umu.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Yttria stabilized and surface activated platinum (PtxYOy) nanoparticles through rapid microwave assisted synthesis for oxygen reduction reaction
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik. Key Laboratory of Chemistry of Plant Resources in Arid Regions, State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, China.
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
Vise andre og tillknytning
2018 (engelsk)Inngår i: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 46, s. 141-149Artikkel i tidsskrift (Fagfellevurdert) 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.

sted, utgiver, år, opplag, sider
Elsevier, 2018. Vol. 46, s. 141-149
Emneord [en]
Yttrium, Platinum, Nanoparticles, Catalysis, Hydrogen fuel cells, Oxygen reduction
HSV kategori
Identifikatorer
URN: urn:nbn:se:umu:diva-144503DOI: 10.1016/j.nanoen.2018.01.038ISI: 000427924000017OAI: oai:DiVA.org:umu-144503DiVA, id: diva2:1180206
Tilgjengelig fra: 2018-02-05 Laget: 2018-02-05 Sist oppdatert: 2019-04-29bibliografisk kontrollert
Inngår i avhandling
1. Innovations in nanomaterials for proton exchange membrane fuel cells
Åpne denne publikasjonen i ny fane eller vindu >>Innovations in nanomaterials for proton exchange membrane fuel cells
2019 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Alternativ tittel[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.

sted, utgiver, år, opplag, sider
Umeå: Umeå University, 2019. s. 88
Emneord
Fuel Cells, Membrane Electrode Assembly, Oxygen Reduction Reaction, Platinum alloy catalyst, Nanoparticles, Gas Diffusion Electrode, Proton Exchange Membrane
HSV kategori
Forskningsprogram
materialvetenskap; fasta tillståndets fysik
Identifikatorer
urn:nbn:se:umu:diva-158501 (URN)978-91-7855-044-9 (ISBN)
Disputas
2019-05-28, N460, Naturvetarhuset, Umeå, 10:15 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2019-05-07 Laget: 2019-04-29 Sist oppdatert: 2019-05-06bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekst

Personposter BETA

Sandström, RobinGracia-Espino, EduardoHu, GuangzhiShchukarev, AndreyWågberg, Thomas

Søk i DiVA

Av forfatter/redaktør
Sandström, RobinGracia-Espino, EduardoHu, GuangzhiShchukarev, AndreyWågberg, Thomas
Av organisasjonen
I samme tidsskrift
Nano Energy

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 289 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf