Michal Otyepka

Michal Otyepka
Palacký University Olomouc · Regional Centre of Advanced Technologies and Materials

professor, PhD

About

426
Publications
92,596
Reads
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19,955
Citations
Additional affiliations
April 2021 - present
Palacký University Olomouc
Position
  • Group Leader
January 2021 - present
Palacký University Olomouc
Position
  • Head of Department
June 2019 - December 2020
Palacký University Olomouc
Position
  • Research Director

Publications

Publications (426)
Article
We present a combined experimental and theoretical quantification of the adsorption enthalpies of seven organic molecules (acetone, acetonitrile, dichloromethane, ethanol, ethylacetate, hexane, and toluene) on graphene. Adsorption enthalpies were measured by inverse gas chromatography and ranged from -5.9 kcal/mol for dichloromethane to -13.5 kcal/...
Article
Fluorographene (FG) is a two-dimensional graphene derivative with promising application potential; however, its reactivity is not understood. We have systematically explored its reactivity in vacuum and polar environments. The C−F bond dissociation energies for homo-and heterolytic cleavage are above 100 kcal/mol, but the barrier of S N 2 substitut...
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Graphene has attracted great interest because of its remarkable properties and numerous potential applications. A comprehensive understanding of its structural and dynamic properties and those of its derivatives will be required to enable the design and optimization of sophisticated new nanodevices. While it is challenging to perform experimental s...
Article
Efficient and selective methods for covalent derivatization of graphene are needed because they enable tuning of graphene’s surface and electronic properties, thus expanding its application potential. However, existing approaches based mainly on chemistry of graphene and graphene oxide achieve only limited level of functionalization due to chemical...
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Single‐atom catalysts (SACs) aim at bridging the gap between homogeneous and heterogeneous catalysis. The challenge is the development of materials with ligands enabling coordination of metal atoms in different valence states, and preventing leaching or nanoparticle formation. Graphene functionalized with nitrile groups (cyanographene) is herein em...
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Single-atom catalysts (SACs) based on graphene derivatives are an emerging and growing class of materials functioning as two-dimensional (2D) metal-coordination scaffolds with intriguing properties. Recently, owing to the rich chemistry of fluorographene, new avenues have opened toward graphene derivatives with selective, spacer-free, and dense fun...
Article
Inorganic electrides have been proved to be efficient hosts for incorporating transition metals, which can effectively act as active sites giving an outstanding catalytic performance. Here, it is demonstrated that a reusable and recyclable (for more than 7 times) copper-based intermetallic electride catalyst (LaCu0.67 Si1.33 ), in which the Cu site...
Article
MXenes, a class of two-dimensional (2D) materials, are synthesized by etching MAX phase precursors to produce multilayer MXenes, where individual 2D sheets are held together by van der Waals forces. Typically, single 2D flakes of MXene are produced by chemical intercalation to delaminate multilayer MXenes, which is a time-intensive process that pro...
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Since the groundbreaking discovery of graphene by Geim and Novoselov in 2004, there has been continuous research focused on the utilization of graphene (GR) and graphene-related materials (GRms) in technologically high-impact applications, spanning from electronics, sensing, and spintronics, to catalysis, energy storage, and environmental remediati...
Article
Heavy Metal Detection In article number 2201003 by Aristides Bakandritsos, Michal Otyepka, and co‐workers, recyclable fluorescent nanographenes with high‐affinity pockets for toxic metals enable selective and highly effective decontamination of natural water and quality monitoring with sub‐nanomolar sensitivity for lead and cadmium via photolumines...
Article
A metal-free electrocatalyst consisting of a covalently linked graphene–fullerene hybrid material was prepared following the chemistry of fluorographene, displaying improved hydrogen evolution reaction electrocatalytic activity and high durability.
Article
Access to clean water for drinking, sanitation, and irrigation is a major sustainable development goal of the United Nations. Thus, technologies for cleaning water and quality‐monitoring must become widely accessible and of low‐cost, while being effective, selective, sustainable, and eco‐friendly. To meet this challenge, hetero‐bifunctional nanogra...
Article
Electrochemical methanol oxidation reaction (MOR) serves as a key route for renewable energy technologies. However, unmet challenges remain in the preparation of low-cost, efficient and robust electrocatalysts for MOR. Herein, a porphyrinic metal-organic framework (MOF) with spatially isolated Ni centres is prepared. Upon pyrolysis, this affords a...
Article
Graphene derivatives are an emerging and important class of promising materials because they can bear a wide variety of functional groups, rendering them suitable for a plethora of applications, ranging from energy storage to sensorics. Further functionalisation of these materials requires a thorough understanding of their reactivity at the molecul...
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Full-text available
Generally adopted strategies for enhancing the photocatalytic activity are aimed at tuning the visible light response, the exposed crystal facets, and the nanocrystal shape. Here, we present a different approach for designing efficient photocatalysts displaying a substrate-specific reactivity upon defect engineering. The platinized, defective aniso...
Article
Crystallization as one of the final steps in the industrial production of active pharmaceutical ingredients (APIs) significantly influences their physicochemical and rheological properties. Different crystallization procedures including antisolvent crystallization, seeding crystallization, crystallization with templates and sonocrystallization were...
Article
Fluorographene is a fully fluorinated derivative of graphene. Unlike graphene, fluorographene is a wide gap semiconductor/insulator that holds great potential for applications requiring two-dimensional dielectric nanomaterials. Despite growing interest and a well-defined structure, the basic questions of fluorographene’s band gap nature and value r...
Article
Hybrid Materials In article number 2104628, Demetrios D. Chronopoulos, Kolleboyina Jayaramulu, Michal Otyepka, and co‐workers review the integration of carbon nanotubes with metal–organic frameworks into hybrid materials with augmented properties, otherwise difficult to accomplish by a single class of materials. The authors map the growth, structur...
Article
This review article focuses on supercapacitor electrode materials based on composites of metal-organic frameworks (MOFs) and conductive polymers (CPs). MOFs have attracted enormous attention due to their unique properties such as high porosity, nanoscale periodicity, large surface area and structural diversity. The major disadvantage of MOFs for en...
Preprint
Full-text available
Doping of the graphene lattice with transition metal atoms resulting in high magnetic anisotropy energy (MAE) is an important goal of materials research owing to its potential application in spintronics. In this article, by using spin-polarized density functional theory including spin-orbit coupling, we examined magnetic properties of graphene with...
Article
Supercapacitors have attracted great interest because of their fast, reversible operation and sustainability. However, their energy densities remain lower than those of batteries. In the last decade, supercapacitors with an energy content of ∼110 W h L-1 at a power of ∼1 kW L-1 were developed by leveraging the open framework structure of graphene-r...
Article
Oil contaminated water is a global issue, decreasing the quality of water sources and is posing a threat to the health of humans and many ecosystems. The utilization of industrial...
Article
Environmentally sustainable, low-cost, flexible, and lightweight energy storage technologies require advancement in materials design in order to obtain more efficient organic metal-ion batteries. Synthetically tailored organic molecules, which react reversibly with lithium, may address the need for cost-effective and eco-friendly anodes used for or...
Article
Metal–organic frameworks (MOFs) materials constructed by the coordination chemistry of metal ions and organic ligands are important members of the crystalline materials family. Owing to their exceptional properties, for example, high porosity, tunable pore size, and large surface area, MOFs have been applied in several fields such as gas or liquid...
Article
Background and purpose: Opioids and benzodiazepines are frequently combined in medical as well as in non-medical contexts. At high doses, such combinations often result in serious health complications attributed to pharmacodynamics interactions. Here, we investigate the contribution of the metabolic interactions between oxycodone, diazepam and dic...
Preprint
Atomistic molecular dynamics (MD) simulations represent established technique for investigation of RNA structural dynamics. Despite continuous development, contemporary RNA simulations still suffer from suboptimal accuracy of empirical potentials (force fields, ffs) and sampling limitations. Development of efficient enhanced sampling techniques is...
Article
Recent advances in RNA-based medicine have provided new opportunities for the global current challenge, i.e., the COVID-19 pandemic. Novel vaccines are based on a messenger RNA (mRNA) motif with a lipid nanoparticle (LNP) vector, consisting of high content of unique pH-sensitive ionizable lipids (ILs). Here we provide molecular insights into the ro...
Article
Emerging experimental evidence suggests tau pathology spreads between neuroanatomically connected brain regions in a prion‐like manner in Alzheimer's disease (AD). Tau seeding, the ability of prion‐like tau to recruit and misfold naïve tau to generate new seeds, is detected early in human AD brains before the development of major tau pathology. Man...
Article
With the increased demand for beef in emerging markets, the development of quality-control diagnostics that are fast, cheap and easy to handle is essential. Especially where beef must be free from pork residues, due to religious, cultural or allergic reasons, the availability of such diagnostic tools is crucial. In this work, we report a label-free...
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Full-text available
Owing to their low cost, good performance, and high lifetime stability, activated carbons (ACs) with a large surface area rank among the most popular materials deployed in commercially available electrochemical double-layer (EDLC) capacitors. Here, we report a simple two-step synthetic procedure for the preparation of activated carbon from natural...
Article
Practical‐scale on‐site production of hydrogen peroxide (H 2 O 2 ) via two‐electron (2e – ) oxygen reduction reaction (ORR) relies on efficient, robust, and selective electrocatalysts. Among them, carbon‐based materials are cheap, abundant, durable, and their surface properties can be tuned to favour the 2e – ORR pathways, resulting in higher effic...
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Sulfur represents a low‑cost, sustainable, and high theoretical capacity cathode material for lithium–sulfur batteries, which can meet the growing demand in portable power sources, such as in electric vehicles and mobile information technologies. However, the shuttling effect of the formed lithium polysulfides, as well as their low conductivity, co...
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Full-text available
Sulfur is a promising material for electrochemical energy storage but is hampered by its low conductivity and dissolution during battery charging/discharging. In article number 2101326, Aristides Bakandritsos, Radek Zboril, Michal Otyepka, and co‐workers, by exploiting the chemistry of fluorographene and the reactivity of sodium polysulfides, achie...
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Eco‐friendly, electrochemically active electrode materials based on covalent graphene derivatives offer enormous potential for energy storage applications. However, covalent grafting of functional groups onto graphene’s surface is challenging due to its low reactivity. We employed fluorographene chemistry to graft an arginine moiety via its guanidi...
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The ability of bacteria to develop resistance to antibiotics is threatening one of the pillars of modern medicine. It was recently understood that bacteria can develop resistance even to silver nanoparticles by starting to produce flagellin, a protein which induces their aggregation and deactivation. This study shows that silver covalently bound to...
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Silver covalently bound to cyanographene overcomes bacterial‐resistance mechanisms to silver nanoparticles, eliminating such highly persistent microorganisms at concentrations thirty times lower than free silver nanoparticles. The strong covalent bonding of silver clusters to the graphenebased 2D matrix imparts very high cytocompatibility compared...
Article
The shortage of fossil fuels and burgeoning global warming has increased the demand for clean energy making biodiesel a promising alternative to conventional fuels. Heterogeneous catalysis plays a vital role in the cost-effectiveness of the expensive conventional biodiesel synthesis via transesterification reactions between lipid feedstocks such as...
Article
Exposed surfaces of two-dimensional (2D) materials are susceptible to the adsorption of various molecules including airborne contaminants, which can affect their performance in real applications. Hexagonal boron nitride (hBN) is structurally the closest relative to graphite and its single layer form to graphene. The adsorption of organic molecules...
Article
Graphene derivatives can work as a suitable support anchoring metal atoms and ions, which can be utilized as stable and lightweight single‐atom catalysts (SACs). Computational chemistry aids to design such graphene‐based SACs, providing insights into their stability and reactivity, which can push the limits of this burgeoning field. More details ca...
Article
Single‐atom catalysts (SACs) have aroused great attention due to their high atom efficiency and unprecedented catalytic properties. A remaining challenge is to anchor the single atoms individually on support materials via strong interactions. Herein, single atom Co sites have been developed on functionalized graphene by taking advantage of the stro...
Article
Highly fluorescent carbon nanoparticles called carbon dots (CDs) have been the focus of intense research due to their simple chemical synthesis, nontoxic nature, and broad application potential including optoelectronics, photocatalysis, biomedicine, and energy-related technologies. Although a detailed elucidation of the mechanism of their photolumi...
Article
Carbon dots (CDs), including graphene quantum dots, carbon nanodots, carbon quantum dots, and carbonized polymer dots, belong to extensively studied nanomaterials with a very broad application potential resulting from their bright photoluminescence (PL), high (photo)stability, low toxicity and great biocompatibility. However, the design of CDs with...
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Potassium‐ion batteries (KIBs) have attracted enormous attention as next‐generation energy storage system due to their low‐cost, fast ionic conductivity within the electrolyte and high operating voltage. However, the developing suitable electrode materials to guarantee high‐energy output and structural stability to ensure long cycling performance r...
Article
The ever decreasing sources of fossil fuels have launched extensive research of alternative materials that might play a key role in their replacement. Therefore, the scientific community continuously investigates the possibilities of maximizing the working capacity of such materials in order to fulfill energy challenges in the near future. In this...
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Guanine quadruplex nucleic acids (G4s) are involved in key biological processes such as replication or transcription. Beyond their biological relevance, G4s find applications as biotechnological tools since they readily bind hemin and enhance its peroxidase activity, creating a G4-DNAzyme. The biocatalytic properties of G4-DNAzymes have been thorou...
Article
Full-text available
In this work, the covalent attachment of an amine functionalized metal‐organic framework (UiO‐66‐NH2 = Zr6O4(OH)4(bdc‐NH2)6; bdc‐NH2 = 2‐amino‐1,4‐benzenedicarboxylate) (UiO‐Universitetet i Oslo) to the basal‐plane of carboxylate functionalized graphene (graphene acid = GA) via amide bonds is reported. The resultant GA@UiO‐66‐NH2 hybrid displayed a...
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In article number 2004560, Kolleboyina Jayaramulu, Deepak Dubal, Radek Zboril, Roland A. Fischer, and co‐workers report covalent attachment of graphene acid (GA) and an amine‐functionalized metal–organic framework (UiO‐66‐NH2) via the amide bond. The hybrid GA@UiO‐66‐NH2 acts as an effective charge‐storing material with a remarkable capacitance. Th...
Article
Sorption technologies, enabling removal of heavy metals, play a pivotal role in meeting the global demands for unrestricted access to drinking water. Standard sorption technologies suffer from limited efficiency related to the weak sorbent-metal interaction. Further challenges include the development of technologies enabling smart metal recovery an...
Preprint
Full-text available
Single‐atom catalysts (SACs) are highly enviable to exploit the utmost utilization of metallic catalysts; their efficiency by utilizing nearly all atoms to often exhibit high catalytic performances. To architect the isolated single atom on an ideal solid support with strong coordination has remained a crucial trial. Herein, graphene functionalized...
Article
Detectors with rapid detection time, low detection limits, high selectivity and sensitivity towards CO2 gas are important for health and safety applications for instance in the food industry and to...
Article
Superhydrophobic MOF-nanosheets assembled on the outside of an aqueous droplet form ‘liquid marbles’. A facile mechanochemical-based synthesis followed by ultrasonication was used to prepare two-dimensional superhydrophobic-oleophilic MOF nanosheets of a...
Article
Explicit solvent atomistic molecular dynamics (MD) simulations represent an established technique to study structural dynamics of RNA molecules and an important complement for diverse experimental methods. However, performance of molecular mechanical (MM) force fields (ff's) remains far from satisfactory even after decades of development, as appare...
Article
Tantalum disulphide belongs to the group of transition metal dichalcogenides (TMDs) and has attracted attention for its unique structural, electronic, and catalytic properties. Herein, we report the edge properties of single-layer 2H-TaS2 studied by using density functional theory calculations, because the knowledge of the edge morphology, stabilit...
Preprint
Full-text available
Guanine quadruplex nucleic acids (G4s) are involved in key biological processes such as replication or transcription. Beyond their biological relevance, G4s find applications as biotechnological tools since they readily bind hemin and enhance its peroxidase activity, creating a G4-DNAzyme. The biocatalytic properties of G4-DNAzymes have been thorou...
Article
Graphene derivatives with anchored metal atoms represent a promising class of single‐atom catalysts (SACs). To elucidate factors determining the bond strength between metal atoms and graphene derivatives, a series of late 3d and 4d elements, including the iron triad, light platinum group elements, and coinage metals (Fe, Co, Ni, Ru, Rh, Pd, Cu, Ag,...
Article
In article number 2004891, Roland A. Fischer, Kolleboyina Jayaramulu, and co‐workers present a few strategies reported for synthesizing hybrid MOFs by encapsulating various perovskite halides (hybrids denoted as MHP@MOF). The resultant hybrids show enhanced properties including synergic features such as long‐term stability under moisture, water, co...
Article
Full-text available
Fluorographene (FG) is an uprising member of the graphene family as it combines high reactivity and stability. It presents various types of CF bonds (covalent, semi‐ionic, and ionic bonds) depending on its F‐atom content, which can be efficiently controlled by means of chemical synthesis. It is found that the chemical tweaking of the FG's structur...
Article
Metal halide perovskites (MHPs) have excellent optoelectronic and photovoltaic applications because of their cost‐effectiveness, tunable emission, high photoluminescence quantum yields, and excellent charge carrier properties. However, the potential applications of the entire MHP family are facing a major challenge arising from its weak resistance...