Nanomaterial Chemistry (in English)
Annotation of PhD topics in Nanomaterial Chemistry (Guarantor: doc. RNDr. Robert Prucek, Ph.D.)
Possibility to actively control charge states on atomic scale in nanostructures opens new horizons in the field of nanoelectronics. To get more insight into processes of charge transfer on atomic scale requires new theoretical approaches. The aim of this work is to employ the density functional theory and its application on selected cases charge transport in nanostructures. Theoretical simulations will be performed in close collaboration with ongoing experimental measurements. Development of computational methods is expected.
Chemical and physical properties of molecular nanostructures on surfaces investigated by means of scanning probe microscopy - doc. Ing. Pavel Jelínek, Ph.D.
The current development of the scanning microscopes working in ultrahigh vacuum allows high-resolution measurements of atomic force and tunneling currents on individual atoms or molecules deposited on the surface of solids. Simultaneous measurement of the atomic force and tunneling current opens up completely new possibilities for the characterization of single molecules or molecular nanostructures on solid surfaces. The candidate will learn to work with atomic force microscope and scanning tunneling microscope in ultra-high vacuum. The aim of this work is carried out high-resolution measurements of the atomic and electronic structure of selected molecules deposited on solid surfaces. The main objective is to study chemical and physical properties of the molecular nanostructure by means of scanning probe microscopy.
Catalytic activity of metal nanoparticles and their composites for applications in energy production - doc. RNDr. Libor Kvítek, CSc.
Metal based nanomaterials are frequently studied due to the number of their unique properties. Mainly their catalytic activity is important in the chemical industry, which is primarily associated with a high ratio of atoms or molecules on the surface of the particle to its volume. Current developments in the field of nanotechnologies for energy applications are related directly to this high catalytic activity of nanomaterials. In addition to research aimed at development of new power generation systems, either chemically (electrochemical cells) or solar energy conversion, many research teams are also focused on energy conservation in energy-rich compounds. One such reaction that allows the energy to be stored for later use while eliminating some of the unfavorable carbon dioxide emissions is the reduction of this fossil fuel combustion product to produce many organic compounds for reuse in the energy industry or in the chemical industry. Carbon dioxide can be reduced by hydrogen to form a series of hydrocarbons and other organic compounds, typically methanol. This reaction uses similar catalysts as well-known Fischer-Tropsch synthesis which proceeds efficiently with the aid of metal-based catalytic systems. Long-term experience in the research of catalytic activity of metal nanomaterials at laboratories of Department of Physical Chemistry UPOL and RCPTM has recently led to the development of an efficient composite nanocatalyst for this reaction based on copper nanoparticles bound to nanostructured iron oxide. The first tests of this catalyst, in collaboration with the catalytic group of Dr. Vajda at Argonne National Laboratory (Chicago, USA), showed high activity of this catalyst for hydrocarbon production. Further research will be carried out using a PID micro-reactor for study of heterogeneous catalysis in a gaseous reaction system linked to a GC/MS analytical instrument. The main aim of this PhD thema is focus on the research and development of the catalytic system based on nanoparticles of noble metals combined with iron oxide nanoparticles with high catalytic activity for low-temperature (up to 300 ° C) hydrogenation of carbon dioxide to produce energy-rich compounds usable in energetics and chemical industry.
Graphene is without any doubt an extraordinary material. Some of its properties (hydrophobicity, zero band-gap, low chemical reactivity), however, limit its application potential, e.g., in electronics and biosensing. We seek for new preparation routes for tailored graphene modifications. The modification can be achieved via covalent as well as noncovalent approaches (Chem. Rev., 112(11), 6156-6214, 2012). The framework topic focuses on development of alternative routes for synthesis of graphene derivatives, on understanding the mechanism of chemistries of carbon 2D materials and understanding of physical-chemical properties of graphene derivatives. The aims will be fulfilled via experimental (synthesis, characterization via e.g., HRTEM, SEM, AFM, XPS, and sensing, and (electro)catalytic applications) or computational (DFT, advanced DFT and post-HF) methods and simulation (all-atom and coarse-grained molecular dynamics simulations) techniques. The particular topics will be focused on design, synthesis, and characterization of new graphene derivatives with tailored properties (e.g., magnetic, electronic, dispersibility etc.), understanding the strength and nature of noncovalent interactions to graphene and graphene derivatives, application of graphene derivatives in sensing, catalysis and energy storage.
Nanostructured materials are unique due to specific physicochemical properties, which are also reflected in the specific interaction with living organisms, thanks to which nanomaterials exhibit unique biological properties. The useful properties of nanomaterials with biological properties are wide and can be used, for example, in medicine to treat or diagnose diseases, biologically active nanomaterials can be used in industries or environmental applications to remove unwanted biological, especially microbial, contamination. A typical example is silver nanoparticles, which have high antimicrobial activity, which can be used in the treatment of microbial infections, including those caused by highly resistant bacterial strains in which treatment with conventional antibiotics fails. On the other hand, it is necessary to take into account the possible adverse biological effects of nanomaterials in the interaction with biological systems, which may occur precisely due to their unique and unusual biological properties. The study of the mechanism of interaction of nanomaterials with biological systems at various cellular levels and their use for biological and medical applications thus represents a very interesting and diverse field of scientific research.
Due to their specific physicochemical properties, noble metal nanoparticles show high chemical activity, in particular high catalytic activity. The catalytic effects are due to the chemical nature of the metals themselves, and in addition the nanoscale and morphology of the particles of these metals can be increased, leading to a huge increase in the surface area of the metal necessary for efficient heterogeneous catalysis. Nanoparticles of group I B metals show high catalytic activity especially in redox reactions, platinum group metals and related metals are then highly effective in reactions involving hydrogen, especially with regard to the synthesis of simple hydrocarbons and their derivatives (eg Fischer-Tropsch synthesis). In the field of catalytic applications, research and development can focus mainly on the synthesis and development of highly catalytically effective nanomaterials based on metals and their compounds applicable e.g. to environmental technologies (e.g. redox reactions and liquidation of pollutants), or in industrial chemistry in many chemicals. processes (ethylene oxide production, Fischer-Tropsch synthesis) or in the field of energy technologies (CO2 reformation to methanol, highly active electrodes for fuel cells). However, practical applications of nanomaterials are often accompanied by aggregate instability of metal nanoparticles or limited possibility of separation after the reaction in real application systems. One way to prevent these side effects is to anchor the metal nanoparticles to selected inert substrates. Examples are natural aluminosilicate materials, metal oxides or magnetic materials such as iron oxides, which further facilitate the magnetic separation of the catalyst after the reaction.
Preparation of nanoparticles and nanocomposites for catalytic applications - doc. RNDr. Robert Prucek, Ph.D.
Current developments in the field of nanotechnologies are moving from the preparation and use of isolated nanoparticles to systems where they are firmly captured on a suitable substrate (colloidal particles, microparticles or macrosystems). Such composites exhibit unique physicochemical properties, different from the nanoparticles themselves. In addition to the increased aggregate stability of nanoparticles, there is often a synergistic effect of improving the physicochemical properties of the mentioned materials (e.g. catalytic activity, optical properties, separation, aggregate stability, etc.).
The aim of this work will be research and development in the field of preparation, characterization and application of nanoparticles of precious metals (copper, silver, gold, platinum, palladium, etc.) or their compounds. The research area will focus on the development and optimization of methods for the preparation of nanoparticles and nanocomposites based on these metals and their compounds (in the form of aqueous dispersions, self-organized layers or immobilized particles on carriers such as: SiO2, Al2O3, ZrO2, FexOy, glass, quartz, etc. .) including their characterization (size, morphology, stability, etc.). The mentioned materials will then be studied and tested in terms of their effectiveness for the purposes of heterogeneous catalysis or spectroscopic applications (surface-enhanced Raman spectroscopy).
In the field of catalysis, micro or nanoparticles or nanocomposites are used on a very large scale in the field of organic synthesis (Ullmann synthesis, Fischer-Tropsch synthesis, ammonia preparation (Haber-Bosch reaction), hydrogenation or dehydrogenation reaction, Suzuki reaction, etc.), further in the field of very intensively developing areas such as fuel cells, photovoltaics, photocatalysis, photochemical water splitting, catalysts in automobiles for the oxidation of unburned hydrocarbons, carbon monoxide and the reduction of nitrogen oxides. Another important application of these materials is their use in advanced oxidation processes used for remediation technologies used for wastewater treatment and old environmental burdens. A common and common requirement for industrial application is their ability to degrade toxic and often persistent organic pollutants, which resist or directly deactivate the traditionally used biological stage, which forms an integral part of most wastewater treatment plants.
Preparation of nanoparticles and nanocomposites for spectroscopic applications - doc. RNDr. Robert Prucek, Ph.D.
Surface-enhanced Raman spectroscopy is one of the modern analytical techniques for detecting very low concentrations of substances. As a result of the constant development of Raman spectrometers, these instruments are becoming more affordable, and as a result, the number of these instruments is expanding not only in scientific workplaces, but especially in these laboratories to become a common part of commercial laboratories. A very important area where these devices can be found, whether in the form of classic or especially mobile versions, are selected units of the police, fire brigade or army, where these instruments are used to identify flammables, drugs, explosives, etc. Raman spectroscopy has a very significant potential, which predestines it for future expansion into many areas of human activity (rapid and sensitive detection of explosives, drugs, or detection of markers for disease determination, toxicology, forensic analysis, etc.), so the goal will be reproducible preparation of effective reliable, easy-to-use substrates based on silver and gold.
RNDr. VAJDA Štefan CSc., Dr. habil. - Head of Department of Nanocatalysis, J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Prague
The recently established Department of Nanocatalysis of the J. Heyrovsky Institute of Physical Chemistry of the Czech Academy of Sciences, in collaboration with department of Physical chemistry, Palacký University in Olomouc, has several openings for PhD theses. Topics include, but are not limited to:
- Oxidative and non-oxidative dehydrogenation of alkanes,
- CO oxidation,
- CO2 conversion.
The catalysts are made of (i) subnanometer clusters of atomically precise size and composition supported on oxide and carbon based supports, deposited from molecular beams in vacuum and (ii) nanoparticulate catalyst prepared by more conventional wet chemical routes. Catalysts are tested for their performance on experimental reactor system with detection of the products by the mass spectrometer and gas-chromatography. Prepared catalysts are characterized by advance electron microscopy and other techniques for solid phase characterization. For more information about the research activities please visit
www.heyrovsky-chair.eu
