@article{MTMT:34762097, title = {Effect of Non‐Thermal Sulfur Hexafluoride Cold Plasma Modification on Surface Properties of Polyoxymethylene}, url = {https://m2.mtmt.hu/api/publication/34762097}, author = {Chodkowski, Michał and Terpiłowski, Konrad and Románszki, Loránd and Klébert, Szilvia and Mohai, Miklós and Károly, Zoltán}, doi = {10.1002/cphc.202300709}, journal-iso = {CHEMPHYSCHEM}, journal = {CHEMPHYSCHEM: A EUROPEAN JOURNAL OF CHEMICAL PHYSICS AND PHYSICAL CHEMISTRY}, unique-id = {34762097}, issn = {1439-4235}, abstract = {X‐ray photoelectron spectroscopy was employed to reveal the differences in the chemical structure of the topmost layer after plasma modification. It was found out that changes in the surface properties of the polymer could be observed even after 20 seconds of treatment. The surface becomes hydrophobic or superhydrophobic, with the water contact angles up to 160 degrees. Morphological changes and increased roughness can be observed only in the nanoscale, whereas the structure seems to be unaffected in the microscale. As a result of plasma modification a permanent hydrophobic effect was obtained on the polyoxymethylene surface.}, year = {2024}, eissn = {1439-7641}, orcid-numbers = {Terpiłowski, Konrad/0000-0002-8078-3644; Klébert, Szilvia/0000-0002-3107-3371} } @article{MTMT:34448239, title = {Qualitative and quantitative chemometric modelling of nanostructured carbon samples based on infrared spectroscopy}, url = {https://m2.mtmt.hu/api/publication/34448239}, author = {Rácz, Anita and Nagyné László, Krisztina and Klébert, Szilvia}, doi = {10.1016/j.carbon.2023.118743}, journal-iso = {CARBON}, journal = {CARBON}, volume = {218}, unique-id = {34448239}, issn = {0008-6223}, year = {2024}, eissn = {1873-3891}, orcid-numbers = {Nagyné László, Krisztina/0000-0003-4499-3983; Klébert, Szilvia/0000-0002-3107-3371} } @article{MTMT:34110212, title = {Determination of melt flow index and polymer additives in polyethylene based on IR spectra and multivariate modeling}, url = {https://m2.mtmt.hu/api/publication/34110212}, author = {Rácz, Anita and Renkeczné Tátraaljai, Dóra and Klébert, Szilvia}, doi = {10.1016/j.mtchem.2023.101671}, journal-iso = {MATER TODAY CHEM}, journal = {MATERIALS TODAY CHEMISTRY}, volume = {33}, unique-id = {34110212}, issn = {2468-5194}, year = {2023}, eissn = {2468-5194}, orcid-numbers = {Klébert, Szilvia/0000-0002-3107-3371} } @article{MTMT:34106212, title = {The Influence of Reduced Graphene Oxide on the Texture and Chemistry of N,S-Doped Porous Carbon. Implications for Electrocatalytic and Energy Storage Applications}, url = {https://m2.mtmt.hu/api/publication/34106212}, author = {Samaniego Andrade, Samantha Kathiuska and SHIVA SHANKAR, LAKSHMI and Bakos, István and Klébert, Szilvia and Kun, Róbert and Mohai, Miklós and Nagy, Balázs and Nagyné László, Krisztina}, doi = {10.3390/nano13162364}, journal-iso = {NANOMATERIALS-BASEL}, journal = {NANOMATERIALS}, volume = {13}, unique-id = {34106212}, abstract = {In this work, we study the influence of reduced graphene oxide (rGO) on the morphology and chemistry of highly porous N,S-doped carbon cryogels. Simultaneously, we propose an easily upscalable route to prepare such carbons by adding graphene oxide (GO) in as-received suspended form to the aqueous solution of the ι-carrageenan and urea precursors. First, 1.25–5 wt% GO was incorporated into the dual-doped polymer matrix. The CO2, CO, and H2O emitted during the thermal treatments resulted in the multifaceted modification of the textural and chemical properties of the porous carbon. This facilitated the formation of micropores through self-activation and resulted in a substantial increase in the apparent surface area (up to 1780 m2/g) and pore volume (up to 1.72 cm3/g). However, adding 5 wt% GO led to overactivation. The incorporated rGO has an ordering effect on the carbon matrix. The evolving oxidative species influence the surface chemistry in a complex way, but sufficient N and S atoms (ca. 4 and >1 at%, respectively) were preserved in addition to the large number of developing defects. Despite the complexity of the textural and chemical changes, rGO increased the electrical conductivity monotonically. In alkaline oxygen reduction reaction (ORR) tests, the sample with 1.25 wt% GO exhibited a 4e− mechanism and reasonable stability, but a higher rGO content gradually compromised the performance of the electrodes. The sample containing 5 wt% GO was the most sensitive under oxidative conditions, but after stabilization it exhibited the highest gravimetric capacitance. In Li-ion battery tests, the coulombic efficiency of all the samples was consistently above 98%, indicating the high potential of these carbons for efficient Li-ion insertion and reinsertion during the charge–discharge process, thereby providing a promising alternative for graphite-based anodes. The cell from the 1.25 wt% GO sample showed an initial discharge capacity of 313 mAh/g, 95.1% capacity retention, and 99.3% coulombic efficiency after 50 charge–discharge cycles.}, year = {2023}, eissn = {2079-4991}, orcid-numbers = {SHIVA SHANKAR, LAKSHMI/0000-0003-0832-4387; Klébert, Szilvia/0000-0002-3107-3371; Nagyné László, Krisztina/0000-0003-4499-3983} } @article{MTMT:34065321, title = {Effect of Carbon Nanoparticles on the Porous Texture of ι-Carrageenan-Based N-Doped Nanostructured Porous Carbons and Implications for Gas Phase Applications}, url = {https://m2.mtmt.hu/api/publication/34065321}, author = {Samaniego Andrade, Samantha Kathiuska and Kállay-Menyhárd, Alfréd and Klébert, Szilvia and Mohai, Miklós and Nagy, Balázs and Nagyné László, Krisztina}, doi = {10.3390/c9030068}, journal-iso = {C-J CARBON RES}, journal = {C: JOURNAL OF CARBON RESEARCH}, volume = {9}, unique-id = {34065321}, abstract = {S and N double-doped high surface area biomass-derived carbons were obtained from marine biomass-derived ι-carrageenan. Adding carbon nanoparticles (CNPs), namely graphene oxide (GO) or carbon nanotubes (CNTs), in the early stage of the synthesis leads to a modified porous texture and surface chemistry. The porous textures were characterized by N2 (−196.15 °C) and CO2 (0 °C) isotherms. The best GO- and CNT-added carbons had an apparent surface area of 1780 m2/g and 1170 m2/g, respectively, compared to 1070 m2/g for the CNP-free matrix. Analysis of the Raman spectra revealed that CNT was more efficient in introducing new defects than GO. Based on XPS, the carbon samples contain 2–4.5 at% nitrogen and 1.1 at% sulfur. The Dubinin–Radushkevich (DR) and Henry models were used to assess the strength of the interactions between various gases and the surface. The N2/H2 and CO2/CH4 selectivities were estimated with ideal adsorbed solution theory (IAST). While the CNPs, particularly GO, had a remarkable influence on the porous texture and affected the surface chemistry, their influence on the separation selectivity of these gases was more modest.}, year = {2023}, eissn = {2311-5629}, orcid-numbers = {Klébert, Szilvia/0000-0002-3107-3371; Nagyné László, Krisztina/0000-0003-4499-3983} } @{MTMT:33620312, title = {Eljárás mikroméretű nikkel-cink-ferrit (NixZn1-xFe2O4, 0 < x < 1) előállítására}, url = {https://m2.mtmt.hu/api/publication/33620312}, author = {Bódis, Eszter and Fazekas, Péter and Károly, Zoltán and Keszler, Anna Mária and Klébert, Szilvia and Kótai, László and Szépvölgyi, János}, unique-id = {33620312}, abstract = {Jelen találmány tárgya eljárás nikkel-cink-ferrit (NixZn1-xFe2O4, 0