refereed) Published
National Category
Nano Technology
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-204451 (URN)10.1016/j.electacta.2013.12.032 (DOI)000335877000023 ()
Available from: 2013-08-05 Created: 2013-08-05 Last updated: 2017-12-06Bibliographically approved
Granqvist, C.-G., Bayrak Pehlivan, I., Ji, Y.- . X., Li, S.-Y., Pehlivan, E., Marsal, R. & Niklasson, G. (2013). Electrochromics and Thermochromics for Energy Efficient Fenestration: New Applications Based on Transparent Conducting Nanoparticles. Materials Research Society Symposium Proceedings, 1558, 12 p., Article ID mrs13-1558-z09.
Open this publication in new window or tab >>Electrochromics and Thermochromics for Energy Efficient Fenestration: New Applications Based on Transparent Conducting Nanoparticles
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2013 (English)In: Materials Research Society Symposium Proceedings, ISSN 0272-9172, E-ISSN 1946-4274, Online Library, Vol. 1558, p. 12 p.-, article id mrs13-1558-z09Article in journal (Refereed) Published
National Category
Engineering and Technology Nano Technology
Identifiers
urn:nbn:se:uu:diva-285231 (URN)
Available from: 2016-04-19 Created: 2016-04-19 Last updated: 2018-08-30
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