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    Physicochemical Properties of Tungsten Trioxide Photoanodes Fabricated by Wet Coating of Soluble, Particulate, and Mixed Precursors
    (MDPI, 2024-02-01) Chittoory, Valli Kamala Laxmi Ramya; Filipská, Markéta; Bartoš, Radim; Králová, Marcela; Dzik, Petr
    Advanced oxidation processes are emerging technologies for the decomposition of organic pollutants in various types of water by harnessing solar energy. The purpose of this study is to examine the physicochemical characteristics of tungsten(VI) oxide (WO3) photoanodes, with the aim of enhancing oxidation processes in the treatment of water. The fabrication of WO3 coatings on conductive fluorine-doped tin oxide (FTO) substrates was achieved through a wet coating process that utilized three different liquid formulations: a dispersion of finely milled WO3 particles, a fully soluble WO3 precursor (acetylated peroxo tungstic acid), and a combination of both (applying a brick-and-mortar strategy). Upon subjecting the WO3 coatings to firing at a temperature of 450 degrees C, it was observed that their properties exhibited marked variations. The fabricated photoanodes are examined using a range of analytical techniques, including profilometry, thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), and voltammetry. The experimental data suggest that the layers generated through the combination of particulate ink and soluble precursor (referred to as the brick-and-mortar building approach) display advantageous physicochemical properties, rendering them suitable for use as photoanodes in photoelectrochemical cells.
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    Novel highly stable conductive polymer composite PEDOT:DBSA for bioelectronic applications
    (Springer Nature, 2023-05-15) Tumová, Šárka; Malečková, Romana; Kubáč, Lubomír; Akrman, Jiří; Enev, Vojtěch; Kalina, Lukáš; Šafaříková, Eva; Pešková, Michaela; Víteček, Jan; Vala, Martin; Weiter, Martin
    In this work, a novel conductive polymer composite PEDOT:DBSA for bioelectronic applications was prepared and optimized. The novel PEDOT:DBSA composite possesses superior biocompatibility toward cell culture and electrical characteristics comparable to the widely used PEDOT:PSS. The cross-linking processes induced by the cross-linker GOPS, which was investigating in detail using Fourier transform Raman spectroscopy and XPS analysis, lead to the excellent long-term stability of PEDOT:DBSA thin films in aqueous solutions, even without treatment at high temperature. The electrical characteristics of PEDOT:DBSA thin films with respect to the level of cross-linking were studied in detail. The conductivity of thin films was significantly improved using sulfuric acid posttreatment. A model transistor devicebased on PEDOT:DBSA shows typical transistor behavior and suitable electrical properties comparable or superior to those of avaible conductive polymers in bioelectronics, such as PEDOT:PSS. Based on these properties, the newly developed material is well suitable for bioelectronic applications that require long-term contact with living organisms, such as wearable or implantable bioelectronics.
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    Photocatalytic Microplastics "On-The-fly" Degradation via Motile Quantum Materials-Based Microrobots
    (Wiley-VCH, 2023-05-16) Jančík Procházková, Anna; Jašek, Vojtěch; Figalla, Silvestr; Pumera, Martin
    Nano/micro-plastics pollution is an emerging global concern. A variety of biodegradable polymers have been synthesized to enhance the degradation of plastic materials and thereby avoid their accumulation in the environment. However, even biodegradable polymers can accumulate in environments under specific conditions and present a potential hazard. Here, antimony sulfide-based microrobots decorated with magnetite nanoparticles are designed for microplastics degradation. The propulsion of microrobots is enabled by two independent orthogonal physical modes via magnetic field and via light irradiation. Due to phoretic interactions, the microrobots exhibit affinity toward poly(3-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) microplastics, which enables subsequent transport of the microplastics in a transversal rotating magnetic field. The photocatalytic activity of Sb2S3 quantum material provides microrobots with the ability to degrade the microplastics under UV light irradiation in the "on-the-fly" regime without the need for any fuel. This proof-of-concept work shows efficient capture, transport, and photocatalytic degradation of microplastics and paves the way toward their elimination, especially in water environments.
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    Density of bulk trap states of hybrid lead halide perovskite single crystals: temperature modulated space-charge-limited-currents
    (Springer Nature, 2019-03-04) Pospíšil, Jan; Zmeškal, Oldřich; Nešpůrek, Stanislav; Krajčovič, Jozef; Weiter, Martin; Kovalenko, Alexander
    Temperature-modulated space-charge-limited-current spectroscopy (TMSCLC) is applied to quantitatively evaluate the density of trap states in the band-gap with high energy resolution of semiconducting hybrid lead halide perovskite single crystals. Interestingly multicomponent deep trap states were observed in the pure perovskite crystals, which assumingly caused by the formation of nanodomains due to the presence of the mobile species in the perovskites.
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    Ohlas od Nežárky a jeho podíl na poznání regionální a lokální historie na příkladu dějin Stráže nad Nežárkou a pánů ze Stráže
    (Národní muzeum, 2023-02-17) Maráz, Karel
    Ohlas od Nežárky byl jedním z nejdéle vycházejících regionálních kulturních týdeníků. Jednalo se o periodikum pro poučení i zábavu, které věnovalo značnou pozornost (nejen regionální a místní) historii. Vzhledem k vysoké kvalitě různorodých textů, které v něm publikovali nejrůznější odborníci a znalci, je zmiňován například v Přehledných dějinách českého a slovenského dějepisectví. Soupis článků z jednotlivých čísel regionálního masmédia z dané doby již byl publikován, ale dosud postrádáme podrobné rozbory jeho textů k vybraným lokalitám a problémům. Patří k nim například historie Stráže nad Nežárkou, která nebyla zpracována v žádné moderně koncipované publikaci, a osudy pánů modré pětilisté růže. Oběma se autor ve svém článku věnuje. Analyzuje obsah publikovaných textů ke konkrétním otázkám a jejich vypovídací hodnotu v dobovém kontextu a ve světle poznatků současných historických disciplín. Upozorňuje také na informační, metodologické, žánrové a formální přístupy jednotlivých přispěvatelů.