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Kessler, J., Donzel-Gargand, O., Moldarev, D., Franzén, C., Primetzhofer, D., Jansson, U. & Lewin, E. (2025). Magnetron sputtering of titanium carbonitride nanocomposite coatings: Does the choice of carbon source affect film properties?. Surface & Coatings Technology, 498, Article ID 131830.
Open this publication in new window or tab >>Magnetron sputtering of titanium carbonitride nanocomposite coatings: Does the choice of carbon source affect film properties?
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2025 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 498, article id 131830Article in journal (Refereed) Published
Abstract [en]

We report on a study of titanium carbonitride coatings, with potential applications as protective coatings on bipolar plates in fuel cells. Two series of Ti-C-N coatings with a carbon concentration varying between 8 and 34 at.% were deposited by magnetron sputtering, using a graphite target or methane gas as carbon source. Characterisation with X-ray diffraction, ion beam analysis, Raman spectroscopy and electron microscopy shows that the coatings consist of a crystalline titanium carbonitride phase and an amorphous carbon tissue phase: nc-Ti(C,N)/a-C(:N). It was found that the mechanical and electrical properties are primarily dependent on the carbon content and not the choice of carbon source. An increase in C content leads to a decreasing crystallite size and an increasing amount of amorphous carbon. Thus, the phase content and microstructure and thereby the properties are controlled by the carbon content, making the nc-Ti(C,N)/a-C(:N) coatings highly tuneable. Depending on C content hardness of 11-38 GPa and resistivity of 150-623 mu ohm cm was observed. Additionally, the coatings were found to exhibit a contact resistance against silver that was 10 times lower than that of a stainless steel reference. This makes titanium carbonitride nanocomposite coatings promising candidates for the use on bipolar plates in fuel cells.

Place, publisher, year, edition, pages
Elsevier, 2025
Keywords
Fuel cells, Bipolar plates, Carbonitride, Magnetron sputtering, Nanocomposite, Ti-C-N
National Category
Materials Chemistry Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-551739 (URN)10.1016/j.surfcoat.2025.131830 (DOI)001422608600001 ()2-s2.0-85216624281 (Scopus ID)
Funder
Vinnova, 2022-03071Swedish Research Council, 2020-00207Swedish Research Council, 2019-00191
Available from: 2025-03-26 Created: 2025-03-26 Last updated: 2025-03-26Bibliographically approved
Osinger, B., Casillas-Trujillo, L., Lindblad, R., Alling, B., Olovsson, W., Abrikosov, I. A. & Lewin, E. (2024). Charge transfer effects in (HfNbTiVZr)C – shown by ab-initio calculations and X-ray photoelectron spectroscopy. Journal of The American Ceramic Society, 107(11), 7562-7576
Open this publication in new window or tab >>Charge transfer effects in (HfNbTiVZr)C – shown by ab-initio calculations and X-ray photoelectron spectroscopy
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2024 (English)In: Journal of The American Ceramic Society, ISSN 0002-7820, E-ISSN 1551-2916, Vol. 107, no 11, p. 7562-7576Article in journal (Refereed) Published
Abstract [en]

Considering charge transfer effects and the variability of the bonding between elements with different electronegativity opens up a deeper understanding of the electronic structure and as a result many of the properties in high entropy related materials. This study investigates the importance of the diverse bonding and chemical environments when discussing multicomponent carbide materials. A combination of ab initio calculations and X-ray photoelectron spectroscopy (XPS) was used to investigate the electronic structure of multicomponent thin films based on the (HfNbTiVZr)C system. The charge transfer was quantified theoretically using relaxed and non-relaxed multicomponent as well as binary carbide reference structures, employing a fixed sphere model. High-resolution XPS spectra from (HfNbTiVZr)C magnetron sputtered thin films displayed core level binding energy shifts and broadening effects as a result of the complex chemical environment. Charge transfer effects and a changed electronic structure in the multicomponent material, compared with the reference binary carbides, are observed both experimentally and in the DFT simulations. The observed effects loosely follow electronegativity considerations, leading to a deviation from an ideal solid solution structure assuming non-distinguishable chemically equivalent environments. 

Place, publisher, year, edition, pages
John Wiley & Sons, 2024
Keywords
DFT, Magnetron sputtering, Multicomponent carbide, X-ray Photoelectron spectroscopy, Charge transfer
National Category
Materials Chemistry
Research subject
Chemistry with specialization in Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-517270 (URN)10.1111/jace.20021 (DOI)001270668300001 ()2-s2.0-85198737654 (Scopus ID)
Available from: 2024-01-09 Created: 2024-01-09 Last updated: 2025-01-10Bibliographically approved
Fritze, S., Hahn, R., Aboulfadl, H., Johansson, F. O. .., Lindblad, R., Böör, K., . . . Thuvander, M. (2024). Elemental distribution and fracture properties of magnetron sputtered carbon supersaturated tungsten films. Surface & Coatings Technology, 477, Article ID 130326.
Open this publication in new window or tab >>Elemental distribution and fracture properties of magnetron sputtered carbon supersaturated tungsten films
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2024 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 477, article id 130326Article in journal (Refereed) Published
Abstract [en]

The combination of strength and toughness is a major driving force for alloy design of protective coatings, and nanocrystalline tungsten (W)-alloys have shown to be promising candidates for combining strength and toughness. Here we investigate the elemental distribution and the fracture toughness of carbon (C) alloyed W thin films prepared by non-reactive magnetron sputtering. W:C films with up to ~4 at.% C crystallize in a body-centered-cubic structure with a strong 〈hh0〉texture, and no additional carbide phases are observed in the diffraction pattern. Atom probe tomography and X-ray photoelectron spectroscopy confirmed the formation of such a supersaturated solid solution. The pure W film has a hardness ~13 GPa and the W:C films exhibit a peak hardness of ~24 GPa. In-situ micromechanical cantilever bending tests show that the fracture toughness decreases from ~4.5 MPa·m1/2 for the W film to ~3.1 MPa·m1/2 for W:C films. The results show that C can significantly enhance the hardness of W thin films while retaining a high fracture toughness.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
PVD, Fracture toughness, Atom probe tomography, XPS, Tungsten
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-521828 (URN)10.1016/j.surfcoat.2023.130326 (DOI)001149676000001 ()
Funder
Swedish Foundation for Strategic Research, RMA15-0048
Available from: 2024-01-29 Created: 2024-01-29 Last updated: 2024-02-15Bibliographically approved
Srinath, A., von Fieandt, K., Fritze, S., Nyholm, L., Lewin, E. & Lindblad, R. (2024). Near-surface analysis of magnetron sputtered AlCrNbYZrNx high entropy materials resolved by HAXPES. Applied Surface Science, 666, Article ID 160349.
Open this publication in new window or tab >>Near-surface analysis of magnetron sputtered AlCrNbYZrNx high entropy materials resolved by HAXPES
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2024 (English)In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 666, article id 160349Article in journal (Refereed) Published
Abstract [en]

Hard X-ray photoelectron spectroscopy (HAXPES) was used to perform a non-destructive depth profile of AlCrNbYZrNx (x = 0 to ∼50 at.%) thin films. The outermost native oxide of the pristine thin films contained the highest coordination oxides of every metal. Substoichiometric oxides or oxynitrides were found underneath. After exposure to 1.0 M HCl, increases in the most highly coordinated oxides of Cr, Nb, and Al in films with up to 37 at.% N were observed, suggesting that the low coordination oxides and oxynitrides in the subsurface had been further oxidised and were intermediary compounds in the passivation process. Al and Y oxides were lost to the HCl electrolyte, in agreement with their respective Pourbaix diagrams. The film with 49 at.% N showed little to no change in the data due to its high porosity which led to the oxide being detected at all probed depths. The metal core level spectra revealed a preferential order in which nitrogen bonded with the different metals. Nitrogen interacted first with Y, then Zr, then Al and Nb, and lastly Cr as the nitrogen content was increased.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Multicomponent alloys, Passivation, Corrosion, Metal nitrides, Synchrotron radiation
National Category
Surface- and Corrosion Engineering Materials Chemistry Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-466218 (URN)10.1016/j.apsusc.2024.160349 (DOI)001247335700001 ()
Funder
EU, Horizon 2020, 730872
Available from: 2022-01-25 Created: 2022-01-25 Last updated: 2025-02-09Bibliographically approved
Osinger, B., Donzel-Gargand, O., Fritze, S., Jansson, U. & Lewin, E. (2024). Structural and mechanical properties of magnetron sputtered (NbxMo1-x)C thin films. Vacuum, 224, Article ID 113146.
Open this publication in new window or tab >>Structural and mechanical properties of magnetron sputtered (NbxMo1-x)C thin films
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2024 (English)In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 224, article id 113146Article in journal (Refereed) Published
Abstract [en]

While transition metal carbides (TMCs) exhibit favourable mechanical properties, alloying according to the valence electron concentration (VEC) has the potential to further enhance the properties of these hard but inherently brittle materials. This study investigates the influence of alloying on the microstructure and mechanical properties of (NbxMo1-x)C carbide films, including binary references and ternary compositions with varying metal ratios (x between 0.35 and 0.53). Furthermore, the influence of various substrate materials is studied by comparing films deposited on Al2O3, MgO and SiO2. All films exhibit a NaCl-type carbide structure and X-ray photoelectron spectroscopy revealed the presence of small amounts of an additional amorphous carbon (a-C) phase. Hardness values around 20 ± 2 GPa were obtained for the films on Al2O3 and MgO, whereas a reduced hardness of 11 ± 1 GPa was observed for the films on SiO2 which is attributed to larger crystallite size and more polycrystalline structure. Overall no clear trend as a function of composition can be noted, indicating that microstructure effects dominate the mechanical properties in this study overshadowing the effect of varying the metal content.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Magnetron sputtering, Ceramic coating, Transition metal carbides, Mechanical properties
National Category
Materials Chemistry
Research subject
Chemistry with specialization in Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-517298 (URN)10.1016/j.vacuum.2024.113146 (DOI)001218592400001 ()
Funder
Swedish Research Council, 2018-04834Swedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2024-01-09 Created: 2024-01-09 Last updated: 2024-05-31Bibliographically approved
Jansson, A., Zendejas Medina, L., Lewin, E., Donzel-Gargand, O., Jansson, U. & Lautrup, L. (2024). Substrate orientation influence on nanotwinning in magnetron sputtered CoCrFeMnNi and Ni coatings. Materials & design, 246, Article ID 113343.
Open this publication in new window or tab >>Substrate orientation influence on nanotwinning in magnetron sputtered CoCrFeMnNi and Ni coatings
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2024 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 246, article id 113343Article in journal (Refereed) Published
Abstract [en]

This study reveals the influence of crystal orientation on formation of growth twins in magnetron-sputtered coatings. A comparison between materials with low and high stacking fault energy (SFE) was made: CoCrFeMnNi (25 mJ/m(2)) and Ni (125 mJ/m(2)). The coatings were grown on a polycrystalline 316L stainless-steel substrate with near-random crystal texture, providing a comprehensive selection of samples on a single substrate. Electron backscatter diffraction was used to identify the film orientation, followed by transmission electron microscopy of selected regions. The presence and density of twins depended on both the material and the growth orientation. For Ni, nanotwins were observed on < 5 % of the substrate grains, on growth directions closest to (1 1 1) . All other film orientations grew epitaxially with a cube-on-cube relationship. For CoCrFeMnNi, nanotwinning was observed on 50 % of the substrate grains, deviating < 35 degrees from (1 1 1) . In the nanotwinned regions, the twin spacing was 10-100 nm for Ni and 2-20 nm for CoCrFeMnNi. The presence of nanotwins increased hardness in both materials. The mechanism behind these differences is discussed, together with other parameters for controlling twin density. Our results show that control of the growth process can be used for nanotwin-engineering in magnetron-sputtered materials with low SFE.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
CoCrFeMnNi, HEA, Magnetron sputtering, Nanotwinning, 4D-STEM, HRTEM
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-541287 (URN)10.1016/j.matdes.2024.113343 (DOI)001331620300001 ()
Funder
Vinnova, 2016-05156Swedish Research Council, 2019-00207
Available from: 2024-10-30 Created: 2024-10-30 Last updated: 2024-10-30Bibliographically approved
Tunes, M. A., Fritze, S., Osinger, B., Willenshofer, P., Alvarado, A. M., Martinez, E., . . . El-Atwani, O. (2023). From high-entropy alloys to high-entropy ceramics: The radiation-resistant highly concentrated refractory carbide (CrNbTaTiW)C. Acta Materialia, 250, Article ID 118856.
Open this publication in new window or tab >>From high-entropy alloys to high-entropy ceramics: The radiation-resistant highly concentrated refractory carbide (CrNbTaTiW)C
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2023 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 250, article id 118856Article in journal (Refereed) Published
Abstract [en]

High-entropy materials represent the state-of-the-art on the alloy design strategy for future applications in extreme environments. Recent data indicates that high-entropy alloys (HEAs) exhibit outstanding radiation resistance in face of existing diluted alloy counterparts due to suppressed damage formation and evolution. An extension of the HEA concept is presented in this paper towards the synthesis and characterization of novel high-entropy ceramics as emergent materials for application in environments where energetic particle irradiation is a major concern. A novel carbide within the quinary refractory system CrNbTaTiW has been synthesized using magnetron-sputtering. The material exhibited nanocrystalline grains, single-phase crystal structure and C content around 50 at.%. Heavy-ion irradiation with in-situ Transmission Electron Microscopy was used to assess the irradiation response of the new high-entropy carbide (HEC) at 573 K and a comparison with the HEA within the system is made. No displacement damage effects appear within the microstructures of both HEA and HEC up to a dose of 10 displacements-per-atom. Surprisingly, the HEC has not amorphized under the investigated conditions. Xe was implanted in both materials and bubbles nucleated, but smaller sizes compared with conventional nuclear materials shedding light they are potential candidates for use in nuclear energy.

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
High-entropy ceramics, High-entropy alloys, Nanocrystalline materials, Radiation damage, Extreme environments
National Category
Materials Engineering
Identifiers
urn:nbn:se:uu:diva-499313 (URN)10.1016/j.actamat.2023.118856 (DOI)000958714700001 ()
Funder
EU, European Research Council, 757961Swedish Research Council, 2017-00646_9Swedish Research Council, 2019_00191Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2023-03-27 Created: 2023-03-27 Last updated: 2024-01-11Bibliographically approved
Greczynski, G., Haasch, R. T., Hellgren, N., Lewin, E. & Hultman, L. (2023). X-ray photoelectron spectroscopy of thin films. NATURE REVIEWS METHODS PRIMERS, 3(1), Article ID 40.
Open this publication in new window or tab >>X-ray photoelectron spectroscopy of thin films
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2023 (English)In: NATURE REVIEWS METHODS PRIMERS, ISSN 2662-8449, Vol. 3, no 1, article id 40Article in journal (Refereed) Published
Abstract [en]

X-ray photoelectron spectroscopy (XPS) is a popular analytical technique in materials science as it can assess the surface chemistry of a broad range of samples. This Primer concerns best practice in XPS analysis, aimed at both entry-level and advanced users, with a focus on thin film samples synthesized under vacuum conditions. The high surface to volume ratio of thin films means that factors such as substrate choice and air exposure time are important for the final result. Essential concepts are introduced, such as binding energy, photoelectric effect, spectral referencing and chemical shift, as well as practical aspects including surface sensitivity, probing depth, energy resolution, sample handling and sputter etching. Correct procedures for experimental planning, instrument set-up, sample preparation, data acquisition, results analysis and presentation are reviewed in connection with physical principles and common applications. Typical problems, including charging, spectral overlap, sputter damage and binding energy referencing, are discussed along with possible solutions or workarounds. Finally, a workflow is presented for arriving at high-quality results. X-ray photoelectron spectroscopy (XPS) can be used to investigate chemical bonding and elemental composition. This Primer discusses how XPS can be used to characterize thin films, including key considerations for sample preparation, experimental set-up and data analysis.

Place, publisher, year, edition, pages
Springer NatureSpringer Nature, 2023
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-505223 (URN)10.1038/s43586-023-00225-y (DOI)000995347100001 ()
Funder
Swedish Research Council, 2018-03957Swedish Energy Agency, 51201-1Knut and Alice Wallenberg Foundation, KAW2019.0290Vinnova, 2022-03071
Available from: 2023-06-27 Created: 2023-06-27 Last updated: 2024-12-03Bibliographically approved
Hanifpour, F., Canales, C. P., Fridriksson, E. G., Sveinbjörnsson, A., Tryggvason, T. K., Lewin, E., . . . Flosadóttir, H. D. (2022). Investigation into the mechanism of electrochemical nitrogen reduction reaction to ammonia using niobium oxynitride thin-film catalysts. Electrochimica Acta, 403, Article ID 139551.
Open this publication in new window or tab >>Investigation into the mechanism of electrochemical nitrogen reduction reaction to ammonia using niobium oxynitride thin-film catalysts
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2022 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 403, article id 139551Article in journal (Refereed) Published
Abstract [en]

Niobium oxynitride (NbOxNy) thin films with varying combined non-metal vs. metal stoichiometries ( x + y ) and N/O stoichiometric ratios (y/x) are investigated for their ability to catalyze the nitrogen re-duction reaction and ammonia synthesis at ambient conditions. Electrochemical impedance spectroscopy and ammonia measurements show stark differences both in nitrogen vs. argon media on each surface and on the surfaces in the series when the combined stoichiometry of N + O vs. Nb increases. Surface stability checks at fixed intervals during the experiments and surface characterization after the experiments us -ing X-ray diffraction reveal the least changes occurred to the surface with the highest N + O stoichiometry. Based on these observations, an ammonia synthesis mechanism is proposed. Isotope labeling experiments on the most promising surface of the series, however, show no sign of catalytically produced ammonia, possibly due to the lack of stability of the surface to endure through the ammonia production cycle. 

Place, publisher, year, edition, pages
ElsevierElsevier BV, 2022
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-470305 (URN)10.1016/j.electacta.2021.139551 (DOI)000784296000004 ()
Available from: 2022-03-22 Created: 2022-03-22 Last updated: 2024-01-15Bibliographically approved
Osinger, B., Mao, H., Fritze, S., Riekehr, L., Jansson, U. & Lewin, E. (2022). Investigation of the phase formation in magnetron sputtered hard multicomponent (HfNbTiVZr)C coatings. Materials & design, 221, Article ID 111002.
Open this publication in new window or tab >>Investigation of the phase formation in magnetron sputtered hard multicomponent (HfNbTiVZr)C coatings
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2022 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 221, article id 111002Article in journal (Refereed) Published
Abstract [en]

Multicomponent carbides have gained interest especially for ultra-high temperature applications, due to their ceramic hardness, good oxidation resistance and enhanced strength. In this study the phase forma-tion, stability and mechanical properties of (HfNbTiVZr)C multicomponent carbide coatings were inves-tigated. Phase stability was predicted by the CALPHAD (CALculation of PHAse Diagrams) methods. This revealed that the multicomponent solid solution phase is only stable at elevated temperatures, namely above 2400 degrees C. At lower temperatures a phase mixture was predicted, with a particular tendency for V to segregate. Magnetron sputtered thin films deposited at 300 degrees C exhibited a single NaCl-type multicom-ponent carbide phase, which attributes to the kinetic stabilisation of simple structures during thin film growth. Films deposited at 700 degrees C, or exposed to UHV annealing at 1000 degrees C, however, revealed the decom-position of the single-phase multicomponent carbide by partial elemental segregation and formation of additional phases. Thus, confirming the CALPHAD predictions. These results underscore the importance of explicitly considering temperature when discussing the stability of multicomponent carbide materials, as well as the applicability of CALPHAD methods for predicting phase formation and driving forces in these materials. The latter being crucial for designing materials, such as carbides, that are used in appli-cations at elevated temperatures.

Place, publisher, year, edition, pages
ElsevierElsevier BV, 2022
Keywords
High entropy ceramics, Multi -principal element carbide, Multicomponent carbide, Physical vapour deposition (PVD), CALPHAD
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-482676 (URN)10.1016/j.matdes.2022.111002 (DOI)000839257000004 ()
Funder
Swedish Research Council, 2018-04834Swedish Research CouncilSwedish Research Council, 2017-00646_9Swedish Foundation for Strategic Research, RIF14-0053
Available from: 2022-09-07 Created: 2022-09-07 Last updated: 2024-01-15Bibliographically approved
Projects
Anmälan om utnyttjande av återvändarbidrag för beviljade postdoktorsstipendier inom medicin eller natur- och teknikvetenskap [2013-00069_VR]; Uppsala UniversityAluminium carbonitride-based nanolaminates - a route to new materials [2022-03120_VR]; Uppsala University
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-8617-4834

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