Abstract
The development of efficient and low-cost electrocatalysts for the oxygen evolution reaction (OER) is critical for improving the efficiency of water electrolysis. Here, we report a strategy using Fe substitution to enable the inactive spinel CoAl2O4 to become highly active and superior to the benchmark IrO2. The Fe substitution is revealed to facilitate surface reconstruction into active Co oxyhydroxides under OER conditions. It also activates deprotonation on the reconstructed oxyhydroxide to induce negatively charged oxygen as an active site, thus significantly enhancing the OER activity of CoAl2O4. Furthermore, it promotes the pre-oxidation of Co and introduces great structural flexibility due to the uplift of the oxygen 2p levels. This results in the accumulation of surface oxygen vacancies along with lattice oxygen oxidation that terminates as Al3+ leaches, preventing further reconstruction. We showcase a promising way to achieve tunable electrochemical reconstruction by optimizing the electronic structure for low-cost and robust spinel oxide OER catalysts.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 digital issues and online access to articles
$119.00 per year
only $9.92 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
Data availability
The data related to this study are available from the authors upon reasonable request.
References
Suntivich, J. et al. A perovskite oxide optimized for oxygen evolution catalysis from molecular orbital principles. Science 334, 1383–1385 (2011).
Grimaud, A., Hong, W. T., Shao-Horn, Y. & Tarascon, J. M. Anionic redox processes for electrochemical devices. Nat. Mater. 15, 121–126 (2016).
Hong, W. T. et al. Toward the rational design of non-precious transition metal oxides for oxygen electrocatalysis. Energy Environ. Sci. 8, 1404–1427 (2015).
Lee, Y. et al. Synthesis and activities of rutile IrO2 and RuO2 nanoparticles for oxygen evolution in acid and alkaline solutions. J. Phys. Chem. Lett. 3, 399–404 (2012).
Chao, W. et al. Cations in octahedral sites: a descriptor for oxygen electrocatalysis on transition-metal spinels. Adv. Mater. 29, 1606800 (2017).
Fabbri, E. et al. Dynamic surface self-reconstruction is the key of highly active perovskite nano-electrocatalysts for water splitting. Nat. Mater. 16, 925–931 (2017).
Hsu, C.-S. et al. Valence- and element-dependent water oxidation behaviors: in situ X-ray diffraction, absorption and electrochemical impedance spectroscopies. Phys. Chem. Chem. Phys. 19, 8681–8693 (2017).
Risch, M. et al. Structural changes of cobalt-based perovskites upon water oxidation investigated by EXAFS. J. Phys. Chem. C 117, 8628–8635 (2013).
Bergmann, A. et al. Reversible amorphization and the catalytically active state of crystalline Co3O4 during oxygen evolution. Nat. Commun. 6, 8625 (2015).
Wang, H.-Y. et al. In operando identification of geometrical-site-dependent water oxidation activity of spinel Co3O4. J. Am. Chem. Soc. 138, 36–39 (2016).
Smith, R. D. L. et al. Spectroscopic identification of active sites for the oxygen evolution reaction on iron-cobalt oxides. Nat. Commun. 8, 2022 (2017).
Görlin, M. et al. Tracking catalyst redox states and reaction dynamics in Ni–Fe oxyhydroxide oxygen evolution reaction electrocatalysts: the role of catalyst support and electrolyte pH. J. Am. Chem. Soc. 139, 2070–2082 (2017).
Zhu, Y. G. et al. Unleashing the power and energy of LiFePO4-based redox flow lithium battery with a bifunctional redox mediator. J. Am. Chem. Soc. 139, 6286–6289 (2017).
Walsh, A., Yan, Y., Al-Jassim, M. M. & Wei, S.-H. Electronic, energetic and chemical effects of intrinsic defects and Fe-doping of CoAl2O4: a DFT+U study. J. Phys. Chem. C 112, 12044–12050 (2008).
Terada, Y. et al. In situ XAFS analysis of Li(Mn, M)2O4 (M = Cr, Co, Ni) 5 V cathode materials for lithium-ion secondary batteries. J. Solid State Chem. 156, 286–291 (2001).
Burke, L. D. & Murphy, O. J. Cyclic voltammetry as a technique for determining the surface area of RuO2 electrodes. J. Electroanal. Chem. 96, 19–27 (1979).
Stoerzinger, K. A., Qiao, L., Biegalski, M. D. & Shao-Horn, Y. Orientation-dependent oxygen evolution activities of rutile IrO2 and RuO2. J. Phys. Chem. Lett. 5, 1636–1641 (2014).
Yeo, B. S. & Bell, A. T. Enhanced activity of gold-supported cobalt oxide for the electrochemical evolution of oxygen. J. Am. Chem. Soc. 133, 5587–5593 (2011).
Kanan, M. W. et al. Structure and valency of a cobalt–phosphate water oxidation catalyst determined by in situ X-ray spectroscopy. J. Am. Chem. Soc. 132, 13692–13701 (2010).
Nkeng, P. et al. Characterization of spinel-type cobalt and nickel oxide thin films by X-ray near grazing diffraction, transmission and reflectance spectroscopies, and cyclic voltammetry. J. Electrochem. Soc. 142, 1777–1783 (1995).
McAlpin, J. G. et al. EPR evidence for Co(iv) species produced during water oxidation at neutral pH. J. Am. Chem. Soc. 132, 6882–6883 (2010).
Costentin, C., Porter, T. R. & Saveant, J. M. How do pseudocapacitors store energy? Theoretical analysis and experimental illustration. ACS Appl. Mater. Interfaces 9, 8649–8658 (2017).
Wang, Z. L., Bentley, J. & Evans, N. D. Valence state mapping of cobalt and manganese using near-edge fine structures. Micron 31, 355–362 (2000).
Trześniewski, B. J. et al. In situ observation of active oxygen species in Fe-containing Ni-based oxygen evolution catalysts: the effect of pH on electrochemical activity. J. Am. Chem. Soc. 137, 15112–15121 (2015).
Yang, C., Fontaine, O., Tarascon, J. M. & Grimaud, A. Chemical recognition of active oxygen species on the surface of oxygen evolution reaction electrocatalysts. Angew. Chem. Int. Ed. 56, 8652–8656 (2017).
Zhang, M., de Respinis, M. & Frei, H. Time-resolved observations of water oxidation intermediates on a cobalt oxide nanoparticle catalyst. Nat. Chem. 6, 362–367 (2014).
Grimaud, A. et al. Activating lattice oxygen redox reactions in metal oxides to catalyse oxygen evolution. Nat. Chem. 9, 457–465 (2017).
Lee, Y.-L. et al. Prediction of solid oxide fuel cell cathode activity with first-principles descriptors. Energy Environ. Sci. 4, 3966–3970 (2011).
Mefford, J. T. et al. Water electrolysis on La1 − xSrxCoO3 − δ perovskite electrocatalysts. Nat. Commun. 7, 11053 (2016).
Cheng, X. et al. Oxygen evolution reaction on La1 – xSrxCoO3 perovskites: a combined experimental and theoretical study of their structural, electronic and electrochemical properties. Chem. Mater. 27, 7662–7672 (2015).
Grimaud, A. et al. Double perovskites as a family of highly active catalysts for oxygen evolution in alkaline solution. Nat. Commun. 4, 2439 (2013).
Zhou, Y. et al. Superexchange effects on oxygen reduction activity of edge-sharing [CoxMn1 − xO6] octahedra in spinel oxide. Adv. Mater. 30, 1705407 (2018).
Hong, W. T. et al. Charge-transfer-energy-dependent oxygen evolution reaction mechanisms for perovskite oxides. Energy Environ. Sci. 10, 2190–2200 (2017).
Rong, X., Parolin, J. & Kolpak, A. M. A fundamental relationship between reaction mechanism and stability in metal oxide catalysts for oxygen evolution. ACS Catal. 6, 1153–1158 (2016).
Goodenough, J. B. Perspective on engineering transition-metal oxides. Chem. Mater. 26, 820–829 (2013).
May, K. J. et al. Influence of oxygen evolution during water oxidation on the surface of perovskite oxide catalysts. J. Phys. Chem. Lett. 3, 3264–3270 (2012).
Bajdich, M. et al. Theoretical investigation of the activity of cobalt oxides for the electrochemical oxidation of water. J. Am. Chem. Soc. 135, 13521–13530 (2013).
Chivot, J. et al. New insight in the behaviour of Co–H2O system at 25–150 °C, based on revised Pourbaix diagrams. Corros. Sci. 50, 62–69 (2008).
Dau, H., Liebisch, P. & Haumann, M. X-ray absorption spectroscopy to analyze nuclear geometry and electronic structure of biological metal centers—potential and questions examined with special focus on the tetra-nuclear manganese complex of oxygenic photosynthesis. Anal. Bioanal. Chem. 376, 562–583 (2003).
Newville, M. IFEFFIT: interactive XAFS analysis and FEFF fitting. J. Synchrotron Radiat. 8, 322–324 (2001).
Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558–561 (1993).
Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Tan, H., Verbeeck, J., Abakumov, A. & Van Tendeloo, G. Oxidation state and chemical shift investigation in transition metal oxides by EELS. Ultramicroscopy 116, 24–33 (2012).
Jung, S. et al. Benchmarking nanoparticulate metal oxide electrocatalysts for the alkaline water oxidation reaction. J. Mater. Chem. A 4, 3068–3076 (2016).
Kim, N.-I. et al. Enhancing activity and stability of cobalt oxide electrocatalysts for the oxygen evolution reaction via transition metal doping. J. Electrochem. Soc. 163, F3020–F3028 (2016).
Acknowledgements
T.W., S.S. and J.S. contributed equally to this work. The authors acknowledge support from the Singapore Ministry of Education Tier 2 Grant (MOE2017-T2-1-009) and the Singapore National Research Foundation under its Campus for Research Excellence and Technological Enterprise (CREATE) programme. The authors also thank the Facility for Analysis, Characterisation, Testing and Simulation (FACTS) in Nanyang Technological University for materials characterizations and the XAFCA beamline of the Singapore Synchrotron Light Source for XAFS characterization.
Author information
Authors and Affiliations
Contributions
T.W., S.S., A.G. and Z.J.X. conceived the original concept and initiated the project. T.W. prepared the materials and performed electrochemical and XRD measurements. S.S. helped design the set-up for in situ XAS measurements. S.X. and T.W. carried out the XAS measurements. Y.D. and T.W. processed and analysed the XAS data. J.S. worked on the DFT calculations and analysis. W.A.S., C.L.G. and B.C. carried out HRTEM and STEM-EELS investigations. L.Z. conducted the measurements in the MEA system. L.Z., H.W., H.Li and G.G.S. analysed the MEA results. T.W. wrote the manuscript with input from all authors, and Z.J.X., A.G. and S.S. revised the manuscript.
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary information
Supplementary Information
Supplementary Figs. 1–18, Supplementary Notes 1–2, Supplementary Tables 1–11 and Supplementary references.
Supplementary Data 1
Atomic coordinates of the optimized computational models.
Rights and permissions
About this article
Cite this article
Wu, T., Sun, S., Song, J. et al. Iron-facilitated dynamic active-site generation on spinel CoAl2O4 with self-termination of surface reconstruction for water oxidation. Nat Catal 2, 763–772 (2019). https://doi.org/10.1038/s41929-019-0325-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s41929-019-0325-4
This article is cited by
-
Active learning guides discovery of a champion four-metal perovskite oxide for oxygen evolution electrocatalysis
Nature Materials (2024)
-
Electric-field-assisted proton coupling enhanced oxygen evolution reaction
Nature Communications (2024)
-
Stabilization of layered lithium-rich manganese oxide for anion exchange membrane fuel cells and water electrolysers
Nature Catalysis (2024)
-
Dual-site segmentally synergistic catalysis mechanism: boosting CoFeSx nanocluster for sustainable water oxidation
Nature Communications (2024)
-
Distance effect of single atoms on stability of cobalt oxide catalysts for acidic oxygen evolution
Nature Communications (2024)