News

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Ulaş has defended his M.Sc. Thesis

Ulaş has defended his M.Sc. Thesis titled as "High Capacity Anode Materials for Lithium-Ion Batteries" succesfully. Congratulations!

26/01/2017

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Kıvanç has defended his M.Sc. Thesis

Kıvanç has defended his M.Sc. Thesis titled as "Investigation of Molybdenum Oxide as a Catalyst for Non-aqueous Lithium-Oxygen Batteries" succesfully. Congratulations!

03/01/2017



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Faruk has defended his M.Sc. Thesis

Faruk has defended his M.Sc. Thesis titled as "Ultrathin Titanium Dioxide Coatings on Carbon Nanotubes for Stable Lithium Oxygen Battery Cathodes" succesfully. Congratulations!

26/10/2016

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Our new paper is published in Chemistry - A European Journal

Our collaboration work with Dag group in Chemistry Department, was published in Chemistry - A European Journal titled as "Synthesis of Mesoporous Lithium Titanate Thin Films and Monoliths as an Anode Material for High Rate Lithium Ion-Batteries". In this study a novel synthesis method for nanostructured mesoporous LTO films was presented and electrochemical performance of these thin film anodes was demonstrated.

26/10/2016



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Our Group Members attended the ISE Meeting

EESL group members Mehmet, Faruk, Kivanc and Ulas attended the 67th Annual Meeting of the International Electrochemical Society held in The Hague, Netherlands. All presented posters about their research projects.

26/08/2016

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Research

Lithium-Oxygen Battery Cathodes

Lithium-oxygen battery discharges by the reaction of lithium ions with oxygen at the cathode (2 Li+ + O2 + 2 e- --> Li2O2(s) U=2.96 V), and lithium peroxide (Li2O2) is produced. Likewise, lithium peroxide is decomposed during charging and yield lithium ions and oxygen back, completing the cycle. To accommodate discharge and charge reactions, a conductive porous cathode is used. We aim to enhance the performance of lithium-oxygen battery using nanostructured porous cathodes, tailored for the specific needs of this system.

Li-O2 battery

Catalyst

Catalysts for Lithium-Oxygen Battery

The theoretical reversible potential for lithium-oxygen electrochemical reaction is 2.96 V. However, discharge reaction in lithium-oxygen battery occurs at a lower potential and charge reaction occurs at a higher potential in the real system, which in return decrease the energy efficiency of the battery. To reduce observed over-potentials, catalysts are employed in the lithium-oxygen battery cathode. Metal oxide nanoparticles are promising catalysts for this battery system and we're working towards developing cheap and efficient catalysts for lithium-oxygen battery.


High Capacity Anodes for Secondary Lithium Batteries

Graphite, the most common anode material for current lithium-ion batteries, can only provide limited amount of lithium ion storage which is no longer enough for many applications. In order to replace graphite anodes new materials with higher lithium ion storage capacity are needed. Silicon is one of the most promising materials for lithium ion storage, since it delivers 10 times more storage capacity than graphite does. However, the drastic volume expansion of silicon particles during lithiation results instability of the anode and the capacity of the anode decays via cycling. Our lab is developing new silicon composite materials with smart nanostructuring, that can help preserve the integrity of the anode during extensive cycling.

Silicon Anode
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People

EESL

October, 2016 - (From left to right) Top row: Ulas Kudu, Gamze Ulusoy Ghobadi, Mohammad Fathi Tovini, Kivanc Coban, Bhushan Patil. Bottom row: Cevriye Koz, Eda Yilmaz, Faruk Okur, Sunil Dutt.

Principle Investigator

Eda YILMAZ

Dr. Eda YILMAZ

Dr. Yilmaz graduated from Bilkent University, Chemistry Department in 2006. She got her Ph.D. from the same department under supervision of Prof. Dr. Sefik Suzer in 2011. She then moved to RIKEN institute in Japan for her postdoctoral studies where she worked in Dr. Hye Ryung Byon's laboratory. In RIKEN Dr. Yilmaz was engaged in a number of projects on lithium-oxygen batteries, some of which are developing cathode catalysts for lithium-oxygen battery, in-situ XRD characterization of lithium-oxygen electrochemical reaction, design and synthesis of ordered cathodes for lithium oxygen battery. Dr. Yilmaz's research interests include secondary lithium batteries, nanomaterial design and synthesis and spectroscopy.

Dr. Yilmaz's CV »

Group Members

Bhushan Patil

Dr. Bhushan Patil

Dr. Patil is currently a postdoctoral researcher in EESL. He finished his Ph.D. at Tokyo Institute of Technology in Tokyo, Japan under supervision of Prof. Dr. Takeo Ohsaka and Prof. Dr. Shigenori Fujikawa. His Ph.D. thesis is titled as "Study on direct electrochemistry of ascorbate oxidase". He is an expert in electrochemical characterization and nanomaterial synthesis. Dr. Patil is a recipient of TUBITAK 2216 scholarship for foreign researchers.

Gamze Ulusoy Ghobadi

Türkan Gamze Ulusoy Ghobadi

Gamze is a Ph.D. student of Material Science and Nanotechnology (MSN) program. Her research interests includes development of novel electrochemical materials for energy storage and conversion systems. Gamze is co-supervised by Dr. Ferdi Karadaş from Chemistry Department, Bilkent University.

Mohammed Fathi Tovini

Mohammed Fathi Tovini

Mohammed is a M.Sc. student of Material Science and Nanotechnology (MSN) program. His research interests include nanoparticle synthesis and sodium-oxygen batteries.

Ulas Kudu

Ulaş Kudu

Ulaş is a M.Sc. student of Material Science and Nanotechnology (MSN) program. His research interests include nanoparticle synthesis and high capacity lithium-ion battery anodes.

Alumni

Kivanc Coban

Kıvanç Çoban








Cevriye Koz

Dr. Cevriye Koz

Dr. Koz is currently a postdoctoral researcher at The University of Liverpool.

Faruk Okur

Faruk Okur

Sunil Dutt

Dr. Sunil Dutt

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Publications

Journal Publications

  1. Okur, F.; Eren, H.; Biyikli, N.; Yilmaz, E. "Conformal Ultrathin TiO2 Coatings on Carbon Nanotubes for Stable Li-O2 Battery Cathodes", Submitted.

  2. Mert Balci, F.; Kudu, O.U.; Yilmaz, E.; Dag, O.; "Synthesis of Mesoporous Lithium Titanate Thin Films and Monoliths as an Anode Material for High Rate Lithium Ion-Batteries", Chemistry - A European Journal, 2016, 22(52), 18873. DOI: 10.1002/chem.201604253.

  3. Mohamed, A.; Osman, T.A.; Toprak, M.S.; Muhammed, M.; Yilmaz, E.; Uheida, A. "Visible light photocatalytic reduction of Cr(VI) by surface modified CNT/titanium dioxide composites nanofibers", Journal of Molecular Catalysis A: Chemical, 2016, 424, 45. DOI: 10.1016/j.molcata.2016.08.010

  4. Susapto, H.H.; Kudu, O.U.; Garifullin, R.; Yilmaz, E.; Guler, M.O. "One-Dimensional Peptide Nanostructure Templated Growth of Iron Phosphate Nanostructures for Lithium-Ion Battery Cathodes", ACS Applied Materials and Interfaces, 2016, 8 (27), 17421, DOI: 10.1021/acsami.6b02528.

  5. Yilmaz, E.; Yogi, C.; Yamanaka, K.; Ohta, T.; Byon, H.R. "Promoting Formation of Noncrystalline Li2O2 in Li-O2 Battery with RuO2 Nanoparticles", Nano Letters, 2013, 13, 4679, DOI: 10.1021/nl4020952.

  6. Lim, H.; Yilmaz, E.; Byon, H.R. Real-Time XRD Studies of Li-O2 Electrochemical Reaction in Nonaqueous Lithium-Oxygen Battery", The Journal of Physical Chemistry Letters, 2012, 3, 3210, DOI: 10.1021/jz301453t.

  7. Yilmaz, E.; Sezen, H.; Suzer, S. Probing the charge build-up and dissipation on thin PMMA film surfaces at the molecular level by XPS", Angewandte Chemie International Edition, 2012, 51, 5488, DOI: 10.1002/anie.201201351.

  8. Majeski, M.W.; Pleticha, F.D.; Bolotin, I.L.; Hanley, L.; Yilmaz, E.; Suzer, S. Photoresponse of PbS Nanoparticle - Quaterthiophene Films Prepared by Gaseous Deposition as Probed by XPS", Journal of Vacuum Science and Technology A, 2012, 30, 04D109, DOI: 10.1116/1.4709386.

  9. Yilmaz, E.; Ertas, G.; Bengu, E.; Suzer, S. Photo-Patterning of PMMA films with Gold Nanoparticles: Diffusion of AuCl4- Ions", The Journal of Physical Chemistry C, 2010, 114, 18401, DOI: 10.1021/jp106672f.

  10. Yilmaz, E.; Suzer, S. Au nanoparticles in PMMA matrix: In situ synthesis and the effect of Au nanoparticles on PMMA conductivity", Applied Surface Science, 2010, 256, 6630, DOI: 10.1016/j.apsusc.2010.04.060.

  11. Ozkaraoglu, E.; Tunc, K.; Suzer, S. Preparation of Au and Au-Pt nanoparticles within PMMA matrix using UV and X-ray irradiation", Polymer, 2009, 50, 462, DOI: 10.1016/j.polymer.2008.12.008.

  12. Ozkaraoglu, E.; Tunc, I.; Suzer, S. X-ray induced reduction of Au and Pt ions on silicon substrates", Surface & Coatings Technology, 2007, 201, 8202, DOI: 10.1016/j.surfcoat.2006.07.264.

  13. Karadas, F.; Ertas, G.; Ozkaraoglu, E.; Suzer, S.; X-ray-induced production of gold nanoparticles on a SiO2/Si system and in a poly(methyl methacrylate) matrix", Langmuir, 2005, 21, 437, DOI: 10.1021/la0478604.

Conference Presentations

  1. Okur, F., Eren, H., Sagkal, S., Biyikli, N., Yilmaz, E., "Thin Film Coatings on Multiwalled Carbon Nanotubes for Lithium-Oxygen Battery Cathodes: Eliminating the Carbon Surface", Poster Presentation, ECS Conference on Electrochemical Energy Conversion and Storage with SOFC-XIV, July 26 - 31 2015, Glasgow, England.

  2. Yilmaz, E.,, Yogi, C., Yamanaka, K., Ohta, T., Byon, H.R. "Evaluation of Lithium-Oxygen Battery Performances using XANES Spectroscopy", Oral Presentation, 30th European Conference on Surface Science (ECOSS), August 31 - September 5 2014, Antalya, Turkey.

  3. Yilmaz, E.; Byon, H. R. "RuO2 Nanoparticles as Oxygen Evolution Catalysts for Li-O2 Battery Cathode", Oral Presentation, The 93rd Chemical Society of Japan Annual Meeting, March 22-25 2013, Kusatsu, JAPAN

  4. Yilmaz, E.; Byon, H. R. "RuO2 Nanoparticles as Oxygen Evolution Catalysts for Li-O2 Battery Cathode", Oral Presentation, The 53rd Battery Symposium in Japan, November 14-16 2012, Fukuoka, JAPAN

  5. Yilmaz, E.; Byon H. R. "Binder-free and Well-ordered Multi-walled Carbon Nanotube Electrode for Li-O2 Battery", Poster Presentation, The 16th International Meeting on Lithium Batteries, June 17-22 2012, Jeju, SOUTH KOREA

  6. Yilmaz, E.; Suzer, S. "UV Induced Synthesis and XPS Characterization of Gold Nanoparticle-PMMA Composites", Poster Presentation, AVS 57th International Symposium & Exhibition, October 17-22 2010, Albuquerque, New Mexico, USA

  7. Yilmaz, E.; Suzer, S. "Photo-patterning of PMMA Films with Gold Nanoparticles", Oral Presentation, 6th Nanoscience and Nanotechnology Conference, June 15-18 2010, Izmir, TURKEY

  8. Ozkaraoglu, E.; Suzer, S. "Gold Nanoparticles in PMMA Matrix: in-situ Synthesis and Gold Nanoparticle-PMMA interactions", Oral Presentation, 13th European Conference on Applications of Surface and Interface Analysis, October 18-23 2009, Antalya, TURKEY

  9. Ozkaraoglu, E.; Suzer, S. "Gold Nanoparticles in PMMA Matrix: in-situ Synthesis and Gold Nanoparticle-PMMA interactions", Oral Presentation, 8th International Conference on Advanced Polymers via Macromolecular Engineering, October 4-7 2009, Dresden, GERMANY

  10. Ozkaraoglu, E.; Suzer, S. "Gold Nanoparticles in PMMA Matrix: in-situ Synthesis and Gold Nanoparticle-PMMA interactions", Oral Presentation, 26th European Conference on Surface Science, August 30 - September 4 2009, Parma, ITALY

  11. Ozkaraoglu, E.; Suzer, S. "UV Induced in-situ Synthesis of Gold Nanoparticles within PMMA Films", Oral Presentation, 5th Nanoscience and Nanotechnology Conference, June 9-11 2009, Eskisehir, TURKEY

  12. Ozkaraoglu, E.; Tunc, I.; Suzer, S. "UV and X-Ray Induced Production of Au and Pt Mono/Bimetallic Nanoparticles within Polymer Films", Poster Presentation, 12th European Conference on Applications of Surface and Interface Analysis, September 9-14 2007, Brussels, BELGIUM

  13. Ozkaraoglu, E.; Tunc, I.; Suzer, S. Synthesis and Characterization of Gold Nanoparticles with UV radiation and/or X-rays within Polymer Films", Oral Presentation, 10th National Spectroscopy Conference, July 4-7 2007, Izmir, TURKEY
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Projects

1001

TUBITAK, 1001 Project

Principal Investigator: Eda YILMAZ

Project Budget: 371.400 TRY

Status: Ongoing

Cost

TUBITAK, COST Project

Principal Investigator: Eda YILMAZ

Project Budget: 302.130 TRY

Status: Ongoing

1001

TUBITAK, 1001 Project

Principal Investigator: Eda YILMAZ

Project Budget: 268.560 TRY

Status: Completed

2232

TUBITAK, 2232 Project

Principal Investigator: Eda YILMAZ

Project Budget: 103.000 TRY

Status: Completed

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Teaching

MSN533

MSN 533 - Nanomaterials for Energy Conversion and Storage

Producing and storing energy efficiently has always been one of mankind’s biggest challenges. Research efforts in these topics have gained an unseen momentum since it became clear that environmental problems will continue to grow if the energy we use is not obtained from sustainable resources. Electrochemical energy conversion and storage applications are founded in response to these efforts and have been studied for decades. Some important electrochemical devices like fuel cells, solar cells, supercapacitors and batteries, are energy conversion and storage systems that will be discussed in the content of this course. This course is designed to give students, from different disciplines, a general understanding of electrochemical concepts and methods, relate this knowledge to currently used or studied energy conversion and storage systems and discuss the importance of nanomaterials for the improvement of these systems.

Contact Information

Contact

Address

Bilkent Universitesi
Ulusal Nanoteknoloji Araştırma Merkezi (UNAM)
06800 Ankara TURKEY
Office No: 307

Phone

+90 (312) 290 8028

E-mail

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