Decoupling the catalytic and degradation mechanisms of cobalt active sites during acidic water oxidation
Source abstract
Abstract
Abstract Advancement of iridium-free catalysts for the low-pH oxygen evolution reaction (OER) is required to enable multi-gigawatt-scale proton-exchange water electrolysis. Cobalt-based materials might address this requirement, but little is known about the mechanism of operation of these OER catalysts at low pH. Here we investigate the nature and evolution of the active cobalt sites along with charge- and mass-transfer processes that support their catalytic function within a cobalt–iron–lead oxide material using in situ spectroscopic, gravimetric and electrochemical techniques. We demonstrate that corrosion of the cobalt sites and their reformation through electrooxidation of dissolved Co2+ do not affect the catalytic mechanism and are decoupled from the OER. The OER-coupled charge transfer is supported by Co(3+δ)+-oxo-species, which are structurally different from those reported for alkaline/near-neutral conditions and are formed on a relatively slow timescale of minutes. These mechanistic insights might assist in developing genuinely practical catalysts for this vital technology.
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Research context
OpenAlex topics: Electrocatalysts for Energy Conversion · Catalytic Processes in Materials Science · Nanomaterials for catalytic reactions
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (67)
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1. Kibsgaard, J. & Chorkendorff, I. Considerations for the scaling-up of water splitting catalysts. Nat. Energy 4, 430–433 (2019).10.1038/s41560-019-0407-1 ↗
2. Pham, C. V., Escalera-López, D., Mayrhofer, K., Cherevko, S. & Thiele, S. Essentials of high performance water electrolyzers—from catalyst layer materials to electrode engineering. Adv. Energy Mater. 11, 2101998 (2021).10.1002/aenm.202101998 ↗
3. Chen, F.-Y., Wu, Z.-Y., Adler, Z. & Wang, H. Stability challenges of electrocatalytic oxygen evolution reaction: from mechanistic understanding to reactor design. Joule 5, 1704–1731 (2021).10.1016/j.joule.2021.05.005 ↗
4. Li, A. et al. Enhancing the stability of cobalt spinel oxide towards sustainable oxygen evolution in acid. Nat. Catal. 5, 109–118 (2022).10.1038/s41929-021-00732-9 ↗
5. Cao, J., Zhang, D., Ren, B., Song, P. & Xu, W. Tungsten single atoms incorporated in cobalt spinel oxide for highly efficient electrocatalytic oxygen evolution in acid. Energy Environ. Sci. 17, 5911–5921 (2024).10.1039/D4EE01783H ↗
6. Chong, L. et al. La- and Mn-doped cobalt spinel oxygen evolution catalyst for proton exchange membrane electrolysis. Science 380, 609–616 (2023).10.1126/science.ade1499 ↗
7. Tran-Phu, T. et al. Nanoscale TiO2 coatings improve the stability of an Earth-abundant cobalt oxide catalyst during acidic water oxidation. ACS Appl. Mater. Interfaces 14, 33130–33140 (2022).10.1021/acsami.2c05849 ↗
8. Ta, X. M. C. et al. Optimal coatings of Co3O4 anodes for acidic water electrooxidation. Small 20, 2304650 (2023).10.1002/smll.202304650 ↗
9. Moreno-Hernandez, I. A. et al. Crystalline nickel manganese antimonate as a stable water-oxidation catalyst in aqueous 1.0 M H2SO4. Energy Environ. Sci. 10, 2103–2108 (2017).10.1039/C7EE01486D ↗
10. Luke, S. et al. Mixed metal–antimony oxide nanocomposites: low pH water oxidation electrocatalysts with outstanding durability at ambient and elevated temperatures. J. Mater. Chem. A 9, 27468–27484 (2021).10.1039/D1TA07293E ↗
11. Du, H.-L. et al. Durable electrooxidation of acidic water catalysed by a cobalt-bismuth-based oxide composite: an unexpected role of the F-doped SnO2 substrate. ChemCatChem 14, e202200013 (2022).10.1002/cctc.202200013 ↗
12. Luke, S. et al. High performance acidic water electrooxidation catalysed by manganese-antimony oxides promoted by secondary metals. EES Catalysis 1, 730–741 (2023).10.1039/D3EY00046J ↗
13. Ram, R. et al. Water-hydroxide trapping in cobalt tungstate for proton exchange membrane water electrolysis. Science 384, 1373–1380 (2024).10.1126/science.adk9849 ↗
14. Geiger, S. et al. The stability number as a metric for electrocatalyst stability benchmarking. Nat. Catal. 1, 508–515 (2018).10.1038/s41929-018-0085-6 ↗
15. Bloor, L. G., Molina, P. I., Symes, M. D. & Cronin, L. Low pH electrolytic water splitting using Earth-abundant metastable catalysts that self-assemble in situ. J. Am. Chem. Soc. 136, 3304–3311 (2014).10.1021/ja5003197 ↗
16. Chatti, M. et al. Intrinsically stable in situ generated electrocatalyst for long-term oxidation of acidic water at up to 80 °C. Nat. Catal. 2, 457–465 (2019).10.1038/s41929-019-0277-8 ↗
17. Bonke, S. A. et al. Electrolysis of natural waters contaminated with transition-metal ions: identification of a metastable FePb-based oxygen-evolution catalyst operating in weakly acidic solutions. ChemPlusChem 83, 704–710 (2018).10.1002/cplu.201800020 ↗
18. Thorarinsdottir, A. E., Costentin, C., Veroneau, S. S. & Nocera, D. G. p-Block metal oxide noninnocence in the oxygen evolution reaction in acid: the case of bismuth oxide. Chem. Mater. 34, 826–835 (2022).10.1021/acs.chemmater.1c03801 ↗
19. Simondson, D. et al. Stable acidic water oxidation with a cobalt–iron–lead oxide catalyst operating via a cobalt-selective self-healing mechanism. Angew. Chem. Int. Ed. 60, 15821–15826 (2021).10.1002/anie.202104123 ↗
20. Wang, J. et al. Heterostructure boosts a noble-metal-free oxygen-evolving electrocatalyst in acid. Energy Environ. Sci. 17, 5972–5983 (2024).10.1039/D4EE00189C ↗
21. Risch, M. et al. Water oxidation by amorphous cobalt-based oxides: in situ tracking of redox transitions and mode of catalysis. Energy Environ. Sci. 8, 661–674 (2015).10.1039/C4EE03004D ↗
22. King, H. J. et al. Photon-induced, timescale, and electrode effects critical for the in situ X-ray spectroscopic analysis of electrocatalysts: the water oxidation case. J. Phys. Chem. C 123, 28533–28549 (2019).10.1021/acs.jpcc.9b06944 ↗
23. Liu, S. et al. Phosphate coordination in a water-oxidizing cobalt oxide electrocatalyst revealed by X-ray absorption spectroscopy at the phosphorus K-edge. Catalysts 13, 1151 (2023).10.3390/catal13081151 ↗
24. Mohammadi, M. R. et al. Exploring the limits of self-repair in cobalt oxide films for electrocatalytic water oxidation. ACS Catal. 10, 7990–7999 (2020).10.1021/acscatal.0c01944 ↗
25. Liu, S. et al. Electrocatalytic water oxidation at neutral pH–deciphering the rate constraints for an amorphous cobalt-phosphate catalyst system. Adv. Energy Mater. 12, 2202914 (2022).10.1002/aenm.202202914 ↗
26. Pfeifer, V. et al. The electronic structure of iridium oxide electrodes active in water splitting. Phys. Chem. Chem. Phys. 18, 2292–2296 (2016).10.1039/C5CP06997A ↗
27. Pfeifer, V. et al. In situ observation of reactive oxygen species forming on oxygen-evolving iridium surfaces. Chem. Sci. 8, 2143–2149 (2017).10.1039/C6SC04622C ↗
28. Spanos, I. et al. Standardized benchmarking of water splitting catalysts in a combined electrochemical flow cell/inductively coupled plasma–optical emission spectrometry (ICP-OES) setup. ACS Catal. 7, 3768–3778 (2017).10.1021/acscatal.7b00632 ↗
29. Papakonstantinou, G., Spanos, I., Dam, A. P., Schlögl, R. & Sundmacher, K. Electrochemical evaluation of the de-/re-activation of oxygen evolving Ir oxide. Phys. Chem. Chem. Phys. 24, 14579–14591 (2022).10.1039/D2CP00828A ↗
30. Zhang, Y., Simonov, A. N., Zhang, J. & Bond, A. M. Fourier transformed alternating current voltammetry in electromaterials research: direct visualisation of important underlying electron transfer processes. Curr. Opin. Electrochem. 10, 72–81 (2018).10.1016/j.coelec.2018.04.016 ↗
31. Knöppel, J. et al. On the limitations in assessing stability of oxygen evolution catalysts using aqueous model electrochemical cells. Nat. Comm. 12, 2231 (2021).10.1038/s41467-021-22296-9 ↗
32. Risch, M. et al. Cobalt−oxo core of a water-oxidizing catalyst film. J. Am. Chem. Soc. 131, 6936–6937 (2009).10.1021/ja902121f ↗
33. Hausmann, J. N., Mebs, S., Dau, H., Driess, M. & Menezes, P. W. Oxygen evolution activity of amorphous cobalt oxyhydroxides: interconnecting precatalyst reconstruction, long-range order, buffer-binding, morphology, mass transport, and operation temperature. Adv. Mater. 34, 2207494 (2022).10.1002/adma.202207494 ↗
34. Hocking, R. K. & Solomon, E. I. in Molecular Electronic Structures of Transition Metal Complexes I Vol. 142 (eds Mingos, D. M. P. et al.) 155–184 (Springer, 2012).10.1007/430_2011_60 ↗
35. Kerr, B. V. et al. Characterization of energy materials with X-ray absorption spectroscopy—advantages, challenges, and opportunities. Energy Fuels 36, 2369–2389 (2022).10.1021/acs.energyfuels.1c04072 ↗
36. Yoon, W.-S. et al. Oxygen contribution on Li-ion intercalation−deintercalation in LiCoO2 investigated by O K-edge and Co L-edge X-ray absorption spectroscopy. J. Phys. Chem. B 106, 2526–2532 (2002).10.1021/jp013735e ↗
37. Bonke, S. A., Bond, A. M., Spiccia, L. & Simonov, A. N. Parameterization of water electrooxidation catalyzed by metal oxides using Fourier transformed alternating current voltammetry. J. Am. Chem. Soc. 138, 16095–16104 (2016).10.1021/jacs.6b10304 ↗
38. Hodgetts, R. Y., Du, H.-L., Nguyen, T. D., MacFarlane, D. & Simonov, A. N. Electrocatalytic oxidation of hydrogen as an anode reaction for the Li-mediated N2 reduction to ammonia. ACS Catal. 12, 5231–5246 (2022).10.1021/acscatal.2c00538 ↗
39. Simondson, D. et al. Mixed silver–bismuth oxides: a robust oxygen evolution catalyst operating at low pH and elevated temperatures. ACS Catal. 12, 12912–12926 (2022).10.1021/acscatal.2c03065 ↗
40. Snitkoff-Sol, R. Z., Rimon, O., Bond, A. M. & Elbaz, L. Direct measurement of the oxygen reduction reaction kinetics on iron phthalocyanine using advanced transient voltammetry. Nat. Catal. 7, 139–147 (2024).10.1038/s41929-023-01086-0 ↗
41. Frydendal, R. et al. Benchmarking the stability of oxygen evolution reaction catalysts: the importance of monitoring mass losses. ChemElectroChem 1, 2075–2081 (2014).10.1002/celc.201402262 ↗
42. Pasquini, C. et al. Operando tracking of oxidation-state changes by coupling electrochemistry with time-resolved X-ray absorption spectroscopy demonstrated for water oxidation by a cobalt-based catalyst film. Anal. Bioanal. Chem. 413, 5395–5408 (2021).10.1007/s00216-021-03515-0 ↗
43. Minguzzi, A. et al. Fixed energy X-ray absorption voltammetry. Anal. Chem. 85, 7009–7013 (2013).10.1021/ac401414v ↗
44. Tesch, M. F. & Simonov, A. N. Tracking the transient: real-time exploration of electromaterials by dynamic single energy X-ray spectroelectrochemistry. Curr. Opin. Electrochem 35, 101038 (2022).10.1016/j.coelec.2022.101038 ↗
45. Mizokawa, T. et al. Role of oxygen holes in LixCoO2 revealed by soft X-ray spectroscopy. Phys. Rev. Lett. 111, 056404 (2013).10.1103/PhysRevLett.111.056404 ↗
46. Liu, J. et al. Efficient and stable proton exchange membrane water electrolysis enabled by stress optimization. ACS Cent. Sci. 10, 852–859 (2024).
47. Tesch, M. F. et al. Vacuum compatible flow-cell for high-quality in situ and operando soft X-ray photon-in–photon-out spectroelectrochemical studies of energy materials. Electrochem. Sci. Adv. 2, e2100141 (2022).10.1002/elsa.202100141 ↗
48. Tesch, M. F. et al. Evolution of oxygen–metal electron transfer and metal electronic states during manganese oxide catalyzed water oxidation revealed with in situ soft X-ray spectroscopy. Angew. Chem. Int. Ed. 58, 3426–3432 (2019).10.1002/anie.201810825 ↗
49. Glover, C. et al. Status of the X-ray absorption spectroscopy (XAS) beamline at the Australian synchrotron. AIP Conf.Proc. 882, 884–886 (2007).10.1063/1.2644692 ↗
50. Kappen, P. & Ruben, G. AS-VeRSI, ver. 0.2.1, Computer Program, Sakura: Data Explorer for X-ray Absorption Spectroscopy (XAS) Data (Australian Synchrotron, 2013).
51. Ravel, B. & Newville, M. ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron Radiat. 12, 537–541 (2005).10.1107/S0909049505012719 ↗
52. Tenderholt, A., Hedman, B. & Hodgson, K. O. PySpline: a modern, cross-platform program for the processing of raw averaged XAS edge and EXAFS data. AIP Conf. Proc. 882, 105–107 (2007).10.1063/1.2644442 ↗
53. Aziz, E. F., Xiao, J., Golnak, R. & Tesch, M. LiXEdrom: high energy resolution RIXS station dedicated to liquid investigation at BESSY II. J. Large-Scale Res. Facil. 2, A80 (2016).10.17815/jlsrf-2-85 ↗
54. Haverkort, M. W., Zwierzycki, M. & Andersen, O. K. Multiplet ligand-field theory using Wannier orbitals. Phys. Rev. B 85, 165113 (2012).10.1103/PhysRevB.85.165113 ↗
55. Nørskov, J. K. et al. Origin of the overpotential for oxygen reduction at a fuel-cell cathode. J. Phys. Chem. B 108, 17886–17892 (2004).10.1021/jp047349j ↗
56. Giannozzi, P. et al. QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials. J. Phys. Condens. Matter 21, 395502 (2009).10.1088/0953-8984/21/39/395502 ↗
57. Giannozzi, P. et al. Advanced capabilities for materials modelling with Quantum ESPRESSO. J. Phys. Condens. Matter 29, 465901 (2017).10.1088/1361-648X/aa8f79 ↗
58. Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).10.1103/PhysRevLett.77.3865 ↗
59. Dal Corso, A. Pseudopotentials periodic table: from H to Pu. Comput. Mater. Sci. 95, 337–350 (2014).10.1016/j.commatsci.2014.07.043 ↗
60. Marzari, N., Vanderbilt, D., De Vita, A. & Payne, M. C. Thermal contraction and disordering of the Al(110) surface. Phys. Rev. Lett. 82, 3296–3299 (1999).10.1103/PhysRevLett.82.3296 ↗
61. Shirley, E. L. Ti 1s pre-edge features in rutile: a Bethe–Salpeter calculation. J. Electron. Spectrosc. Relat. Phenom. 136, 77–83 (2004).10.1016/j.elspec.2004.02.134 ↗
62. Abbasi, T. & Abbasi, S. A. ‘Renewable’ hydrogen: prospects and challenges. Renew. Sustain. Energy Rev. 15, 3034–3040 (2011).10.1016/j.rser.2011.02.026 ↗
63. Soininen, J. A. & Shirley, E. L. Scheme to calculate core hole–electron interactions in solids. Phys. Rev. B 64, 165112 (2001).10.1103/PhysRevB.64.165112 ↗
64. Vinson, J. & Rehr, J. J. Ab initio Bethe–Salpeter calculations of the X-ray absorption spectra of transition metals at the L-shell edges. Phys. Rev. B 86, 195135 (2012).10.1103/PhysRevB.86.195135 ↗
65. Vinson, J., Rehr, J. J., Kas, J. J. & Shirley, E. L. Bethe–Salpeter equation calculations of core excitation spectra. Phys. Rev. B 83, 115106 (2011).10.1103/PhysRevB.83.115106 ↗
66. Pehlke, E. & Scheffler, M. Evidence for site-sensitive screening of core holes at the Si and Ge (001) surface. Phys. Rev. Lett. 71, 2338–2341 (1993).10.1103/PhysRevLett.71.2338 ↗
67. Krause, M. O. & Oliver, J. H. Natural widths of atomic K and L levels, Kα X‐ray lines and several KLL Auger lines. J. Phys. Chem. Ref. Data 8, 329–338 (1979).10.1063/1.555595 ↗