A5036544948- Catalytic Processes in Materials Science
- Catalysis and Oxidation Reactions
- Copper-based nanomaterials and applications
- AI-based Problem Solving and Planning
- Electronic and Structural Properties of Oxides
- Electrocatalysts for Energy Conversion
- Logic, Reasoning, and Knowledge
- TiO2 Photocatalysis and Solar Cells
- Advanced Photocatalysis Techniques
- 2D Materials and Applications
- Semantic Web and Ontologies
- ZnO doping and properties
- MXene and MAX Phase Materials
- Chalcogenide Semiconductor Thin Films
- Semiconductor materials and devices
- Constraint Satisfaction and Optimization
- Gas Sensing Nanomaterials and Sensors
- Advanced Chemical Physics Studies
- nanoparticles nucleation surface interactions
- Quantum Dots Synthesis And Properties
- Education, Psychology, and Social Research
- Nanomaterials for catalytic reactions
- Force Microscopy Techniques and Applications
- Transition Metal Oxide Nanomaterials
- Surface and Thin Film Phenomena
Charles University
2011-2022
University of Pardubice
2017-2021
Laboratoire d'Analyse et d'Architecture des Systèmes
2015
Centre National de la Recherche Scientifique
2015
Abstract Single-atom catalysts maximize the utilization of supported precious metals by exposing every single metal atom to reactants. To avoid sintering and deactivation at realistic reaction conditions, atoms are stabilized specific adsorption sites on catalyst substrates. Here we show combining photoelectron spectroscopy, scanning tunnelling microscopy density functional theory calculations that Pt ceria most ubiquitous defects solid surfaces—monoatomic step edges. segregation steps leads...
Thin films of reduced ceria supported on metals are often applied as substrates in model studies the chemical reactivity based catalysts. Of special interest properties oxygen vacancies ceria. However, thin prepared by established methods become increasingly disordered concentration increases. Here, we propose an alternative method for preparing ordered physical vapor deposition and interfacial reaction Ce with CeO2 films. The yields bulk-truncated layers cubic c-Ce2O3. Compared to these...
Surface composition of the highly selective Ni–Cu catalysts was characterized by NAP-XPS under conditions relevant to HDO reaction.
Atomic layer deposition (ALD) represents a unique technique that allows to coat uniformly various high aspect ratio (HAR) porous nanostructures, in addition its traditional role flat substrates (e.g. Si wafers). Self-organized anodic TiO2 nanotube (TNT) layers belong among the most investigated inorganic nanostructures. They possess highly functional materials with promising application potential across many technological fields. Herein, we review utilization of ALD for functionalization TNT...
This paper presents an effective hydrothermal route to decorate various types of anodic 1D TiO2 nanotubes (TiO2 NTs) with magnetite nanoparticles (Fe3O4 NPs), yielding a magnetically guidable and active photocatalyst. A unique portfolio NTs including single-tube, single-walled, double-walled ones was used. Optimal conditions for uniform decoration these by Fe3O4 NPs (two different loadings) using wet chemical synthesis based on oleate approach were found. The resulting TiO2NTs@Fe3O4NPs shown...
Active catalytic sites have traditionally been analyzed based on static representations of surface structures and characterization materials before or after reactions. We show here by a combination in situ microscopy spectroscopy techniques that, the presence reactants, an oxide catalyst's chemical state morphology are dynamically modified. The reduction Cu2O films is studied under ambient pressures (AP) CO. use complementary allows us to identify intermediate phases determine how reaction...
Adjustable morphology and degree of reduction represent desirable properties model oxide substrates for heterogeneous catalysis. We investigate these in CeO2 (ceria) thin films on Cu(111) using scanning tunneling microscopy photoelectron spectroscopy. identify growth mechanisms ceria Cu(111): formation incomplete interfacial layer three-dimensional pyramids by stacking monolayer-high islands. Using mechanisms, we control the coverage, number open monolayers, step density Cu(111). Annealing...
Changes of stoichiometry in reducible oxides are inevitably accompanied by changes the oxide structure. We study relationship between and structure thin epitaxial films reduced ceria, CeOx, 1.5 ≤ x 2, prepared via an interface reaction a ceria film on Cu(111) Ce metal deposit. show that transition limiting stoichiometries CeO2 Ce2O3 is realized equilibration mobile oxygen vacancies near surface film, while fluorite lattice cerium atoms remains unchanged during process. identify two...
Recent advances in additive manufacturing (AM) and 3D printing technologies have led to significant growth the use of industry, which allows for physical realization previously difficult manufacture designs. However, certain cases AM can also involve higher production costs unique in-process complications, motivating need solve new optimization challenges. Optimization is relevant involves multiple fields including mechanical engineering, materials science, operations research,...
Reactions of reduced cerium oxide CeOx with water are fundamental processes omnipresent in ceria-based catalysis. Using thin epitaxial films ordered CeOx, we investigate the influence oxygen vacancy concentration and coordination on oxidation by water. Upon changing stoichiometry from CeO2 to Ce2O3, observe a transition slow surface reaction productive H2-evolving yields exceeding capacity indicating participation bulk OH species. Both experiments ab initio calculations associate effective...
Single-atom catalysts represent an essential and ever-growing family of heterogeneous catalysts. Recent studies indicate that besides the valuable catalytic properties provided by single-atom active sites, presence sites on catalyst substrates may significantly influence population supported metal nanoparticles coexisting with single atoms. Treatment ceria-based in oxidizing or reducing atmospheres was proven to provide a precise experimental control size Pt and, correspondingly, activity...
Here, we demonstrate the preparation of 2D MoSe 2 structures by atomic layer deposition technique. In this work, use ((CH 3 ) Si) Se as precursor and Mo(CO) 6 or MoCl 5 Mo precursors. The X‐ray photoelectron spectroscopy (XPS) analyses prepared samples have revealed that using obtained structure is nearly identical to reference powder sample while composition from contains a significant amount oxygen atoms. Further inspection as‐deposited via scanning electron microscopy (SEM), diffraction...
A novel 1D conical nanotubular CdS/TiO<sub>2</sub>heterostructure possesses synergic effects that yield a superior photon-to-electron conversion and shows promising perspectives in photovoltaics.
Discontinuous ceria layers on Cu(111) represent heterogeneous catalysts with notable activities in water–gas shift and CO oxidation reactions. Ultrathin islands these are composed of monolayers exhibiting CeO2(111) surface ordering bulklike vertical stacking (O–Ce–O) down to a single monolayer representing the oxide-metal interface. Scanning tunneling microscopy (STM) reveals marked differences strain buildup structure oxygen vacancies this first compared thicker Cu(111). Ab-initio...
The adsorption of CO on Pt nanoclusters grown in a regular array template provided by the graphene/Ir(111) Moiré was investigated means infrared-visible sum frequency generation vibronic spectroscopy, scanning tunneling microscopy, X-ray photoelectron spectroscopy from ultrahigh vacuum to near-ambient pressure, and ab initio simulations. Both terminally bridge bonded species populate nonequivalent sites clusters, spanning first second-layer terraces borders edges, depending particle size...
Two-dimensional MoS2 nanostructures are highly interesting and effective in a number of energy-related applications. In this work, the synthesis ultra-thin nanosheets produced by thermal Atomic Layer Deposition (ALD) process is reported for first time using previously unpublished set precursors, namely bis(t-butylimido)bis(dimethylamino)molybdenum hydrogen sulfide. These homogenously deposited within one-dimensional anodic TiO2 nanotube layers that act as high surface area conductive support...
Adsorption and reaction of formic acid on stoichiometric CeO2(111), partially reduced CeO2–x, Pt/CeO2(111) films prepared Cu(111) were studied by means synchrotron radiation photoelectron spectroscopy (SRPES), resonant photoemission (RPES), infrared reflection absorption (IRAS), temperature-programmed desorption (TPD). On all samples, the principal species formed during adsorption below 160 K formate molecular acid. In presence Pt particles, predominantly localized at 100 K, ceria or above...
This paper reports on FAPE (Flexible Acting and Planning Environment), a framework integrating acting planning the basis of ANML modeling language. is recent proposal motivated by combining expressiveness timeline representation with decomposition methods Hierarchical Task Networks (HTN). Our current focus not efficient temporal per se, but tight integration planning. addressed by: (i) extending HTN refinement planned actions skills, expressed in PRS, to map into low-level commands, (ii)...
Metal-support interactions at the Pt/Co<sub>3</sub>O<sub>4</sub>(111) interface yield Pt<sup>δ+</sup> species which control stability of supported nanoparticles.
Smallest metallic (blue) and ionic (grey) Pt objects on ceria are shaped controlled by surface oxygen content.