Titel der Dissertation:
Development of porous surface functionalized carbon materials for electrochemical and catalytic applications (Arbeitstitel)
Over the last decade porous surface functionalized carbon materials have gained much attention as a metal-free alternative for catalysts and electrode materials. With cheap, non-toxic educts and easy ways of fabrication they have become of high interest in current research. Their catalytic and electrochemical properties are mainly influenced by the pore-size distribution, the chemical composition and the proportion of graphitic structures. Therefore a modular concept of synthesis is highly desirable in order to design customized carbon materials with specific properties.
In this current work a library of systematically modified porous carbons in regard of the impurity atom sulphur is in development. Different sulphur-containing precursors are being tested in a hard template assisted synthesis route. This work shall later be expanded for example to phosphorus or the codoping with sulphur and nitrogen. The influence of the electronic properties on electrochemical and catalytic applications (batteries, capacitators) induced by doping the carbon material with heteroatoms will be tested in cooperation with other working groups.
Bachelor Thesis, Reaktionen von drei- und vierwertigen Metallen mit Schwefel- und Selensäurederivaten, Carl-von-Ossietzky Universität Oldenburg, 2014.
Master Thesis, Entwicklung einer neuen Methode zur Charakterisierung acider Zentren von Zeolithen mittels Flammenionisationsdetektor, Carl-von-Ossietzky Universität Oldenburg, 2016.
Peters, S.; Bölte, J.-H.; Thomé, A. G.; Rößner, F., Reductive Decomposition of Supported Metal Nitrates used as Catalyst Precursors,50. Jahrestreffen deutscher Katalytiker, Weimar 2017.
Titel der Dissertation:
Chemical reactivity on disturbed silicon surfaces (Arbeitstitel)
During the manufacturing, cutting and polishing process of silicon the surface becomes deformed. These deformations result in lattice defects and mechanical stress conditions, modifications due to phase transitions and local contaminations, which reach into the solid for several micrometers and greatly influence the chemical reaction behaviour of the material. Such disturbed surfaces exhibit unusual reaction behaviours which manifests itself in higher reaction rates or unexpected reaction processes. We create deformed silicon surfaces using scratching, indentation and cutting processes to analyse their topological behaviour before and after a reaction using confocal and electron microscopy. Furthermore, we identify the relative lattice deformations and modifications of the silicon material using Raman microscopy to compare the reactivity of disturbed and undisturbed surfaces. We also analyse the changed kinetics and mechanisms of typical reactions on silicon surfaces like etching, oxidation, surface modification and gas phase reactions.
I started my studies in chemistry at the BTU Cottbus-Senftenberg 2011. During my bachelor studies, I had two internships in 2014. The first focused on “Raman-microscopic research of stress fields on Si” in the group of prof. J. Acker where the dependency between Raman-Shifts and the chemical reactivity was discovered first. Afterwards an Internship at Wacker chemistry was done with the focus on the “online analytics of trace elements in silane-mixtures”. During this time, I learned several techniques to analyse silanes on production lines and learned about the process of silicon production. 2015 I finished my bachelor thesis at the institute for solid state and material research Dresden about the “wet-chemical etching of sputtered W- and Mo- thin layers of SAW-applications” advised by Dr. S. Menzel and prof. J. Acker. Using electron microscopy and sputtering processes to create metallic thin layers and optimizing their shape using wet-etching I received the award for the best bachelor-thesis 2015 at the BTU. Furthermore, the data was published in Thin Solid Films Vol. 612 (2016). 2016 I also started my master studies at the BTU Cottbus-Senftenberg focusing on inorganic materials. My master-thesis I finished 2016 at Wacker chemistry in the topic of “characterization of fused silica systems for the use of 3D-printing” advised by Dr. G. Gaudig and prof. J. Acker. With the focus on rheological studies and 3D-printing behaviour I identified several mixtures possible for medical 3D-printing that are still in the process of being patented. My doctoral-thesis I started January 2017 continuing my earlier work in this field focusing on the chemical reactivity on disturbed silicon surfaces.
Titel der Dissertation:
Molecular Beam Epitaxy growth of Si, Ge and SixGe1-x nanowires and modeling of synthesis conditions for multi-component compounds for thermoelectrics (Arbeitstitel)
Nanowires (NWs) are one-dimensional crystalline objects with specific physical properties due to their reduced dimensionality. The integration of Si and particularly Ge NWs in sophisticated Si electronics would be desirable, but the realization will remain on the level of research and development for years to successfully implement in the industry, as the growth and handling of NWs is a challenging task.
We focus on the controlled growth of Si, Ge, and SiGe NWs on Si(111) substrates by Molecular Beam Epitaxy (MBE). Hereby, solid sources of the elements, Au, Si and Ge were used. Au serves as catalyst, where the NW growth is located and take place via the Vapor-Liquid-Solid (VLS) mechanism. Our work is targeted on arrays of doped SiGe NWs for thermoelectric devices applicable to high temperatures. NWs could be helpful to improve the figure of merit of such devices by reducing the thermal conductivity due to phonon scattering on the sidewalls and at composition changes inside the NWs.
2010 – 2016: Study in chemistry (B.Sc.) and applied chemistry (M.Sc.) at the Brandenburg University of Technology Cottbus – Senftenberg
Work & Profesional Experince
- Internship at Max Planck Institute for Chemical Physics of Solids in Dresden, topic: „Synthese und Charakterisierung neuer intermetallischer Verbindungen“
- Bachelor-Thesis at Leibniz Institute for Catalysis in Rostock, topic: „Heterogen katalysierte CO2-Hydrierung zu Methan an Ruthenium und Nickel-haltigen Katalysatoren unter erhöhten Drücken.“
- Foreign Internship at TUM-CREATE in Singapore, topic: „Development of Sodium Ion Battery Systems“
- Master-Thesis at Fraunhofer Institute for Material and Beam Technology IWS in Dresden, topic: „Membranen und Schutzschichten für den Lithium-Schwefel-Akkumulator“
Titel der Dissertation:
Thin and conformal ALD deposited Co and Ni metal layers for battery and catalytic applications (Arbeitstitel)
The goal of the thesis will be the investigation and development of atomic layer deposition (ALD) of thin Cobalt (Co) and Nickel (Ni) layers. Here two directions should be followed. On the one hand, on the basis of thermal ALD, the development should be established by the deposition of pure (NiO, CoO) and ternary oxide layers (CoNiO) and their subsequent reduction. In contrast, plasma enhanced ALD (PEALD) will be used to follow a direct route of metal deposition, where plasma radicals (oxygen, hydrogen, nitrogen) will be used to fulfil reductive conditions where thermal activation is not sufficient. Metal-organic precursors will be used with special focus on their complex properties and technical manageability.
The deposited layers will be characterized by spectroscopic and microscopic methods to determine the layer composition, morphology, and homogeneity. Further essential criteria will be the conductivity of the layers. The advantages and disadvantages between thermal ALD and PEALD have to be worked out and weighted for potential applications. Thin and conformal Co and Ni metal layers are of interest for the CMOS technology (silicide formation for small contact resistances, adhesion layer for interconnects), for magnetic and nano-crystalline non-volatile memories and in particular for catalytic applications. In addition, ternary Co/Ni oxides are used in lithium-ion batteries; here the Co/Ni ratio might be controlled very effectively by ALD. In many applications, the conformal growth on 3D structures is important for the efficiency and life-time of the devices. The conformity of the layers depends strongly on the deposition method; here the ALD is favourable due to the extremely precise thickness control in comparison to other techniques (CVD, PVD).
To sum up, the topic has a direct link to energy conversion moreover ALD layers can contribute to performance improvements and therefore to higher energy efficiency.
I was born in Bombay, India and raised in Shiraz, Iran. I completed my BSc studies in physics at IAU, Shiraz Branch in 2011. During my bachelor, acquired substantial knowledge corresponding to the various branches of physics so that created a motivation to pursue my master degree which completed in the field of Solid State Physics at IAU, Tehran Science and Research Branch (Fars) in 2015. The main focus in my MSc dissertation has been the effect of nanoparticles inclusions on properties of high-temperature superconductors with regard to the most important application of these materials such as microelectronics components, superconducting wires, cables, and magnets. I have carried out some research projects parallel to my education and also after graduation, in the Microelectromechanical systems (MEMS) area at K.S.P.R. Technical-Engineering Company, Tehran, Iran. I started my PhD programme at Faculty 1, Chair of Applied Physics / Sensor Technology, BTU, Cottbus in early July 2018. Based on extensive researches that have been carried out at BTU, I am enthusiastic to become even more attracted to new research horizons, to gain more valuable research experiences and developing my knowledge.
Titel der Dissertation:
Studies and optimization of thin film layer properties in high efficient electrostatic actuators (Arbeitstitel)
Brandenburg University of Technology Cottbus−Senftenberg and Fraunhofer Institute for Photonic Microsystems demonstrated a novel, high efficient electrostatic actuator principle to be integrated into various MEMS (Micro-Electro-Mechanical Systems) sensors and actuator systems.
The doctoral thesis will focus on integration of the novel principle into a CMOS-compatible process. Hereby, investigation of material properties taking into account high electrical and mechanical loads is of particular interest. The influence of various dielectric and metal layer materials, interfaces and their quality including stoichiometric aspects on parasitic dielectric charging as well as on electrical and mechanical degradation in operation has to be studied in detail. In close consultation with process engineers of Fraunhofer IPMS’ cleanroom facilities, suitable combinations of layer materials and deposition and patterning process conditions have to be selected and characterized by means of test devices, applying C-V and I-V measurement methods, as well by means of various micro- and nanoscopic material characterization methods. Based on the findings of these and further characterization results complete functional actuator layers will be devised, fabricated and characterized. A further objective is to correlate the observed effects of the actuators with the characterization results of single layers and layer stacks and to develop a semi-quantitative physical model to describe respectively predict failure phenomena. Thereby, the final goal is to develop approaches towards highly reliable device operation.
I completed my bachelor’s degree in Electrical and Electronics Engineering from Visveswaraya Technological University, India with distinction. After my bachelor studies, I worked as assistant manager in control room of aluminium smelter plant of Vedanta Aluminium Ltd., Jharsuguda (India) for three years. The industrial work experience gave me an important insight in the functioning of professional multinational companies. I decided to further my academic knowledge and came for my master studies to Germany. I finished my masters in Electrical Communication Engineering from University of Kassel, Germany with “sehr gut” (highest grade class). My master’s studies were focused on the areas of microsystems, optoelectronic devices and microwave circuits. I gained knowledge in microsystems designing, fabrication and characterization, and my master’s project and thesis were concentrated on this discipline. I worked in clean room and measurement labs of Institute of Nanostructure Technologies and Analytics (INA), University of Kassel for almost one and a half years, first as a master thesis student and then as a research assistant. Currently, I am a doctoral candidate at Brandenburg University of Technology Cottbus-Senftenberg (Graduate Research School Cluster “FuSion”) and Fraunhofer Institute for Photonic Microsystems (Mesoscopic Actuators and Systems Research Group), Cottbus-Dresden. My doctoral thesis topic is titled “Studies and optimization of thin film layer properties in high efficient electrostatic actuators” and concentrates on development of highly efficient electrostatic actuators. I have always been an enthusiastic for application-oriented research and development of energy-efficient microsystems that can benefit society in general. Thus, this research topic is an ideal field for me to carry out my research work. I believe this opportunity will give me a good foundation for realizing my long-term goal of becoming an academic researcher.
Dr. Marvin Zöllner
Titel der Dissertation:
“Virtual GaN by patterned Si wafer” (Arbeitstitel)
The aim of the project is the integration of GaN on Si for future applications in optoelectronics.
I hold a BSc in Chemistry and a MSc in Advanced Materials-Specialist in Nanotechnology from Universidad Autónoma de Madrid. During my studies, I was awarded with a scholarship to work as a research assistant, from 2014 to 2016, in the Faculty of Science of Universidad Autónoma de Madrid. My research was focused on the improvement of ZnO biocompatibility. Meanwhile my studies, I wrote my first paper and I have also participated in several Young Researchers Meetings organized by “Instituto Universitario de Ciencia de Materiales Nicolás Cabrera” in Madrid as well as in my first International Workshop. Currently, I am a PhD candidate at IHP- Leibniz-Institut für innovative Mikroelektronik.
Titel der Dissertation:
Characterization and growth of GeSn nanostructures for optoelectronics (Arbeitstitel)
GeSn alloys are an interesting new class of semiconductors owing to their bandgap, tunable by varying the Sn content, and their compatibility with modern Si technology. GeSn growth techniques in the moderate and high Sn content regime has prompted the development of GeSn based photodetectors with increased photoresponsivity across the telecommunication band (>1.55 µm) and an optically pumped direct bandgap GeSn laser for Sn contents of 2 and 13 %, respectively. The direct growth of GeSn on Si(001) bears great challenges, due to a large lattice mismatch, low Sn solubility in Ge (< 1 %) and enhanced Sn segregation. Past efforts mainly focused on planar GeSn systems which are typically based on low temperature chemical vapor deposition (CVD) and molecular beam epitaxy (MBE) techniques. Research on methods to synthesize nanostructured GeSn remains, however, limited to date, despite its potential to improve the material quality and the possible use of GeSn in nanoscale electronics, for example as stressors in strained Ge Fin field effect transistors (FETs).
I studied chemistry in my bachelor and master course (2009 to 2015) at the Leipzig university of Leipzig. Since my bachelor thesis I have been focusing my research on physical chemistry. The main topic in my bachelor/master studies was the characterization of metal(oxide) surfaces using techniques such as x-ray photoelectron spectroscopy. Furthermore, I have also carried out experiments at the synchrotron facility of BESSY II in Berlin.
In 2015, I started my PhD at IHP (innovations for high performance microelectronics) in Frankfurt (Oder) and I am also a PhD student at the BTU Cottbus. Ever since, my research has extended to several other characterization methods such as x-ray/electron diffraction and photoluminescence as well as to the growth of semiconductor nanostructures itself.
Currently, I am in the second year of my PhD studies and I have participated in numerous national conferences as well as international ones. In April I have taken the great opportunity to stay as an overseas researcher at Nagoya university in Japan for 3 months.
Titel der Dissertation:
Template assisted synthesis of porous carbons with systematically varied properties for the catalysis of redox reactions with oxygen (Arbeitstitel)
Over the last decade porous surface functionalized carbon materials have gained much attention as a (noble)metal-free alternative for catalysts and electrode materials. With cheap, non-toxic educts and easy ways of fabrication they have become of high interest in current research. Their catalytic and electrochemical properties are mainly influenced by their textural properties (specific surface area, pore-size distribution), the chemical composition (modification with foreign atoms) and their structural features (for example graphitic structures). Therefore a modular concept of synthesis is highly desirable in order to design customized carbon materials with specific properties.
In this current work a library of systematically modified porous carbon catalysts in regard of the variation of the textural properties, the introduction of the foreign atoms nitrogen and/or iron and the creation of additional graphitic structures are in development. Different nitrogen-containing precursors are being tested in a hard template assisted synthesis route by using (iron modified) silica gel or porous concrete as templates. The so obtained catalysts (more than 100 different porous carbons were already synthesized) were characterised in regard to their before mentioned properties and tested as catalysts for redox reactions with oxygen, namely in the oxygen reduction reaction (ORR), the oxidative dehydrogenation of ethyl benzene (ODH) and the oxidation of sulphurous acid to sulphuric acid (OSA), which were done amongst others in cooperation with other working groups.
Bachelor Thesis, Synthese von chiralen Steroidbausteinen, Universität Leipzig, 2009.
Master Thesis, Thermobehandlung von Alkaliborosilikaten und TiO2-haltigen Gläsern unter Einfluss von Mikrowellen sowie Untersuchungen zu Extraktionsbedingungen, Universität Leipzig, 2012.
Utgenannt, S.; Hansen, F.; Klepel, O.; Jarczewski, S.; Wach, A.; Kuśtrowski, P., Carbon based catalysts prepared by template assisted route,Catalysis Today 249 (2015) 38–44.
Klepel,O.; Erlitz,M.; Garsuch, A.; Scholz (nee Böhme), K.; Suckow, M.; Taubert, M; Utgenannt, S., Template assisted synthesis of porous carbons revisited – where does the porosity come from?, Microporous and Mesoporous Materials 224 (2016) 163-167.
Reichardt,C.; Utgenannt,S.; Stahmann,K.-P.; Klepel,O.; Barig,S., Highly stable adsorptive and covalent immobilization of Thermomyces lanuginosus lipase on tailor-made porous carbon material, Biochemical Engineering Journal 138 (2018) 63-73.
Investigations of carbon based catalysts, 3. Naturwissenschaftstag Lausitz , BTU Cottbus - Senftenberg, 2015.
Development of carbon based catalysts, 5. Naturwissenschaftstag Lausitz , BTU Cottbus - Senftenberg, 2017.
Poster,Real role of surface composition and textural properties of mesoporous carbons in control of their catalytic activity in oxidative dehydrogenation of ethylbenzene, CarboCat VI, Trondheim, 2014.
Poster,Carbon based catalysts with systematically varied properties, 27. Deutsche Zeolithtagung, Oldenburg, 2015.
Poster,Oxidation of aqueous sulfurous acid on porous carbons as a catalytic test reaction, 27. Deutsche Zeolithtagung, Oldenburg, 2015.
Poster,Carbon based catalysts with systematically varied properties prepared by template assisted routes, 48. Jahrestreffen Deutscher Katalytiker, Weimar, 2015.
Poster,A modular concept for the preparation of carbon based catalysts, Carbon, Dresden, 2015.
Poster,Template assisted synthesis of porous carbons with systematically varied properties for the catalysis of redox reactions with oxygen, 29. Deutsche Zeolithtagung, Frankfurt, 2017.
Poster,Modular synthesis of carbon based catalysts with systematically varied properties, 50. Jahrestreffen Deutscher Katalytiker, Weimar, 2017.
Poster,Template assisted synthesis of porous carbon catalysts with systematically varied properties, 7th FEZA Conference, Sofia, 2017.
Poster,Oxidation of aqueous sulfurous acid to sulfuric acid on porous carbons as a catalytic test reaction: potential and limitations, 30. Deutsche Zeolithtagung, Kiel, 2018.
Poster,Oxidation of aqueous sulfurous acid to sulfuric acid on porous carbons as a catalytic test reaction: potential and limitations, Weimar, 2018.