@article{MTMT:32327556, title = {Synthesis and Characterization of Graphite Oxide Derived TiO2-Carbon Composites as Potential Electrocatalyst Supports}, url = {https://m2.mtmt.hu/api/publication/32327556}, author = {Ayyubov, Ilgar and Borbáth, Irina and Pászti, Zoltán and Sebestyén, Zoltán and Mihály, Judith and Szabó, Tamás and Nyergesné Illés, Erzsébet and Domján, Attila and Florea, Mihaela and Radu, Dana and Kuncser, Andrei and Tompos, András and Tálas, Emília}, doi = {10.1007/s11244-021-01513-1}, journal-iso = {TOP CATAL}, journal = {TOPICS IN CATALYSIS}, unique-id = {32327556}, issn = {1022-5528}, abstract = {TiO2-C (carbon) hybrid materials are promising electrocatalyst supports because the presence of TiO2 results in enhanced stability. Use of new types of carbonaceous materials such as reduced graphene oxide instead of traditional active carbon provides certain benefits. Although the rutile polymorph of TiO2 seems to have the most beneficial properties in these hybrid materials, the anatase type is more frequent in TiO2-rGO composites, especially in graphite oxide (GO) derived ones, as GO has several properties which may interfere with rutile formation. To explore and evaluate these peculiarities and their influence on the composite formation, we compared TiO2-C systems formulated with GO and Black Pearls (BP) carbon. Various physicochemical methods, such as attenuated total reflection infrared (ATR-IR)-, solid state NMR-, Raman- and X-ray photoelectron spectroscopy, X-ray powder diffraction (XRD), electron microscopy, etc. were used to characterize the samples from the different stages of our multistep sol–gel synthesis. Our experiments demonstrated that utilization of GO is indeed feasible for composite preparation, although its sodium contamination has to be removed during the synthesis. On the other hand, high temperature treatment and/or solvothermal treatment during composite synthesis resulted in decomposition of the functional groups of the GO and the functional properties of the final product were similar in case of both composites. However, Pt/TiO2-GO derived sample showed higher oxygen reduction reaction activity than Pt/TiO2-BP derived one. Based on the decrease of electrochemical surface area, the stability order was the following: Pt/C (commercial) < Pt/TiO2-BP derived C < Pt/TiO2-GO derived C. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.}, year = {2024}, eissn = {1572-9028}, orcid-numbers = {Szabó, Tamás/0000-0001-8182-640X; Nyergesné Illés, Erzsébet/0000-0002-2901-9616; Florea, Mihaela/0000-0002-6612-6090} } @article{MTMT:34088284, title = {Reductive Treatment of Pt Supported on Ti0.8Sn0.2O2-C Composite: A Route for Modulating the Sn–Pt Interactions}, url = {https://m2.mtmt.hu/api/publication/34088284}, author = {Maria Cristina, Silva Cisneros and Salmanzade, Khirdakhanim and Borbáth, Irina and Dodony, Erzsébet and Olasz, Dániel and Sáfrán, György and Kuncser, Andrei and Pásztiné Gere, Erzsébet and Tompos, András and Pászti, Zoltán}, doi = {10.3390/nano13152245}, journal-iso = {NANOMATERIALS-BASEL}, journal = {NANOMATERIALS}, volume = {13}, unique-id = {34088284}, abstract = {The composites of transition metal-doped titania and carbon have emerged as promising supports for Pt electrocatalysts in PEM fuel cells. In these multifunctional supports, the oxide component stabilizes the Pt particles, while the dopant provides a co-catalytic function. Among other elements, Sn is a valuable additive. Stong metal-support interaction (SMSI), i.e., the migration of a partially reduced oxide species from the support to the surface of Pt during reductive treatment is a general feature of TiO2-supported Pt catalysts. In order to explore the influence of SMSI on the stability and performance of Pt/Ti0.8Sn0.2O2-C catalysts, the structural and catalytic properties of the as prepared samples measured using XRD, TEM, XPS and electrochemical investigations were compared to those obtained from catalysts reduced in hydrogen at elevated temperatures. According to the observations, the uniform oxide coverage of the carbon backbone facilitated the formation of Pt–oxide–C triple junctions at a high density. The electrocatalytic behavior of the as prepared catalysts was determined by the atomic closeness of Sn to Pt, while even a low temperature reductive treatment resulted in Sn–Pt alloying. The segregation of tin oxide on the surface of the alloy particles, a characteristic material transport process in Sn–Pt alloys after oxygen exposure, contributed to a better stability of the reduced catalysts.}, year = {2023}, eissn = {2079-4991}, orcid-numbers = {Maria Cristina, Silva Cisneros/0000-0002-1333-7126; Olasz, Dániel/0000-0003-4136-4612; Sáfrán, György/0000-0003-3708-3551; Kuncser, Andrei/0000-0003-2841-5809} } @article{MTMT:34060723, title = {Continuous-flow regioselective reductive alkylation of oxindole with alcohols and aldehydes in a fast and economical manner}, url = {https://m2.mtmt.hu/api/publication/34060723}, author = {Mándoki, András and Orsy, György and Pászti, Zoltán and Porcs-Makkay, Márta and Bogdán, Dóra and Simig, Gyula and Mándity, István and Volk, Balázs}, doi = {10.1055/a-2122-4080}, journal-iso = {SYNTHESIS-STUTTGART}, journal = {SYNTHESIS-STUTTGART}, volume = {55}, unique-id = {34060723}, issn = {0039-7881}, abstract = {Oxindole is a widely used scaffold in drug discovery, which can be found in several marketed drugs, among them the widely used sunitinib or ziprasidone. Thus, the derivatization of oxindole is of considerable current interest. The extreme reaction conditions (high temperature, high pressure), described in the literature for the batchwise regioselective multistep 3-alkylation of oxindole with alcohols in the presence of Raney nickel, motivated us to develop a robust, time- and cost-efficient continuous-flow variant for this reaction. In addition, the continuous-flow technology was also extended to the reductive 3-alkylation of oxindole with aldehydes. The elaborated methodology allows the safe use of Raney nickel, this cheap and widely applied, albeit pyrophoric catalyst. Under the optimized reaction conditions, 10 oxindole derivatives were synthesized ranging from simple 3-alkyl to 3-aralkyl derivatives including two (trifluoromethyl)benzyl congeners. The technology is considerably robust and the catalyst showed a long-term usability. The model reaction between oxindole and acetaldehyde could be run for 19 h uninterruptedly, rendering possible the efficient ethylation of about 20 g oxindole utilizing only approximately 800 mg of Raney nickel.}, year = {2023}, eissn = {1437-210X}, pages = {4025-4033}, orcid-numbers = {Bogdán, Dóra/0000-0003-4455-8914; Simig, Gyula/0000-0002-2569-6476; Mándity, István/0000-0003-2865-6143; Volk, Balázs/0000-0002-2019-1874} } @article{MTMT:33543145, title = {A study of the conversion of ethanol to 1,3-butadiene: effects of chemical and structural heterogeneity on the activity of MgO-SiO2 mixed oxide catalysts}, url = {https://m2.mtmt.hu/api/publication/33543145}, author = {Szabó, Blanka and Hutkai, V. and Novodárszki, Gyula and Lónyi, Ferenc and Pászti, Zoltán and Fogarassy, Zsolt and Valyon, József and Barthos, Róbert}, doi = {10.1039/d2re00450j}, journal-iso = {REACT CHEM ENG}, journal = {REACTION CHEMISTRY & ENGINEERING}, volume = {8}, unique-id = {33543145}, issn = {2058-9883}, year = {2023}, eissn = {2058-9883}, pages = {718-731}, orcid-numbers = {Fogarassy, Zsolt/0000-0003-4981-1237; Valyon, József/0000-0002-3608-060X} } @article{MTMT:33297776, title = {Nitrogen doped carbonaceous materials as platinum free cathode electrocatalysts for oxygen reduction reaction (ORR)}, url = {https://m2.mtmt.hu/api/publication/33297776}, author = {Ayyubov, Ilgar and Tálas, Emília and Berghian-Grosan, Camelia and Románszki, Loránd and Borbáth, Irina and Pászti, Zoltán and Szegedi, Ágnes and Mihály, Judith and Vulcu, Adriana and Tompos, András}, doi = {10.1007/s11144-022-02331-6}, journal-iso = {REACT KINET MECH CATAL}, journal = {REACTION KINETICS MECHANISMS AND CATALYSIS}, volume = {136}, unique-id = {33297776}, issn = {1878-5190}, abstract = {Comparison of physicochemical properties and electrocatalytic behavior of different N-doped carbonaceous materials as potential catalysts for oxygen reduction reaction (ORR) was attended. Ball-milling of graphite with melamine and solvothermal treatment of graphite oxide, graphene nanoplatelets (GNP) with ammonia were used as preparation methods. Elemental analysis and N 2 physisorption measurements revealed the synthesis of N-doped materials with strongly different morphological parameters. Contact angle measurements proved that all three samples had good wettability properties. According to analysis of XRD data and Raman spectra a higher nitrogen concentration corresponded to a smaller size of crystallites of the N-doped carbonaceous material. Surface total N content determined by XPS and bulk N content assessed by elemental analysis were close, indicating homogenous inclusion of N in all samples. Rotating disc electrode tests showed that these N-doped materials weremuch less active in acidic medium than in an alkaline environment. Although the presence of in-plane N species is regarded to be advantageous for the ORR activity, no particular correlation was found in these systems with any type of N species. According to Koutecky–Levich analysis, both the N-containing carbonaceous materials and the reference Pt/C catalyst displayed a typical one-step, four-electron ORR route. Both ball-milled sample with high N-content but with low SSA and solvothermally synthesized N-GNP with high SSA but low N content showed significant ORR activity. It could be concluded that beside the total N content other parameters such as SSA, pore structure, structural defects, wettability were also essential for achieving high ORR activity.}, year = {2023}, eissn = {1878-5204}, pages = {125-147} } @article{MTMT:33215064, title = {Supercritical carbon dioxide assisted synthesis of ultra-stable sulfur/carbon composite cathodes for Li– S batteries}, url = {https://m2.mtmt.hu/api/publication/33215064}, author = {SHIVA SHANKAR, LAKSHMI and Zalka, Dóra and Szabó, Tamás and Kózelné Székely, Edit and Kőrösi, Márton and Pászti, Zoltán and Balázsi, Katalin and Illés, Levente and Czigány, Zsolt and Kun, Róbert}, doi = {10.1016/j.mtchem.2022.101240}, journal-iso = {MATER TODAY CHEM}, journal = {MATERIALS TODAY CHEMISTRY}, volume = {26}, unique-id = {33215064}, issn = {2468-5194}, abstract = {To mitigate the shuttle effect and enhance the electrical conductivity in lithium battery cathode, the unique characteristics of supercritical CO2 solvent (SC–CO2) and the distinctive porous and layered microstructure of reduced graphene oxide (rGO) are exploited in the fabrication of a high-performance rGO/sulfur composite cathode. Exploiting SC-CO2 technology can realize highly efficient sulfur transfer and precise microstructure regulation of S/C composite cathodes for Li–S batteries. On exposure, due to the sudden pressure release process, the SC-CO2 expands the interlayers of rGO rendering plenty of storage space for small sulfur allotropes in carbon matrices which increases the active sulfur loading. Being a remarkable hydrophobic solvent, the wetting properties of SC-CO2 are excellent, ensuring sulfur dissolution and penetration deep into the voids and interlayers of rGO. This creates intimate contact of sulfur with rGO interlayers, guaranteeing precise sulfur content, uniform sulfur distribution, and strong interaction between sulfur and carbon leading to enhanced electrical conductivity and sulfur utilization efficiency. Another important feature is that the S/C composites can be prepared at room temperature, unlike other conventional techniques which require a higher temperature. Moreover, the product mixture can be separated simply by de-pressuring SC-CO2. Herein, the rGO/sulfur composite cathode prepared on a lab scale showed an initial discharge capacity of 1024 mAh/g at 0.1C rate with capacity retention of 92.2% and coulombic efficiency of 99% even after 200 charge-discharge cycles. The developed cells showed excellent performance (929 mAh/g at 1 C rate) with an ultralow decay of 0.04% per cycle even after 200 charge-discharge cycles. Through this work, we believe that the synergistic effect of SC-CO2 technology and rGO as sulfur host will open up a promising future for the synthesis of efficient S/C composite cathodes with ultra-high cycling stability.}, keywords = {REDUCED GRAPHENE OXIDE; supercritical fluid; Li-S battery; Sulfur cathode; Carbon–sulfur composite; Polysulfide confinement}, year = {2022}, eissn = {2468-5194}, orcid-numbers = {SHIVA SHANKAR, LAKSHMI/0000-0003-0832-4387; Szabó, Tamás/0000-0001-8182-640X; Kózelné Székely, Edit/0000-0002-6935-0071; Kőrösi, Márton/0000-0002-1224-4788; Balázsi, Katalin/0000-0002-8929-9672; Czigány, Zsolt/0000-0001-6410-8801} } @article{MTMT:33051154, title = {Nanomechanical, Structural and Electrochemical Investigation of Amorphous and Crystalline MoO3 Thin-Film Cathodes in Rechargeable Li-Ion Batteries}, url = {https://m2.mtmt.hu/api/publication/33051154}, author = {Methani, Wissem and Pál, Edit and Lipcsei, Sándor and Ugi, Dávid and Pászti, Zoltán and Groma, István and Jenei, Péter and Dankházi, Zoltán and Kun, Róbert}, doi = {10.3390/batteries8080080}, journal-iso = {BATTERIES}, journal = {BATTERIES}, volume = {8}, unique-id = {33051154}, abstract = {In this work, a comprehensive investigation of amorphous and crystalline modification of identical electrode active material as a thin-film electrode for a future all-solid-state Li-ion battery application is presented and discussed. Using the proposed micro-battery system, we aim to unravel the effect of the crystallinity of the positive electrode material on the intrinsic durability of all-solid-state thin-film Li-ion batteries during prolonged electrochemical cycling. We demonstrate the preparation, structural-, nanomechanical and electrochemical characteristics of molybdenum (VI) oxide (MoO3) thin-film cathodes based on their different crystallinity. The nanomechanical properties of the electrode layers were determined using nanoindentation along with acoustic emission studies. Based on the electrochemical test results, as-prepared thin films that did not go under any heat treatment showed the best performance and stability throughout cycling around 50 μAh initial capacity when cycled at C/2. This suits well their nanomechanical properties, which showed the highest hardness but also the highest flexibility in comparison with the heat-treated layers with lower hardness, high brittleness, and numerous cracks upon mechanical loads. According to our results, we state that amorphous-type electrode materials are more durable against electro-chemo-mechanical-aging related battery performance loss in all-solid-state Li-ion batteries compared to their crystalline counterparts.}, year = {2022}, eissn = {2313-0105}, orcid-numbers = {Lipcsei, Sándor/0000-0003-2220-105X; Groma, István/0000-0002-6644-1365; Jenei, Péter/0000-0001-5187-9893; Dankházi, Zoltán/0000-0001-9545-2015} } @article{MTMT:32850797, title = {Electrocatalytic Properties of Mixed-Oxide-Containing Composite-Supported Platinum for Polymer Electrolyte Membrane (PEM) Fuel Cells}, url = {https://m2.mtmt.hu/api/publication/32850797}, author = {Ayyubov, Ilgar and Tálas, Emília and Salmanzade, Khirdakhanim and Kuncser, Andrei and Pászti, Zoltán and Neațu, Ștefan and Mirea, Anca G. and Florea, Mihaela and Tompos, András and Borbáth, Irina}, doi = {10.3390/ma15103671}, journal-iso = {MATERIALS}, journal = {MATERIALS}, volume = {15}, unique-id = {32850797}, year = {2022}, eissn = {1996-1944}, orcid-numbers = {Kuncser, Andrei/0000-0003-2841-5809; Neațu, Ștefan/0000-0002-2450-0291; Florea, Mihaela/0000-0002-6612-6090} } @article{MTMT:32786599, title = {Interspecies Comparisons of the Effects of Potential Antiviral 3-Amidinophenylalanine Derivatives on Cytochrome P450 1A2 Isoenzyme}, url = {https://m2.mtmt.hu/api/publication/32786599}, author = {Fedor, Z. and Szentkirályi-Tóth, A. and Nagy, G. and Szimrók, Z. and Varga, E. and Pászti, A. and Pászti, Zoltán and Jerzsele, Ákos and Pilgram, O. and Steinmetzer, T. and Mátis, Gábor and Neogrády, Zsuzsa and Pásztiné Gere, Erzsébet}, doi = {10.3390/vetsci9040156}, journal-iso = {VET SCI}, journal = {VETERINARY SCIENCES}, volume = {9}, unique-id = {32786599}, issn = {2306-7381}, abstract = {In vitro models of animals vulnerable to SARS-CoV-2 infection can support the characterization of effective antiviral drugs, such as synthetic inhibitors of the transmembrane protease serine 2 (TMPRSS2). Changes in cytochrome P450 (CYP) 1A2 activities in the presence of the potential TMPRSS2/matriptase inhibitors (MI) were measured using fluorometric and luminescent assays. Furthermore, the cytotoxicity of these inhibitors was evaluated using the MTS method. In addition, 60 min-long microsomal stability assays were performed using an UPLC-MS/MS procedure to elucidate depletion rates of the inhibitors. CYP1A2 was influenced significantly by MI-463 and MI-1900 in rat microsomes, by MI-432 and MI-482 in beagle microsomes, and by MI-432, MI-463, MI-482, and MI-1900 in cynomolgus monkey microsomes. The IC50 values in monkey microsomes were 1.30 ± 0.14 µM, 2.4 ± 1.4 µM, 0.21 ± 0.09 µM, and 1.1 ± 0.8 µM for inhibitors MI-432, MI-463, MI-482, and MI-1900, respectively. The depletion rates of the parent compounds were lower than 50%, independently of the investigated animal species. The host cell factor TMPRSS2 is of key importance for the cross-species spread of SARS-CoV-2. Studies of the in vitro biotransformation of TMPRSS2 inhibitors provide additional information for the development of new antiviral drugs. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.}, keywords = {HEPATOCYTES; CYP1A2; Beagle; SARS-CoV-2; 3-amidinophenylalanine; cynomolgus monkey microsome}, year = {2022} } @article{MTMT:32776748, title = {Photocatalytic performance of alkali metal doped graphitic carbon nitrides and Pd-alkali metal doped graphitic carbon nitride composites}, url = {https://m2.mtmt.hu/api/publication/32776748}, author = {Fronczak, Maciej and Tálas, Emília and Pászti, Zoltán and Szijjártó, Gábor and Mihály, Judith and Tompos, András and Baranowski, Piotr and Tiwari, Santosh Kr. and Bystrzejewski, Michał}, doi = {10.1016/j.diamond.2022.109006}, journal-iso = {DIAM RELAT MATER}, journal = {DIAMOND AND RELATED MATERIALS}, volume = {125}, unique-id = {32776748}, issn = {0925-9635}, year = {2022}, eissn = {1879-0062} }