1. Structure and properties of samarium-doped lanthanum hafnates annealed at the temperatures of 800 and 900 ◦COlena Lavrynenko, Marjeta Maček, Damjan Vengust, Oksana A. Korniienko, Alisa Atamanchuk, Andrey Ragulya, 2026, izvirni znanstveni članek Ključne besede: lanthanum hafnates, diffuse reflectance spectroscopy, ordered pyrochlore, optical properties
Objavljeno v DiRROS: 01.09.2026; Ogledov: 100; Prenosov: 55
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2. Manganese oxide and oxide-hydroxide composites with halloysite nanotubes as cationic & anionic dye degradation photocatalystsIryna Kovinchuk, Georgii V. Sokolsky, Giuseppe Lazzara, Marjeta Maček, O. Sanginova, Matjaž Spreitzer, Andrey Ragulya, 2026, izvirni znanstveni članek Ključne besede: manganese oxides, halloysite nanotubes, dye degradation
Objavljeno v DiRROS: 01.09.2026; Ogledov: 96; Prenosov: 58
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3. Dual-metal co-catalyst integrated graphitic carbon nitride for photocatalytic hydrogen evolution reactionSuraj Gupta, Samar Batool, Marjeta Maček, Nina Daneu, Joyal Johny, Matjaž Spreitzer, Alexey Cherevan, 2027, izvirni znanstveni članek Povzetek: Graphitic carbon nitride (g-C3N4) nanosheets are extensively used in photocatalytic applications but are often decorated with noble-metal co-catalysts to yield relevant efficiencies. Herein, we report a dual-metal co-catalyst system comprising cobalt and molybdenum (CoMo) nanoclusters uniformly integrated into heptazine g-C3N4 nanosheets for enhanced visible-light-driven hydrogen evolution reaction (HER). The intimate contact between metals as well as with gC3N4 layer was verified through X-ray absorption and X-ray photoelectron spectroscopies. Mechanistic insights obtained through a combination of experimental and computational studies suggest that Co acts as primary catalytic center, while Mo plays a preliminary role in facilitating surface hydrogen coverage, collectively accelerating the redox rates and achieving 10 times higher performance compared to bare gC3N4. Post-HER analysis reveals disintegration of co-catalyst into Co single-atoms, which then takes the leading role in sustaining the HER. The role of co-catalyst was mainly limited to the surface, acting as electron trap, reducing charge recombination and as a HER catalytic center. The composite exhibits excellent photostability over 13 h of ON/OFF illumination cycles, highlighting its potential for intermittent operations under practical conditions. This study presents a co-catalyst design strategy leveraging dual-metal synergy as a non-noble, scalable alternative to conventional noble-metal-based HER co-catalysts for solar fuel generation.
Ključne besede: hydrogen evolution reaction, nanosheets
Objavljeno v DiRROS: 30.06.2026; Ogledov: 251; Prenosov: 290
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4. Strain-gradient and curvature-induced changes in domain morphology of ▫$BaTiO_3$▫ nanorods : Experimental and theoretical studiesOlha A. Kovalenko, Eugene A. Eliseev, Yuriy O. Zagorodniy, Srečo D. Škapin, Marjeta Maček, Lesya D. Demchenko, Valentin V. Laguta, Zdravko Kutnjak, Dean R. Evans, Anna N. Morozovska, 2026, izvirni znanstveni članek Povzetek: We investigate the impact of OH− ions incorporation on the lattice strain and spontaneous polarization of BaTiO3 nanorods synthesized under different conditions. It was confirmed that the lattice strain depends directly on Ba supersaturation, with higher supersaturation leading to an increase in the lattice strain. However, it was shown that crystal growth and observed lattice distortion are not primarily influenced by external strain; rather, OH− ions incorporation plays a key role in generating internal chemical strains and driving these processes. By using the less reactive TiO2 precursor instead of TiOCl2 and controlling Ba supersaturation, the slower nucleation rate enables more effective regulation of OH− ions incorporation and crystal growth. This in turn effects both particle size and lattice distortion, leading to �/� ratio of 1.013–1.014. The incorporation of OH− ions induces lattice elongation along the � axis, contributing to anisotropic growth, increasing of the rod diameter and their growth-induced bending. However, the possibility of the curvature-induced changes in domain morphology of BaTiO3 nanorods remains almost unexplored. To study the possibility, we perform analytical calculations and finite element modeling, which provide insights into the curvature-induced changes in the strain-gradient, polarization distribution, and domain morphology in BaTiO3 nanorods. Theoretical results reveal the appearance of the domain stripes in BaTiO3 nanorod when the curvature exceeds a critical angle. The physical origin of the domain stripes emergence is the tendency to minimize the elastic energy of the nanorod by the domain splitting. These findings suggest that BaTiO3 nanorods, with curvature-controllable amount of domain stripes, could serve as flexible race-track memory elements for flexotronics and domain-wall electronics. Overall, this work enhances the understanding of how the shape anisotropy, lattice strains, and strain gradients influence the domain morphology of ferroelectric nanorods, offering a pathway for tuning properties of the nanorods for advanced applications in nanoelectronics.
Ključne besede: nanorods, lattice strain, nanoelectronics, domain morphology
Objavljeno v DiRROS: 30.04.2026; Ogledov: 354; Prenosov: 340
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5. Steering the ▫$Bi_4Ti_3O_{12}-to-SrTiO_3$▫ hydrothermal transformation for controlling the functionality of two-dimensional (2D) ▫$SrTiO_3$▫ nanoplatelets for photocatalytic ▫$H_2$▫ evolutionMarjeta Maček, Nina Daneu, Kamal Khaja Mohaideen, Blaž Likozar, Alja Čontala, Matjaž Spreitzer, Jeffrey C. S. Wu, Suraj Gupta, 2026, izvirni znanstveni članek Ključne besede: hydrogen production, nanoplatelets, hydrothermal transformation
Objavljeno v DiRROS: 08.01.2026; Ogledov: 803; Prenosov: 542
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7. The role of carbon presence on the strontium hexaferrite phase decomposition during pressureless spark plasma sintering (pSPS)Aleksander Učakar, Andraž Kocjan, Blaž Belec, Janez Košir, Tanja Kallio, Marjeta Maček, Bor Arah, Petra Jenuš, 2025, izvirni znanstveni članek Povzetek: The phase composition and microstructure of Sr-hexaferrite (SFO) ceramics govern the hard magnetic properties. Here, pressureless spark plasma sintering (pSPS) technique was employed for the rapid consolidation (500°C/min) of SFO in a radiating graphite crucible under vacuum and, thus, reductive conditions. A numerical model depicting the temperature profile within the heating crucible was constructed to understand the temperature evolution within the samples. The combination pSPS sintering environment (graphite heating crucible under vacuum) promoted phase decomposition to Sr-enriched and depleted phases of various morphological variations, leading to reduction of hard magnetic properties. Notably, certain newly formed phases exhibited lower melting points, inducing a shift in the sintering mechanism from solid-state sintering to a partial liquid-phase sintering mechanism.
Ključne besede: pressureless spark plasma sintering, electronic ceramics, numerical simulations
Objavljeno v DiRROS: 03.09.2025; Ogledov: 1035; Prenosov: 918
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8. Synergistic enhancement of photocatalytic CO [sub] 2 reduction by plasmonic Au nanoparticles on TiO [sub] 2 decorated N-graphene heterostructure catalyst for high selectivity methane productionKamal Khaja Mohaideen, Rekha Narayan, Narendraraj Chandran, Stefan Popović, Mohammed Azeezulla Nazrulla, Janez Kovač, Nika Vrtovec, Marjan Bele, Nejc Hodnik, Marjeta Maček, Blaž Likozar, 2022, izvirni znanstveni članek Objavljeno v DiRROS: 09.03.2022; Ogledov: 5996; Prenosov: 1788
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