Horizont 2020
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/54581
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Článek Otevřený přístup peer-reviewedpublished version Investigating “Man’s Relation to Reality”: Peter Winch, the Vanishing Shed and Metaphysics after Wittgenstein(Wiley-Blackwell, 2022) Lagerspetz, OlliPeter Winch believed that the central task of philosophy was toinvestigate ‘the force of the concept of reality’ in human practices. Thisinvolved creative dialogue with critical metaphysics. In ‘Ceasing toExist’, Winch considered what it means to judge that somethingunheard-of has happened. Referring to Wittgenstein, Winch argued thatjudgments concerning reality must relate our observations to a shared‘flow of life’. This implies criticism of the form of epistemologyassociated with metaphysical realism. Just as, according to Wittgenstein, asentence has no fixed meaning in isolation, an observation does notconstitute knowledge outside shared human practices.Článek Otevřený přístup peer-reviewedThis is a postprint of an article published in RSC Advances. The final authenticated version is available online at: https://doi.org/10.1039/D0RA02929G or https://pubs.rsc.org/en/Content/ArticleLanding/2020/RA/D0RA02929G#!divAbstract Laser-induced crystallization of anodic TiO2 nanotube layers(Royal Society of Chemistry, 2020) Sopha, Hanna; Mirza, Inam; Turčičova, Hana; Pavliňák, David; Michalicka, Jan; Krbal, Miloš; Rodriguez Pereira, Jhonatan; Hromádko, Luděk; Novák, Ondřej; Mužík, Jiří; Smrž, Martin; Kolibalova, Eva; Goodfriend, Nathan; Bulgakova, Nadezhda M.; Mocek, Tomas; Macak, JanIn this study, crystallization of amorphous TiO2 nanotube (TNT) layers upon optimized laser annealing is shown. The resulting anatase TNT layers do not show any signs of deformation or melting. The crystallinity of the laser annealed TNT layers was investigated using X-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM). The study of the (photo-)electrochemical properties showed that the laser annealed TNT layers were more defective than conventional TNT layers annealed in a muffle oven at 400 °C, resulting in a higher charge recombination rate and lower photocurrent response. However, a lower overpotential for hydrogen evolution reaction was observed for the laser annealed TNT layer compared to the oven annealed TNT layer.Článek Otevřený přístup peer-reviewedThis is a postprint of an article published in Advanced Materials Interfaces. The final authenticated version is available online at: https://doi.org/10.1002/admi.201701146 or https://onlinelibrary.wiley.com/doi/abs/10.1002/admi.201701146 MoSexOy-Coated 1D TiO2 Nanotube Layers: Efficient Interface for Light-Driven Applications(Wiley-Blackwell, 2018) Ng, Siowwoon; Krbal, Miloš; Zazpe, Raul; Prikryl, Jan; Charvot, Jaroslav; Dvořák, Filip; Strizik, Lukas; Slang, Stanislav; Sopha, Hanna; Kosto, Yuliia; Matolin, Vladimir; Yam, Fong Kwong; Bures, Filip; Macak, JanUltrathin molybdenum oxyselenide (MoSexOy) coatings were made first ever by atomic layer deposition (ALD) within anodic 1D TiO2 nanotube layers for photoelectrochemical and photocatalytic applications. The coating thickness was controlled through varying ALD cycles from 5 to 50 cycles (corresponding to ~1 to 10 nm). In the ultraviolet region, the coatings have enhanced up to 4 times the incident photon to current conversion efficiency (IPCE), and the highest IPCE was recorded at 32% at (at λ = 365 nm). The coatings notably extended the photoresponse to the visible spectral region and remarkable improvement of photocurrent densities up to ~40 times was registered at λ = 470 nm. As a result, the MoSexOy coated-TiO2 nanotube layers have shown to be an effective photocatalyst for methylene blue (MB) degradation, and the optimal performance was credited to a coating thickness between 2 to 5 nm (feasible only by ALD). The enhancement in photo-activities of the presented heterojunction is mainly associated with the passivation effect of MoSexOy on the TiO2 nanotube walls and the suitability of bandgap position between MoSexOy and TiO2 interface for an efficient charge transfer. In addition, MoSexOy possesses a narrow bandgap, which favors the photoactivity in the visible spectral region.Článek Otevřený přístup peer-reviewedThis is a postprint of an article published in Frontiers in Chemistry. The final authenticated version is available online at: https://doi.org/10.3389/fchem.2019.00038 or https://www.frontiersin.org/articles/10.3389/fchem.2019.00038/full TiO2 ALD coating of amorphous TiO2 nanotube layers: Inhibition of the structural and morphological changes due to water annealing(Frontiers Media S.A., 2020) Ng, Siowwoon; Sopha, Hanna; Zazpe, Raul; Spotz, Zdenek; Bijalwan, Vijay; Dvorak, Filip; Hromádko, Luděk; Přikryl, Jan; Macák, JanThe present work presents a strategy to stabilize amorphous anodic self-organized TiO2 nanotube layers against morphological changes and crystallization upon extensive water soaking. The growth of needle-like nanoparticles was observed on the outer and inner walls of amorphous nanotube layers after extensive water soakings, in line with the literature on water annealing. In contrary, when TiO2 nanotube layers uniformly coated by thin TiO2 using atomic layer deposition (ALD) were soaked in water, the growth rates of needle-like nanoparticles were substantially reduced. We investigated the soaking effects of ALD TiO2 coatings with different thicknesses and deposition temperatures. Sufficiently thick TiO2 coatings (≈8.4 nm) deposited at different ALD process temperatures efficiently hamper the reactions between water and F- ions, maintain the amorphous state and preserve the original tubular morphology. This work demonstrates the possibility of having robust amorphous 1D TiO2 nanotube layers that are very stable in water. This is very practical for diverse biomedical applications that are accompanied by extensive contact with an aqueous environment.Článek Otevřený přístup peer-reviewedThis is a postprint of an article published in Electrochimica Acta. The final authenticated version is available online at: https://doi.org/10.1016/j.electacta.2020.136479 or https://www.sciencedirect.com/science/article/pii/S0013468620308720 Intrinsic properties of high-aspect ratio single- and double-wall anodic TiO2 nanotube layers annealed at different temperatures(Elsevier, 2020) Motola, Martin; Hromádko, Luděk; Přikryl, Jan; Sopha, Hanna; Krbal, Milos; Macak, JanIn this work, we present the influence of thermal annealing on morphological, structural, electrical, optical, and photoelectrochemical properties of double- (DW) and single-wall (SW) TiO2 nanotube (TNT) layers. High-aspect ratio TNT layers with a thickness of ~5 µm and ~20 µm with an average inner diameter of ~250 nm and ~130 nm, respectively, were prepared via electrochemical anodization of Ti foil in two different fluoride containing ethylene glycol-based electrolytes. The inner wall of the native DW TNT layers was quantitatively removed via a mild pre-annealing followed by a selective etching treatment in piranha solution, yielding SW TNT layers. The obtained SW TNT layers annealed at 300 – 500 °C possess enhanced conductivity by 1 – 2 orders compared to their DW counterparts. The photoelectrochemical properties of SW TNT layers are enhanced compared to their DW counterparts in the annealing temperature range 300 – 800 °C. In principle, the SW TNT layers could be potentially favored to the DW TNT layers in electrical and photoelectrochemical applications due to their more superior intrinsic properties.Článek Otevřený přístup peer-reviewedThis is a postprint of an article published in FlatChem. The final authenticated version is available online at: https://doi.org/10.1016/j.flatc.2020.100166 or https://www.sciencedirect.com/science/article/pii/S2452262720300155 Atomic Layer Deposition of MoSe2 Using New Selenium Precursors(Elsevier, 2020) Zazpe, Raul; Charvot, Jaroslav; Krumpolec, Richard; Hromádko, Luděk; Pavliňák, David; Dvorak, Filip; Knotek, Petr; Michalicka, Jan; Přikryl, Jan; Ng, Siowwoon; Jelínková, Veronika; Bureš, Filip; Macák, JanAmong the emerging 2D materials, transition metal chalcogenides are particularly encouraging as alternative semiconducting graphene-like nanomaterial. Recently, 2D MoSe2 has been gaining interest due to its intriguing properties, in many ways exceeding those of the extensively studied MoS2. The deposition of 2D nanomaterials in a conformal and uniform fashion on complex-shaped nanostructures is highly appealing but only achievable by atomic layer deposition (ALD). Unfortunately, the synthesis of MoSe2 by ALD is hindered by a current substantial lack of feasible Se precursors. In this work, we synthesized a set of alkysilyl (R3Si)2Se and alkylstannyl (R3Sn)2Se compounds and studied their suitability as Se ALD precursors. Thus, ALD processes carried out using MoCl5 as Mo precursor counterpart were followed by an extensive characterization of the as deposited material. The corresponding results revealed successful deposition of MoSe2 nanostructures on substrates of different nature with dominant out-of-plane orientation. Eventually, the growth evolution of the MoSe2 during the very early ALD stage was studied and described, displaying concomitant in-plane and out-of-plane MoSe2 growth. All in all, a set of Se suitable precursors presented herein paves the way for the deposition of 2D MoSe2 with all the own ALD benefits and allow the further study of its promising properties in a wide number of applications.Článek Otevřený přístup peer-reviewedpublished Amorphous TiO2 Nanotubes as a Platform for Highly Selective Phosphopeptide Enrichment(American Chemical Society, 2019-07-15) Kupčík, Rudolf; Macák, Jan; Rehulkova, Helena; Sopha, Hanna; Fabrik, Ivo; Anitha, V. C.; Klimentova, Jana; Murasová, Pavla; Bílková, Zuzana; Rehulka, PavelThis work reports highly selective phosphopeptide enrichment using amorphous TiO2 nanotubes (TiO2NTs) and the same material decorated with superparamagnetic Fe3O4 nanoparticles (TiO2NTs@Fe3O4NPs). TiO2NTs and TiO2NTs@Fe3O4NPs materials were applied for phosphopeptide enrichment both from a simple peptide mixture (tryptic digest of bovine serum albumin and α-casein) and from a complex peptide mixture (tryptic digest of Jurkat T cell lysate). The obtained enrichment efficiency and selectivity for phosphopeptides of TiO2NTs and TiO2NTs@Fe3O4NPs were increased to 28.7 and 25.3%, respectively, as compared to those of the well-established TiO2 microspheres. The enrichment protocol was extended for a second elution step facilitating the identification of additional phosphopeptides. It further turned out that both types of amorphous TiO2 nanotubes provide qualitatively new physicochemical features that are clearly advantageous for highly selective phosphopeptide enrichment. This has been confirmed experimentally resulting in substantial reduction of non-phosphorylated peptides in the enriched samples. In addition, TiO2NTs@Fe3O4NPs combine high selectivity and ease of handling due to the superparamagnetic character of the material. The presented materials and performances are further promising for applications toward a whole range of other types of biomolecules to be treated in a similar fashion.Článek Otevřený přístup peer-reviewedaccepted version ALD SnO2 coated anodic 1D TiO2 nanotube layers for low concentration NO2 sensing(2020-06-26) Ng, Siowwoon; Prášek, Jan; Zazpe, Raul; Pytlíček, Zdeněk; Spotz, Zdenek; Rodriguez Pereira, Jhonatan; Michalička, Jan; Přikryl, Jan; Krbal, Miloš; Sopha, Hanna; Hubálek, Jaromír; Macák, JanThe continuous emission of nitrous oxides contributes to the overall air pollution and deterioration of air quality. In particular, an effective NO2 sensor capable of low concentration detection for continuous monitoring is demanded for safety, health, and wellbeing. The sensing performance of a metal oxide based sensor is predominantly influenced by the availability of surface area for O2 adsorption and desorption, efficient charge transport and size or thickness of the sensing layer. In this study, we utilized anodic one-dimensional (1D) TiO2 nanotube layers of 5 µm thick which offer large surface area and unidirectional electron transport pathway as a platform to accommodate thin SnO2 coatings as a sensing layer. Conformal and homogeneous SnO2 coatings across the entire inner and outer TiO2 nanotubes were achieved by atomic layer deposition with controlled thickness of 4, 8 and 16 nm. The SnO2 coated TiO2 nanotube layers attained a higher sensing response than a reference Figaro SnO2 sensor. Specifically, the 8 nm SnO2 coated TiO2 nanotube layer has recorded up to ten-fold enhancement in response as compared to the blank nanotubes for the detection of 1 ppm NO2 at the operating temperature of 300 oC with 0.5 V applied bias. This is attributed to the SnO2/TiO2 heterojunction effect and controlled SnO2 thickness within the range of the Debye length. We demonstrated in this work, a tailored large surface area platform based on 1D nanotubes with thin active coatings as an efficient approach for sensing applications and beyond.Článek Otevřený přístup peer-reviewedpostprint Self-supported sulphurized TiO2 nanotube layers as positive electrodes for lithium microbatteries(Elsevier, 2019-06-14) Salian, Girish D.; Krbal, Miloš; Sopha, Hanna; Lebouind, Chrystelle; Coulet, Marie-Vanessa; Michalička, Jan; Hromádko, Luděk; Tesfayea, Alexander T.; Macák, Jan; Djeniziana, ThierryWe report the synthesis and characterization of self-supported sulphurized TiO2 nanotube layers as a cathode material for Li microbatteries. Sulphurized TiO2 nanotubes were obtained by annealing of self-supported TiO2 nanotubes in sulphur atmosphere. The morphology, structure, composition and thermal stability of the TixOySz nanotube layers were studied by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and thermogravimetric analysis. The electrochemical behaviors of the chemically modified nanotubes were investigated by cyclic voltammetry and chronopotentiometry techniques. This nanostructured electrode used as a cathode material showed high rate capabilities even at very fast kinetics. Remarkably, a high discharge capacity (340 μAh cm−2) has been retrieved after 100 cycles with 100% coulombic efficiency attesting the excellent stability of the electrode.Článek Otevřený přístup peer-reviewedpostprint Fabrication of TiO2 nanotubes on Ti spheres using bipolar electrochemistry(Elsevier, 2020-01-24) Sopha, Hanna; Hromádko, Luděk; Motola, Martin; Macák, JanIn this work, the anodization of Ti spheres using bipolar electrochemistry is reported for the first time. TiO2 nanotubes were found over the entire surface area of the Ti spheres when a square-wave potential was employed. The TiO2 nanotubes were ∼77 nm in inner diameter and had a thickness of ∼2 µm on the extremities of the Ti spheres. Due to their increased surface area, the Ti spheres covered with TiO2 nanotubes had a rate constant for the photocatalytic degradation of methylene blue which was approximately 2.15 times higher than that of non-anodized Ti spheres with a thin thermal oxide layer.