2331. Effect of the Morphology of the High-Surface-Area Support on the Performance of the Oxygen-Evolution Reaction for Iridium NanoparticlesLeonard Moriau, Marjan Bele, Živa Marinko, Francisco Ruiz-Zepeda, Gorazd Koderman, Martin Šala, Angelija Kjara Šurca, Janez Kovač, Iztok Arčon, Primož Jovanovič, Nejc Hodnik, Luka Suhadolnik, 2021, original scientific article Abstract: The development of affordable, low-iridium-loading,
scalable, active, and stable catalysts for the oxygen-evolution
reaction (OER) is a requirement for the commercialization of
proton-exchange membrane water electrolyzers (PEMWEs).
However, the synthesis of high-performance OER catalysts with
minimal use of the rare and expensive element Ir is very challenging
and requires the identification of electrically conductive and stable
high-surface-area support materials. We developed a synthesis
procedure for the production of large quantities of a nanocomposite
powder containing titanium oxynitride (TiONx) and Ir.
The catalysts were synthesized with an anodic oxidation process
followed by detachment, milling, thermal treatment, and the
deposition of Ir nanoparticles. The anodization time was varied to grow three different types of nanotubular structures exhibiting different lengths and wall thicknesses and thus a variety of properties. A comparison of milled samples with different degrees of nanotubular clustering and morphology retention, but with identical
chemical compositions and Ir nanoparticle size distributions and dispersions, revealed that the nanotubular support morphology is
the determining factor governing the catalyst’s OER activity and stability. Our study is supported by various state-of-the-art
materials’ characterization techniques, like X-ray photoelectron spectroscopy, scanning and transmission electron microscopies, Xray powder diffraction and absorption spectroscopy, and electrochemical cyclic voltammetry. Anodic oxidation proved to be a very suitable way to produce high-surface-area powder-type catalysts as the produced material greatly outperformed the IrO2 benchmarks
as well as the Ir-supported samples on morphologically different TiONx from previous studies. The highest activity was achieved for the sample prepared with 3 h of anodization, which had the most appropriate morphology for the effective removal of oxygen
bubbles.
Keywords: electrocatalysis, oxygen-evolution reaction, TiONx-Ir powder catalyst, iridium nanoparticles, anodic oxidation, morphology−activity correlation
Published in RUNG: 04.01.2021; Views: 2628; Downloads: 0
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2332. Hidden black carbon air pollution in hilly rural areas - a case study of Dinaric depressionKristina Glojek, Asta Gregorič, Griša Močnik, Andrea Cuesta-Mosquera, A. Wiedensohler, Luka Drinovec, Matej Ogrin, 2020, original scientific article Abstract: Air pollution is not an exclusively urban problem as wood burning is a widespread practice in rural areas. As we lack information on the air quality situation in rural mountainous regions, our aim is to examine equivalent black carbon (eBC) pollution in a typical rural karst area in the settlement of Loški Potok (Slovenia). eBC mass concentrations were measured by Aethalometer (AE-33) at two sites in Retje karst depression. The rural village station was located at the bottom of the karst depression whereas the rural background station was positioned at the top of the hill. We showthe diurnal variation of equivalent black carbon mass concentrations for different seasons. In the populated karst depression, the major source of eBC pollution are households using wood as a heating fuel reaching the highest mass concentrations in winter. Diurnal pattern of eBC from biomass burning and traffic differ due to different source activity and it is influenced by typical formation of a cold air pool from late afternoon until late morning, restricting the dispersion of local emissions. The large difference in mass concentrations between the lowest part of the village (rural station) and the top of the hill (rural background station) indicates that in a vertically stratified and stable atmosphere local sources of black carbon have a major impact onair quality conditions in the area studied. Since in Alpine and Dinaric regions there are many similar inhabited areas, we can expect similar air quality conditions also in other rural hilly areas with limited self-cleaning air capacity.
Keywords: air pollution, black carbon, hidden geographies, diurnal variation, biomass burning, relief depressions, Loški Potok, Slovenia
Published in RUNG: 04.01.2021; Views: 2421; Downloads: 0
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2333. DNA metabarcoding of fungal diversity in air and snow of Livingston Island, South Shetland Islands, AntarcticaLuiz Henrique Rosa, Otávio Henrique Bezerra Pinto, Tina Šantl Temkiv, Peter Convey, Micheline Carvalho‑Silva, Carlos Augusto Rosa, Paulo E. A. S. Câmara, 2020, original scientific article Keywords: airborne fungi, metabarcoding, Antarctica
Published in RUNG: 04.01.2021; Views: 2277; Downloads: 81
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2334. Immersion freezing of ice nucleating active protein complexesSusan Hartmann, Stefanie Augustin, Tina Clauss, Heike Wex, Tina Šantl Temkiv, Jens Voigtländer, Dennis Niedermeier, Frank Stratmann, 2013, original scientific article Keywords: Ice nucleation, INP, ice-nucleating proteins, INA bacteria
Published in RUNG: 04.01.2021; Views: 2455; Downloads: 79
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2335. Remote sensing of life: polarimetric signatures of photosynthetic pigments as sensitive biomarkersSvetlana V. Berdyugina, Jeff R. Kuhn, David M. Harrington, Tina Šantl Temkiv, E. John Messersmith, 2016, original scientific article Keywords: biopigments, biosignatures, Earth-like planets, exoplanets, photosynthesis, remote sensing of life, spectropolarimetry
Published in RUNG: 04.01.2021; Views: 2370; Downloads: 0
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2337. Bioaerosol field measurements: Challenges and perspectives in outdoor studiesTina Šantl Temkiv, Branko Sikoparija, Teruya Maki, Federico Carotenuto, Pierre Amato, Maosheng Yao, Cindy E. Morris, Russ Schnell, Ruprecht Jaenicke, Christopher Pöhlker, Paul J. DeMott, Thomas C. J. Hill, J. Alex Huffman, 2020, review article Keywords: Bioaerosols, bioaerosol sampling, bioaerosol detection
Published in RUNG: 04.01.2021; Views: 2371; Downloads: 0
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2338. Biogenic Sources of Ice Nucleating Particles at the High Arctic Site Villum Research StationTina Šantl Temkiv, Robert Lange, David Beddows, Urška Rauter, Stephanie Pilgaard, Manuel Dall’Osto, Nina Gunde-Cimerman, Andreas Massling, Heike Wex, 2019, original scientific article Keywords: Arctic atmosphere, Arctic climate, biogenic ice nucleating particles, airborne bacteria, bioaerosols, ice nucleating particles
Published in RUNG: 04.01.2021; Views: 2614; Downloads: 0
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2339. Effect of Aerosolization and Drying on the Viability of Pseudomonas syringae CellsMalin Alsved, Stine Holm, Sigurd Christiansen, Mads Smidt, Meilee Ling, Thomas Boesen, Kai Finster, Merete Bilde, Jakob Löndahl, Tina Šantl Temkiv, 2018, original scientific article Keywords: bioaerosols, aerosolization, Pseudomonas syringae, drying, bubble bursting, ice nucleation activity
Published in RUNG: 04.01.2021; Views: 2224; Downloads: 62
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