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Sandström, R., Gracia-Espino, E., Annamalai, A., Persson, P., Persson, I., Ekspong, J., . . . Wågberg, T. (2020). Microwave-Induced Structural Ordering of Resilient Nanostructured L10-FePt Catalysts for Oxygen Reduction Reaction. ACS Applied Energy Materials, 3(10), 9785-9791
Öppna denna publikation i ny flik eller fönster >>Microwave-Induced Structural Ordering of Resilient Nanostructured L10-FePt Catalysts for Oxygen Reduction Reaction
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2020 (Engelska)Ingår i: ACS Applied Energy Materials, E-ISSN 2574-0962, Vol. 3, nr 10, s. 9785-9791Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We show how structurally ordered L10 face-centered tetragonal (fct) FePt nanoparticles are produced by a solid-state microwave-assisted synthesis method. The structural phase as well as the incorporated Fe into the nanoparticles is confirmed by X-ray diffraction and high resolution high-angle annular dark field scanning transmission electron microscopy experiments. The prepared particles exhibit a remarkable resilience toward crystallite growth at high temperatures. Directly correlated to the L10 phase, the best oxygen reduction reaction (ORR) characteristics are achieved for particles with a 1:1 Fe:Pt atomic ratio and an average size of ~2.9 nm where Pt-specific evaluation provided a high mass and specific activity of ~570 A/gPt and ~600 μA/cm2Pt respectively. Our results demonstrate that well-structured catalysts possessing activities vastly exceeding Pt/C (~210 A/gPt & ~250 μA/cm2Pt), can be synthesized through a fast and highly eco-friendly method. We note that the achieved mass activity represent a significant leap toward the theoretical maximum for fully ordered FePt nanoparticles.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2020
Nyckelord
Proton exchange membrane fuel cell, platinum iron, Oxygen reduction reaction, microwave synthesis, L1(0) phase, FePt-nanoparticles, electrocatalysts, structural ordering, electron microscopy
Nationell ämneskategori
Nanoteknik Annan materialteknik Den kondenserade materiens fysik
Forskningsämne
materialvetenskap; nanomaterial; nanopartiklar; fasta tillståndets fysik
Identifikatorer
urn:nbn:se:umu:diva-158495 (URN)10.1021/acsaem.0c01368 (DOI)000586710300036 ()2-s2.0-85096581760 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2017-04862Energimyndigheten, 45419-1Interreg NordÅForsk (Ångpanneföreningens Forskningsstiftelse), 15-483Vetenskapsrådet, 2016‐04412Stiftelsen för strategisk forskning (SSF), RIF 14‐0074Vetenskapsrådet, 2018-03937Olle Engkvists stiftelse, 186-0637
Anmärkning

Originally included in thesis in manuscript form  

Tillgänglig från: 2019-04-29 Skapad: 2019-04-29 Senast uppdaterad: 2023-03-24Bibliografiskt granskad
Sandström, R., Annamalai, A., Boulanger, N., Ekspong, J., Talyzin, A. V., Mühlbacher, I. & Wågberg, T. (2019). Evaluation of Fluorine and Sulfonic Acid Co-functionalized Graphene Oxide Membranes in Hydrogen Proton Exchange Membrane Fuel Cell Conditions. Sustainable Energy & Fuels, 3(7), 1790-1798
Öppna denna publikation i ny flik eller fönster >>Evaluation of Fluorine and Sulfonic Acid Co-functionalized Graphene Oxide Membranes in Hydrogen Proton Exchange Membrane Fuel Cell Conditions
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2019 (Engelska)Ingår i: Sustainable Energy & Fuels, E-ISSN 2398-4902, Vol. 3, nr 7, s. 1790-1798Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The use of graphene oxide (GO) based membranes consisting of self-assembled flakes with a lamellar structure represents an intriguing strategy to spatially separate reactants while facilitating proton transport in proton exchange membranes (PEM). Here we chemically modify GO to evaluate the role of fluorine and sulfonic acid groups on the performance of H2/O2 based PEM fuel cells. Mild fluorination is achieved by the presence of hydrogen fluoride during oxidation and subsequent sulfonation resulted in fluorine and SO3- co-functionalized GO. Membrane electrode assembly performance in low temperature and moderate humidity conditions suggested that both functional groups contribute to reduced H2 crossover compared to appropriate reference membranes. Moreover, fluorine groups promoted an enhanced hydrolytic stability while contributing to prevent structural degradation after constant potential experiments whereas sulfonic acid demonstrated a stabilizing effect by preserving proton conductivity.

Ort, förlag, år, upplaga, sidor
Royal Society of Medicine Press, 2019
Nyckelord
Proton exchange membrane, Fuel Cell, Graphene oxide, Hydrogen, Fluorine, Sulfonic acid
Nationell ämneskategori
Nanoteknik Annan kemiteknik Annan materialteknik Energisystem Den kondenserade materiens fysik
Forskningsämne
nanomaterial
Identifikatorer
urn:nbn:se:umu:diva-158496 (URN)10.1039/C9SE00126C (DOI)000472980200014 ()2-s2.0-85068152037 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2017-04862Energimyndigheten, 45419-1ÅForsk (Ångpanneföreningens Forskningsstiftelse), 15-483Interreg Nord
Anmärkning

Originally included in thesis in manuscript form

Tillgänglig från: 2019-04-29 Skapad: 2019-04-29 Senast uppdaterad: 2023-03-24Bibliografiskt granskad
Sandström, R. (2019). Innovations in nanomaterials for proton exchange membrane fuel cells. (Doctoral dissertation). Umeå: Umeå University
Öppna denna publikation i ny flik eller fönster >>Innovations in nanomaterials for proton exchange membrane fuel cells
2019 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Alternativ titel[sv]
Utveckling av nanomaterial för polymerelektrolytbränsleceller
Abstract [en]

Hydrogen technologies are rapidly receiving increased attention as it offers a renewable energy alternative to the current petroleum-based fuel infrastructure, considering that continued large-scale use of such fossil fuels will lead to disastrous impacts on our environment. The proton exchange membrane fuel cell should play a significant role in a hydrogen economy since it enables convenient and direct conversion of hydrogen into electricity, thus allowing the use of hydrogen in applications particularly suited for the transportation industry. To fully realize this, multiple engineering challenges as well as development of advanced nanomaterials must however be addressed.

In this thesis, we present discoveries of new innovative nanomaterials for proton exchange membrane fuel cells by targeting the entire membrane electrode assembly. Conceptually, we first propose new fabrication techniques of gas diffusion electrodes based on helical carbon nanofibers, where an enhanced three-phase boundary was noted in particular for hierarchical structures. The cathode catalyst, responsible for facilitating the sluggish oxygen reduction reaction, was further improved by the synthesis of platinum-based nanoparticles with an incorporated secondary metal (iron, yttrium and cobalt). Here, both solvothermal and high-temperature microwave syntheses were employed. Catalytic activities were improved compared to pure platinum and could be attributed to favorably shifted oxygen adsorption energies as a result of successful incorporation of the non-precious metal. As best exemplified by platinum-iron nanoparticles, the oxygen reduction reaction was highly sensitive to both metal composition and the type of crystal structure. Finally, a proton exchange membrane based on fluorine and sulfonic acid functionalized graphene oxide was prepared and tested in hydrogen fuel cell conditions, showing improvements such as lowered hydrogen permeation and better structural stability. Consequently, we have demonstrated that there is room for improvement of multiple components, suggesting that more powerful fuel cells can likely be anticipated in the future.

Ort, förlag, år, upplaga, sidor
Umeå: Umeå University, 2019. s. 88
Nyckelord
Fuel Cells, Membrane Electrode Assembly, Oxygen Reduction Reaction, Platinum alloy catalyst, Nanoparticles, Gas Diffusion Electrode, Proton Exchange Membrane
Nationell ämneskategori
Energisystem Nanoteknik Annan materialteknik Annan kemiteknik Den kondenserade materiens fysik
Forskningsämne
materialvetenskap; fasta tillståndets fysik
Identifikatorer
urn:nbn:se:umu:diva-158501 (URN)978-91-7855-044-9 (ISBN)
Disputation
2019-05-28, N460, Naturvetarhuset, Umeå, 10:15 (Engelska)
Opponent
Handledare
Tillgänglig från: 2019-05-07 Skapad: 2019-04-29 Senast uppdaterad: 2019-05-06Bibliografiskt granskad
Sandström, R., Ekspong, J., Gracia-Espino, E. & Wågberg, T. (2019). Oxidatively Induced Exposure of Active Surface Area during Microwave Assisted Formation of Pt3Co Nanoparticles for Oxygen Reduction Reaction. RSC Advances, 9(31), 17979-17987
Öppna denna publikation i ny flik eller fönster >>Oxidatively Induced Exposure of Active Surface Area during Microwave Assisted Formation of Pt3Co Nanoparticles for Oxygen Reduction Reaction
2019 (Engelska)Ingår i: RSC Advances, E-ISSN 2046-2069, Vol. 9, nr 31, s. 17979-17987Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The oxygen reduction reaction (ORR), the rate-limiting reaction in proton exchange membrane fuel cells, can efficiently be facilitated by properly manufactured platinum catalysts alloyed with late 3d transition metals. Herein we synthesize a platinum:cobalt nanoparticulate catalyst with a 3:1 atomic ratio by reduction of a dry organometallic precursor blend within a commercial household microwave oven. The formed nanoparticles are simultaneously anchored to a carbon black support that enables large Pt surface area. Two separate microwave treatment steps were employed, where step one constitutes a fast oxidative treatment for revealing active surface area while a reductive secondary annealing treatment promotes a Pt rich surface. The resulting Pt3Co/C catalyst (~3.4 nm) demonstrate an enhanced ORR activity directly attributed to incorporated Co with a specific and mass activity of 704 μA cm-2Pt and 352 A g-1Pt corresponding to an increase by 279 % and 66 % respectively compared to a commercial Pt/C (~1.8 nm) catalyst measured under identical conditions. The method´s simplicity, scalability and novelty is expected to further assist in Pt-Co development and bring the catalyst one step closer toward commercialization and utility in fuel cells.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2019
Nyckelord
Proton exchange membrane fuel cell, platinum cobalt, Oxygen reduction reaction, Microwave synthesis
Nationell ämneskategori
Nanoteknik Annan materialteknik Den kondenserade materiens fysik
Forskningsämne
nanomaterial; nanopartiklar; materialvetenskap
Identifikatorer
urn:nbn:se:umu:diva-158492 (URN)10.1039/c9ra02095k (DOI)000471914300054 ()2-s2.0-85067473239 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2017-04862ÅForsk (Ångpanneföreningens Forskningsstiftelse), 15-483Energimyndigheten, 45419-1Vetenskapsrådet, 2018-03937Olle Engkvists stiftelse, 186-0637
Anmärkning

Originally included in thesis in manuscript form 

Tillgänglig från: 2019-04-29 Skapad: 2019-04-29 Senast uppdaterad: 2023-03-24Bibliografiskt granskad
Sandström, R., Hu, G. & Wågberg, T. (2018). Compositional Evaluation of Coreduced Fe-Pt Metal Acetylacetonates as PEM Fuel Cell Cathode Catalyst. ACS Applied Energy Materials, 1(12), 7106-7115
Öppna denna publikation i ny flik eller fönster >>Compositional Evaluation of Coreduced Fe-Pt Metal Acetylacetonates as PEM Fuel Cell Cathode Catalyst
2018 (Engelska)Ingår i: ACS Applied Energy Materials, E-ISSN 2574-0962, Vol. 1, nr 12, s. 7106-7115Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Platinum iron nanoparticles were produced by solvothermal coreduction of organic Fe and Pt precursor compounds and supported on conventional Vulcan XC 72. Evaluation of oxygen reduction performance reveals a highly active surface with up to 5 times the specific activity of commercial Pt Vulcan measured in O-2-saturated 0.1 M HClO4. A particle size of 5.5 nm for the best performing sample, produced from an initial metal ratio of 1:1, provided 28% higher mass activity than the commercial reference. Membrane electrode assemblies, optimized for both H-2/O-2 and direct formic acid fuel cells, were produced, and the PEM fuel cell cathodic performance displayed results with similar enhancements as its ex situ measured mass activity, although a delamination of the catalyst layer from the membrane could be observed even when employing a hot-pressing procedure during MEA fabrication. Physical characterizations including X-ray photoelectron spectroscopy and in situ X-ray diffraction reveal oxidized states of Fe incorporated into the disordered face-centered cubic Pt nanoparticles, supported by composition-dependent morphological changes as observed by transmission electron microscopy. The provided insight into fuel cell performance as well as CO-oxidation attributes are expected to assist in selecting suitable applications and operating conditions for such FePt type nanoparticles.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2018
Nyckelord
platinum iron nanoparticles, proton exchange membrane fuel cell, oxygen reduction reaction, solvothermal coreduction, membrane electrode assembly, hydrogen energy
Nationell ämneskategori
Materialkemi Oorganisk kemi Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:umu:diva-156900 (URN)10.1021/acsaem.8b01536 (DOI)000458706800053 ()2-s2.0-85064760991 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2017-04862Energimyndigheten, 45419-1
Tillgänglig från: 2019-03-09 Skapad: 2019-03-09 Senast uppdaterad: 2023-03-24Bibliografiskt granskad
Annamalai, A., Sandström, R., Gracia-Espino, E., Boulanger, N., Boily, J.-F., Muehlbacher, I. & Wågberg, T. (2018). Double donor Sb5+doped hematite (Fe3+) photoanodes for surface-enhanced PEC water splitting. Paper presented at 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, AUG 19-23, 2018, Boston, MA. Abstracts of Papers of the American Chemical Society, 256
Öppna denna publikation i ny flik eller fönster >>Double donor Sb5+doped hematite (Fe3+) photoanodes for surface-enhanced PEC water splitting
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2018 (Engelska)Ingår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 256Artikel i tidskrift, Meeting abstract (Övrigt vetenskapligt) Published
Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2018
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:umu:diva-153144 (URN)000447600002312 ()
Konferens
256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, AUG 19-23, 2018, Boston, MA
Tillgänglig från: 2018-11-07 Skapad: 2018-11-07 Senast uppdaterad: 2021-08-27Bibliografiskt granskad
Sandström, R., Ekspong, J., Annamalai, A., Sharifi, T., Klechikov, A. & Wågberg, T. (2018). Fabrication of microporous layer - free hierarchical gas diffusion electrode as a low Pt-loading PEMFC cathode by direct growth of helical carbon nanofibers. RSC Advances, 8(72), 41566-41574
Öppna denna publikation i ny flik eller fönster >>Fabrication of microporous layer - free hierarchical gas diffusion electrode as a low Pt-loading PEMFC cathode by direct growth of helical carbon nanofibers
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2018 (Engelska)Ingår i: RSC Advances, E-ISSN 2046-2069, Vol. 8, nr 72, s. 41566-41574Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Improving interfacial contact between each component in the proton exchange membrane fuel cell (PEMFC) can lead to a significant increase in power density and Pt utilization. In this work, the junction between the catalyst layer and gas diffusion layer (GDL) is greatly enhanced through direct attachment of helical carbon nanofibers, giving rise to a hierarchical structure within the electrical interconnections. The alternative novel GDL is produced by spraying a thin layer of Pd2C60 precursor on commercial carbon paper, followed by chemical vapor deposition growth resulting in a surface morphology of well-attached nanofibers surrounding the microfibers present in the commercial carbon paper. Subsequent solvothermal deposition of platinum nanoparticles allowed evaluation of its suitability as gas diffusion electrode in cathodic H-2/O-2 PEMFC environment. A combination of lowered charge transfer resistance and enhanced Pt-utilization is attributed to its unique wire-like appearance and its robust properties. The fabricated microporous layer - free GDL is suitable for relatively aggressive membrane electrode assembly fabrication procedures and is produced by industrially favorable techniques, rendering it capable of efficiently supporting small amounts of precious metal catalyst nanoparticles in various PEM applications.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2018
Nationell ämneskategori
Materialkemi Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:umu:diva-155124 (URN)10.1039/c8ra07569g (DOI)000453914300053 ()2-s2.0-85058569317 (Scopus ID)
Forskningsfinansiär
KempestiftelsernaEnergimyndighetenVetenskapsrådet
Tillgänglig från: 2019-01-08 Skapad: 2019-01-08 Senast uppdaterad: 2023-03-23Bibliografiskt granskad
Annamalai, A., Sandström, R., Gracia-Espino, E., Boulanger, N., Boily, J.-F., Mühlbacher, I., . . . Wågberg, T. (2018). Influence of Sb5+ as a Double Donor on Hematite (Fe3+) Photoanodes for Surface-Enhanced Photoelectrochemical Water Oxidation. ACS Applied Materials and Interfaces, 10(19), 16467-16473
Öppna denna publikation i ny flik eller fönster >>Influence of Sb5+ as a Double Donor on Hematite (Fe3+) Photoanodes for Surface-Enhanced Photoelectrochemical Water Oxidation
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2018 (Engelska)Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 19, s. 16467-16473Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

To exploit the full potential of hematite (α-Fe2O3) as an efficient photoanode for water oxidation, the redox processes occurring at the Fe2O3/electrolyte interface need to be studied in greater detail. Ex situ doping is an excellent technique to introduce dopants onto the photoanode surface and to modify the photoanode/electrolyte interface. In this context, we selected antimony (Sb5+) as the ex situ dopant because it is an effective electron donor and reduces recombination effects and concurrently utilize the possibility to tuning the surface charge and wettability. In the presence of Sb5+ states in Sb-doped Fe2O3 photoanodes, as confirmed by X-ray photoelectron spectroscopy, we observed a 10-fold increase in carrier concentration (1.1 × 1020 vs 1.3 × 1019 cm–3) and decreased photoanode/electrolyte charge transfer resistance (∼990 vs ∼3700 Ω). Furthermore, a broad range of surface characterization techniques such as Fourier-transform infrared spectroscopy, ζ-potential, and contact angle measurements reveal that changes in the surface hydroxyl groups following the ex situ doping also have an effect on the water splitting capability. Theoretical calculations suggest that Sb5+ can activate multiple Fe3+ ions simultaneously, in addition to increasing the surface charge and enhancing the electron/hole transport properties. To a greater extent, the Sb5+- surface-doped determines the interfacial properties of electrochemical charge transfer, leading to an efficient water oxidation mechanism.

Ort, förlag, år, upplaga, sidor
American Chemical Society (ACS), 2018
Nyckelord
hematite, ex situ doping, Fe2O3-Sb, water splitting, Sb5+, Fe3+, surface charge, double donors
Nationell ämneskategori
Materialkemi Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:umu:diva-148990 (URN)10.1021/acsami.8b02147 (DOI)000432753800027 ()29663796 (PubMedID)2-s2.0-85046257587 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet, 2017-04862Carl Tryggers stiftelse för vetenskaplig forskning , CTS-16-161Energimyndigheten, 45419-1
Tillgänglig från: 2018-06-14 Skapad: 2018-06-14 Senast uppdaterad: 2022-04-04Bibliografiskt granskad
Ekspong, J., Sandström, R., Rajukumar, L. P., Terrones, M., Wågberg, T. & Gracia-Espino, E. (2018). Stable Sulfur‐Intercalated 1T′ MoS2 on Graphitic Nanoribbons as Hydrogen Evolution Electrocatalyst. Advanced Functional Materials, 28(46), Article ID 1802744.
Öppna denna publikation i ny flik eller fönster >>Stable Sulfur‐Intercalated 1T′ MoS2 on Graphitic Nanoribbons as Hydrogen Evolution Electrocatalyst
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2018 (Engelska)Ingår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 46, artikel-id 1802744Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The metastable 1T′ polymorph of molybdenum disulfide (MoS2) has shown excellent catalytic activity toward the hydrogen evolution reaction (HER) in water‐splitting applications. Its basal plane exhibits high catalytic activity comparable to the edges in 2H MoS2 and noble metal platinum. However, the production and application of this polymorph are limited by its lower energetic stability compared to the semiconducting 2H MoS2 phase. Here, the production of stable intercalated 1T′ MoS2 nanosheets attached on graphitic nanoribbons is reported. The intercalated 1T′ MoS2 exhibits a stoichiometric S:Mo ratio of 2.3 (±0.1):1 with an expanded interlayer distance of 10 Å caused by a sulfur‐rich intercalation agent and is stable at room temperature for several months even after drying. The composition, structure, and catalytic activity toward HER are investigated both experimentally and theoretically. It is concluded that the 1T′ MoS2 phase is stabilized by the intercalated agents, which further improves the basal planes′ catalytic activity toward HER.

Ort, förlag, år, upplaga, sidor
WILEY-VCH VERLAG GMBH, 2018
Nyckelord
DFT calculations, hydrogen evolution reaction, intercalation, MoS2, transition metal chalcogenides
Nationell ämneskategori
Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:umu:diva-154948 (URN)10.1002/adfm.201802744 (DOI)000449887300019 ()2-s2.0-85054188827 (Scopus ID)
Tillgänglig från: 2019-01-07 Skapad: 2019-01-07 Senast uppdaterad: 2023-03-23Bibliografiskt granskad
Sandström, R., Gracia-Espino, E., Hu, G., Shchukarev, A., Ma, J. & Wågberg, T. (2018). Yttria stabilized and surface activated platinum (PtxYOy) nanoparticles through rapid microwave assisted synthesis for oxygen reduction reaction. Nano Energy, 46, 141-149
Öppna denna publikation i ny flik eller fönster >>Yttria stabilized and surface activated platinum (PtxYOy) nanoparticles through rapid microwave assisted synthesis for oxygen reduction reaction
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2018 (Engelska)Ingår i: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 46, s. 141-149Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The enhancement of platinum (Pt) based catalysts for the oxygen reduction reaction (ORR) by addition of rare earth metals represents a promising strategy to achieve high activity yet low content of the precious metal and concurrently addresses stability issues experienced by traditional late transition metal doping. Improvement in Pt utilization is essential for vehicular applications where material cost and abundancy is a great concern. Here we report a fast and efficient production route of yttria-stabilized platinum nanoparticles (PtxYOy) using a conventional household microwave oven. ORR performance showed a significant improvement and an optimum activity at a 3:1 Pt:Y ratio outperforming that of commercial Pt-Vulcan with a doubled specific activity. Incorporation of Y is evidenced by extended X-ray absorption fine structure and energy dispersive X-ray analysis, while significant amounts of integrated Y2O3 species are detected by X-ray photoelectron spectroscopy. Density functional theory calculations suggest surface migration and oxidation of Y, forming stable superficial yttrium oxide species with low negative enthalpies of formation. The robustness of PtxYOy is shown experimentally and through theoretical arguments demonstrating that surface yttria acts as a stabilizing agent and promoter of highly active ORR sites on the remaining Pt surface, surpassing even the Pt3Y alloy configuration.

Ort, förlag, år, upplaga, sidor
Elsevier, 2018
Nyckelord
Yttrium, Platinum, Nanoparticles, Catalysis, Hydrogen fuel cells, Oxygen reduction
Nationell ämneskategori
Oorganisk kemi Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:umu:diva-144503 (URN)10.1016/j.nanoen.2018.01.038 (DOI)000427924000017 ()2-s2.0-85041413689 (Scopus ID)
Tillgänglig från: 2018-02-05 Skapad: 2018-02-05 Senast uppdaterad: 2023-03-23Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-6830-2174

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