Records |
Author |
Zheng, Y.-R.; Vernieres, J.; Wang, Z.; Zhang, K.; Hochfilzer, D.; Krempl, K.; Liao, T.-W.; Presel, F.; Altantzis, T.; Fatermans, J.; Scott, S.B.; Secher, N.M.; Moon, C.; Liu, P.; Bals, S.; Van Aert, S.; Cao, A.; Anand, M.; Nørskov, J.K.; Kibsgaard, J.; Chorkendorff, I. |
Title |
Monitoring oxygen production on mass-selected iridium–tantalum oxide electrocatalysts |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nature Energy |
Abbreviated Journal |
Nat Energy |
Volume |
|
Issue |
|
Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Development of low-cost and high-performance oxygen evolution reaction catalysts is key to implementing polymer electrolyte membrane water electrolyzers for hydrogen production. Iridium-based oxides are the state-of-the-art acidic oxygen evolution reactio catalysts but still suffer from inadequate activity and stability, and iridium's scarcity motivates the discovery of catalysts with lower iridium loadings. Here we report a mass-selected iridium-tantalum oxide catalyst prepared by a magnetron-based cluster source with considerably reduced noble-metal loadings beyond a commercial IrO2 catalyst. A sensitive electrochemistry/mass-spectrometry instrument coupled with isotope labelling was employed to investigate the oxygen production rate under dynamic operating conditions to account for the occurrence of side reactions and quantify the number of surface active sites. Iridium-tantalum oxide nanoparticles smaller than 2 nm exhibit a mass activity of 1.2 ± 0.5 kA “g” _“Ir” ^“-1” and a turnover frequency of 2.3 ± 0.9 s-1 at 320 mV overpotential, which are two and four times higher than those of mass-selected IrO2, respectively. Density functional theory calculations reveal that special iridium coordinations and the lowered aqueous decomposition free energy might be responsible for the enhanced performance. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000728458000001 |
Publication Date |
2021-12-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2058-7546 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
95 |
Open Access |
OpenAccess |
Notes |
Y.-R.Z. and Z.W acknowledge funding from the Toyota Research Institute. This project has received funding from VILLUM FONDEN (grant no. 9455) and the European Research Council under the European Union’s Horizon 2020 research and innovation programme (grants no. 741860-CLUNATRA, no. 815128−REALNANO and no. 770887−PICOMETRICS). S.B. and S.V.A. acknowledge funding from the Research Foundation Flanders (FWO, G026718N and G050218N). T.A. acknowledges the University of Antwerp Research Fund (BOF). STEM measurements were supported by the European Union's Horizon 2020 Research Infrastructure-Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3.; sygmaSB |
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:184794 |
Serial |
6903 |
Permanent link to this record |
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Author |
Perez, A.J.; Jacquet, Q.; Batuk, D.; Iadecola, A.; Saubanere, M.; Rousse, G.; Larcher, D.; Vezin, H.; Doublet, M.-L.; Tarascon, J.-M. |
Title |
Approaching the limits of cationic and anionic electrochemical activity with the Li-rich layered rocksalt Li3IrO4 |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature energy |
Abbreviated Journal |
Nat Energy |
Volume |
2 |
Issue |
12 |
Pages |
954-962 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The Li-rich rocksalt oxides Li2MO3 (M = 3d/4d/5d transition metal) are promising positive-electrode materials for Li-ion batteries, displaying capacities exceeding 300 mAh g(-1) thanks to the participation of the oxygen non-bonding O(2p) orbitals in the redox process. Understanding the oxygen redox limitations and the role of the O/M ratio is therefore crucial for the rational design of materials with improved electrochemical performances. Here we push oxygen redox to its limits with the discovery of a Li3IrO4 compound (O/M = 4) that can reversibly take up and release 3.5 electrons per Ir and possesses the highest capacity ever reported for any positive insertion electrode. By quantitatively monitoring the oxidation process, we demonstrate the material's instability against O-2 release on removal of all Li. Our results show that the O/M parameter delineates the boundary between the material's maximum capacity and its stability, hence providing valuable insights for further development of high-capacity materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000430218300001 |
Publication Date |
2017-12-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2058-7546 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
55 |
Open Access |
Not_Open_Access |
Notes |
; We thank P. Pearce for providing the beta-Li<INF>2</INF>IrO<INF>3</INF> and L. Lemarquis for helping in the DEMS experiment. We are particularly grateful to S. Belin, V. Briois and L. Stievano for helpful discussions on XAS analysis and synchrotron SOLEIL (France) for providing beamtime at the ROCK beamline (financed by the French National Research Agency (ANR) as part of the 'Investissements d'Avenir' programme, reference: ANR-10-EQPX-45). A.J.P and A. I. acknowledge the GdR C(RS) 2 for the workshop organized on a chemometric approach for XAS data analysis. V. Nassif is acknowledged for her help during neutron diffraction experiments performed at Institut Laue Langevin on D1B. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is gratefully acknowledged. This work has been performed with the support of the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116 ARPEMA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:150926 |
Serial |
4962 |
Permanent link to this record |