Tuning the local electronic structure of oxygen vacancies over copper-doped zinc oxide for efficient CO<sub>2</sub> electroreduction

Wang Ke; Liu Dongyu; Liu Limin; Liu Jia; Hu XiaoFei; Li Ping; Li Mingtao; Vasenko Andrey S.; Xiao Chunhui; Ding Shujiang

doi:10.1016/j.esci.2022.08.002

Volume 2 Issue 5

Sep. 2022

Turn off MathJax

Article Contents

Article Navigation > eScience > 2022 > 2(5): 518-528

Wang Ke, Liu Dongyu, Liu Limin, Liu Jia, Hu XiaoFei, Li Ping, Li Mingtao, Vasenko Andrey S., Xiao Chunhui, Ding Shujiang. Tuning the local electronic structure of oxygen vacancies over copper-doped zinc oxide for efficient CO2 electroreduction[J]. eScience, 2022, 2(5): 518-528. doi: 10.1016/j.esci.2022.08.002

Citation:

Wang Ke, Liu Dongyu, Liu Limin, Liu Jia, Hu XiaoFei, Li Ping, Li Mingtao, Vasenko Andrey S., Xiao Chunhui, Ding Shujiang. Tuning the local electronic structure of oxygen vacancies over copper-doped zinc oxide for efficient CO₂ electroreduction[J]. eScience, 2022, 2(5): 518-528. doi: 10.1016/j.esci.2022.08.002

Citation:

Wang Ke, Liu Dongyu, Liu Limin, Liu Jia, Hu XiaoFei, Li Ping, Li Mingtao, Vasenko Andrey S., Xiao Chunhui, Ding Shujiang. Tuning the local electronic structure of oxygen vacancies over copper-doped zinc oxide for efficient CO₂ electroreduction[J]. eScience, 2022, 2(5): 518-528. doi: 10.1016/j.esci.2022.08.002

PDF( 3809 KB)

Tuning the local electronic structure of oxygen vacancies over copper-doped zinc oxide for efficient CO₂ electroreduction

doi: 10.1016/j.esci.2022.08.002

Wang Ke^{a, 1},
Liu Dongyu^{b, c, 1},
Liu Limin^{a, 1},
Liu Jia^d,
Hu XiaoFei^a,
Li Ping^e,
Li Mingtao^b,
Vasenko Andrey S.^c,
Xiao Chunhui^{a
,
,},
Ding Shujiang^a

a.
Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, School of Chemistry, Energy Storage Materials and Chemistry of Shaanxi University Engineering Research Center, Xi'an Jiaotong University, 28 Xianning West Road, Xi'an, 710049, China
b.
International Research Center for Renewable Energy (IRCRE), State Key Laboratory of Multiphase Flow in Power Engineering (MFPE), Xi'an Jiaotong University, 28 Xianning West Road, Xi'an, Shaanxi, 710049, China
c.
HSE University, 101000, Moscow, Russia
d.
College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
e.
CNNC Shaanxi Uranium Enrichment Co., Ltd., Hanzhong, China

More Information

Corresponding author: E-mail address: chunhuixiao@xjtu.edu.cn (C. Xiao)
Received Date: 2022-04-15
Revised Date: 2022-07-29
Accepted Date: 2022-08-11

Available Online: 2022-08-24

Abstract

Abstract

Oxygen vacancies in metal oxides can serve as electron trap centers to capture CO₂ and lower energy barriers for the electrochemical CO₂ reduction reaction (CO₂RR). Under aqueous electrolytes, however, such charge-enriched active sites can be occupied by adsorbed hydrogen (H*) and lose their effectiveness for the CO₂RR. Here, we develop an efficient catalyst consisting of Cu-doped, defect-rich ZnO (Cu–ZnO) for the CO₂RR, which exhibits enhanced CO Faradaic efficiency and current density compared to pristine ZnO. The introduced Cu dopants simultaneously stabilize neighboring oxygen vacancies and modulate their local electronic structure, achieving inhibition of hydrogen evolution and acceleration of the CO₂RR. In a flow cell test, a current density of more than 45 mA cm⁻² and a CO Faradaic efficiency of > 80% is obtained for a Cu–ZnO electrocatalyst in the wide potential range of −0.76 V to −1.06 V vs. Reversible Hydrogen Electrode (RHE). This work opens up great opportunities for dopant-modulated metal oxide catalysts for the CO₂RR.
- CO₂ electroreduction,
- Oxygen vacancy,
- Heteroatom doping,
- Metal oxide catalysts

● A low-valence Cu-doping strategy is proposed to tune the local electronic structure of oxygen vacancies in ZnO.
● The Cu-doped and defect-rich ZnO exhibits enhanced CO Faradaic efficiency and current density compared to pristine ZnO.
● The tuned local electronic structure of oxygen vacancies can weaken the adsorption of H* and optimize the affinity for CO*.
C.H. Xiao proposed the concept. D.Y. Liu, M.T. Li, and Andrey S. Vasenko performed the density functional theory calculations. K. Wang, J. Liu, and P. Li performed the experiments. K. Wang, D.Y. Liu, L.M. Liu, X.F. Hu, and S.J. Ding co-wrote the manuscript. All authors participated in data analysis and manuscript discussion.
Author contributions
Declaration of competing interest
The authors declare no competing financial interests.
¹ These authors contributed equally to this work.

FullText(HTML)

Supplements(1)

eScience-2-5-518.docx

References(60)

References

[1]	D.H. Nam, P. De Luna, A. Rosas-Hernandez, A. Thevenon, F. Li, T. Agapie, J.C. Peters, O. Shekhah, M. Eddaoudi, E.H. Sargent, Molecular enhancement of heterogeneous CO₂ reduction, Nat. Mater. 19 (2020) 266-276. doi: 10.1038/s41563-020-0610-2
[2]	J.D. Yi, D.H. Si, R. Xie, Q. Yin, M.D. Zhang, Q. Wu, G.L. Chai, Y.B. Huang, R Cao, Conductive two-dimensional phthalocyanine-based Metal-organic framework nanosheets for efficient electroreduction of CO₂, Angew. Chem. Int. Ed. 60 (2021) 17108-17114. doi: 10.1002/anie.202104564
[3]	D.L. Meng, M.D. Zhang, D.H. Si, M.J. Mao, Y. Hou, Y.B. Huang, R. Cao, Highly selective tandem electroreduction of CO₂ to ethylene over atomically isolated nickel-nitrogen site/copper nanoparticle catalysts, Angew. Chem. Int. Ed. 60 (2021) 25485-25492. doi: 10.1002/anie.202111136
[4]	J. Yi, Q. Li, S. Chi, Y. Huang, R Cao, Boron-doped covalent triazine framework for efficient CO₂ electroreduction, Chem. Res. Chin. Univ. 38 (2022) 141-146. doi: 10.1007/s40242-021-1384-z
[5]	H. Guo, D.H. Si, H.J. Zhu, Q.X. Li, Y.B. Huang, R. Cao, Ni single-atom sites supported on carbon aerogel for highly efficient electroreduction of carbon dioxide with industrial current densities, eScience 2 (2022) 295-303. doi: 10.1016/j.esci.2022.03.007
[6]	M.D. Zhang, J. D Yi, Y.B. Huang, R Cao, Covalent triazine frameworks-derived N, P dual-doped porous carbons for highly efficient electrochemical reduction of CO₂, Chin. J. Struct. Chem. 40 (2021) 1213-1222.
[7]	K. Jiang, H. Wang, W.B. Cai, H. Wang, Electrochemical tuning of metal oxide for highly selective CO₂ reduction, ACS Nano 11 (2017) 6451-6458. doi: 10.1021/acsnano.7b03029
[8]	J. Li, A. Zitolo, F.A. Garces-Pineda, T. Asset, M. Kodali, P. Tang, J. Arbiol, J.R. Galan-Mascaros, P. Atanassov, I.V. Zenyuk, M.T. Sougrati, F. Jaouen, Metal oxide clusters on nitrogen-doped carbon are highly selective for CO₂ electroreduction to CO, ACS Catal. 11 (2021) 10028-10042. doi: 10.1021/acscatal.1c01702
[9]	J. Wang, G. Wang, J. Zhang, Y. Wang, H. Wu, X. Zheng, J. Ding, X. Han, Y. Deng, W. Hu, Inversely tuning the CO₂ electroreduction and hydrogen evolution activity on metal oxide via heteroatom doping, Angew. Chem. Int. Ed. 60 (2021) 7602-7606. doi: 10.1002/anie.202016022
[10]	J. Zhang, R. Yin, Q. Shao, T. Zhu, X. Huang, Oxygen vacancies in amorphous InOx nanoribbons enhance CO₂ adsorption and activation for CO₂ electroreduction, Angew. Chem. Int. Ed. 58 (2019) 5609-5613. doi: 10.1002/anie.201900167
[11]	Y.X. Duan, Y.T. Zhou, Z. Yu, D.X. Liu, Z. Wen, J.M. Yan, Q. Jiang, Boosting production of HCOOH from CO₂ electroreduction via Bi/CeO_x, Angew. Chem. Int. Ed. 60 (2021) 8798-8802. doi: 10.1002/anie.202015713
[12]	J. Zhang, W. Cai, F.X. Hu, H. Yang, B. Liu, Recent advances in single atom catalysts for the electrochemical carbon dioxide reduction reaction, Chem. Sci. 12 (2021) 6800-6819. doi: 10.1039/D1SC01375K
[13]	F. Meng, C. Dai, Z. Liu, S. Luo, J. Ge, Y. Duan, G. Chen, C. Wei, R.R. Chen, J. Wang. D. Mandler, Z.J. Xu, Methanol electro-oxidation to formate on iron-substituted lanthanum cobaltite perovskite oxides, eScience 2 (2022), 87-94. doi: 10.1016/j.esci.2022.02.001
[14]	S. Gao, Z. Sun, W. Liu, X. Jiao, X. Zu, Q. Hu, Y. Sun, T. Yao, W. Zhang, S. Wei, Y. Xie, Atomic layer confined vacancies for atomic-level insights into carbon dioxide electroreduction, Nat. Commun. 8 (2017) 14503. doi: 10.1038/ncomms14503
[15]	L. Li, Z.J. Zhao, C. Hu, P. Yang, X. Yuan, Y. Wang, L. Zhang, L. Moskaleva, J. Gong, Tuning oxygen vacancies of oxides to promote electrocatalytic reduction of carbon dioxide, ACS Energy Lett. 5 (2020) 552-558. doi: 10.1021/acsenergylett.9b02749
[16]	Z. Geng, X. Kong, W. Chen, H. Su, Y. Liu, F. Cai, G. Wang, J. Zeng, Oxygen vacancies in ZnO nanosheets enhance CO₂ electrochemical reduction to CO, Angew. Chem. Int. Ed. 57 (2018) 6054-6059. doi: 10.1002/anie.201711255
[17]	C. Peng, G. Luo, J. Zhang, M. Chen, Z. Wang, T.K. Sham, L. Zhang, Y. Li, G. Zheng, Double sulfur vacancies by lithium tuning enhance CO₂ electroreduction to n-propanol, Nat. Commun. 12 (2021) 1580. doi: 10.1038/s41467-021-21901-1
[18]	J. Swaminathan, R. Subbiah, V. Singaram, Defect-rich metallic titania (TiO_1.23)-An efficient hydrogen evolution catalyst for electrochemical water splitting, ACS Catal. 6 (2016) 2222-2229. doi: 10.1021/acscatal.5b02614
[19]	T. Ling, T. Zhang, B. Ge, L. Han, L. Zheng, F. Lin, Z. Xu, W.B. Hu, X.W. Du, K. Davey, S.Z. Qiao, Well-dispersed nickel-and zinc-tailored electronic structure of a transition metal oxide for highly active alkaline hydrogen evolution reaction, Adv. Mater. 31 (2019) 1807771. doi: 10.1002/adma.201807771
[20]	S. Zhao, D. Kang, Y. Liu, Y. Wen, X. Xie, H. Yi, X. Tang, Spontaneous formation of asymmetric oxygen vacancies in transition-metal-doped CeO₂ nanorods with improved activity for carbonyl sulfide hydrolysis, ACS Catal. 10 (2020) 11739-11750. doi: 10.1021/acscatal.0c02832
[21]	J. Buckeridge, C.R.A. Catlow, M.R. Farrow, A.J. Logsdail, D.O. Scanlon, T.W. Keal, P. Sherwood, S.M. Woodley, A.A. Sokol, A. Walsh, Deep vs shallow nature of oxygen vacancies and consequent n-type carrier concentrations in transparent conducting oxides, Phys. Rev. Mater. 2 (2018) 54604. doi: 10.1103/PhysRevMaterials.2.054604
[22]	Y. Zhao, Y. Zhao, R. Shi, B. Wang, G.I.N. Waterhouse, L.Z. Wu, C.H. Tung, T. Zhang, Tuning oxygen vacancies in ultrathin TiO₂ nanosheets to boost photocatalytic nitrogen fixation up to 700 nm, Adv. Mater. 31 (2019) 1806482. doi: 10.1002/adma.201806482
[23]	N. Cao, Z. Chen, K. Zang, J. Xu, J. Zhong, J. Luo, X. Xu, G. Zheng, Doping strain induced bi-Ti³⁺ pairs for efficient N₂ activation and electrocatalytic fixation, Nat. Commun. 10 (2019) 2877. doi: 10.1038/s41467-019-10888-5
[24]	Y. Bo, H. Wang, Y. Lin, T. Yang, R. Ye, Y. Li, C. Hu, P. Du, Y. Hu, Z. Liu, R. Long, C. Gao, B. Ye, L. Song, X. Wu, Y. Xiong, Altering hydrogenation pathways in photocatalytic nitrogen fixation by tuning local electronic structure of oxygen vacancy with dopant, Angew. Chem. Int. Ed. 60 (2021) 16085-16092. doi: 10.1002/anie.202104001
[25]	X. Zu, Y. Zhao, X. Li, R. Chen, W. Shao, Z. Wang, J. Hu, J. Zhu, Y. Pan, Y. Sun, Y. Xie, Ultrastable and efficient visible-light-driven CO₂ reduction triggered by regenerative oxygen-vacancies in Bi₂O₂CO₃ nanosheets, Angew. Chem. Int. Ed. 60 (2021) 13840-13846. doi: 10.1002/anie.202101894
[26]	J. Wang, J. Liu, B. Zhang, F. Cheng, Y. Ruan, X. Ji, K. Xu, C. Chen, L. Miao, J. Jiang, Stabilizing the oxygen vacancies and promoting water-oxidation kinetics in cobalt oxides by lower valence-state doping, Nano Energy 53 (2018) 144-151. doi: 10.1016/j.nanoen.2018.08.022
[27]	G. Kresse, J. Hafner, Ab initio molecular dynamics for liquid metals, Phys. Rev. B 47 (1993) 558-561. doi: 10.1103/PhysRevB.47.558
[28]	G. Kresse, J. Hafner, Ab initio molecular-dynamics simulation of the liquid-metal-amorphous-semiconductor transition in germanium, Phys. Rev. B 49 (1994) 14251-14269. doi: 10.1103/PhysRevB.49.14251
[29]	G. Kresse, J. Furthmuller, Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set, Comput. Mater. Sci. 6 (1996) 15-50. doi: 10.1016/0927-0256(96)00008-0
[30]	G. Kresse, J. Furthmuller, Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set, Phys. Rev. B 54 (1996) 11169-11186. doi: 10.1103/PhysRevB.54.11169
[31]	P.E. Blöchl, Projector augmented-wave method, Phys. Rev. B 50 (1994) 17953-17979. doi: 10.1103/PhysRevB.50.17953
[32]	G. Kresse, D. Joubert, From ultrasoft pseudopotentials to the projector augmented-wave method, Phys. Rev. B 59 (1999) 1758-1775.
[33]	J.P. Perdew, K. Burke, M. Ernzerhof, Generalized gradient approximation made simple, Phys. Rev. Lett. 77 (1996) 3865-3868. doi: 10.1103/PhysRevLett.77.3865
[34]	S.L. Dudarev, G.A. Botton, S.Y. Savrasov, C.J. Humphreys, A.P. Sutton, Electron-energy-loss spectra and the structural stability of nickel oxide: an LSDA+U study, Phys. Rev. B 57 (1998) 1505-1509. doi: 10.1103/PhysRevB.57.1505
[35]	A.K. Mishra, A. Roldan, N.H. de Leeuw, CuO Surfaces and CO₂ activation: a dispersion-corrected DFT+U study, J. Phys. Chem. C 120 (2016) 2198-2214.
[36]	B. Walls, A.A. Mazilkin, B.O. Mukhamedov, A. Ionov, I.A. Smirnova, A.V. Ponomareva, K. Fleischer, N.A. Kozlovskaya, D.A. Shulyatev, I.A. Abrikosov, I.V. Shvets, S.I. Bozhko, Nanodomain structure of single crystalline nickel oxide, Sci. Rep. 11 (2021) 3496. doi: 10.1038/s41598-021-82070-1
[37]	S. Grimme, J. Antony, S. Ehrlich, H. Krieg, A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu, J. Chem. Phys. 132 (2010) 154104. doi: 10.1063/1.3382344
[38]	S. Grimme, S. Ehrlich, L. Goerigk, Effect of the damping function in dispersion corrected density functional theory, J. Comput. Chem. 32 (2011) 1456-1465. doi: 10.1002/jcc.21759
[39]	V. Wang, N. Xu, J.C. Liu, G. Tang, W.T. Geng, VASPKIT: a user-friendly interface facilitating high-throughput computing and analysis using VASP code, Comput. Phys. Commun. 267 (2021) 108033. doi: 10.1016/j.cpc.2021.108033
[40]	K. Momma, F. Izumi, VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data, J. Appl. Crystallogr. 44 (2011) 1272-1276. doi: 10.1107/S0021889811038970
[41]	J.P. Perdew, M. Ernzerhof, K. Burke, Rationale for mixing exact exchange with density functional approximations, J. Chem. Phys. 105 (1996) 9982-9985. doi: 10.1063/1.472933
[42]	M. Gerosa, C.E. Bottani, L. Caramella, G. Onida, C. Di Valentin, G. Pacchioni, Electronic structure and phase stability of oxide semiconductors: performance of dielectric-dependent hybrid functional DFT, benchmarked against GW band structure calculations and experiments, Phys. Rev. B 91 (2015) 155201. doi: 10.1103/PhysRevB.91.155201
[43]	A.J. Medford, J. Sehested, J. Rossmeisl, I. Chorkendorff, F. Studt, J.K. Noerskov, P.G. Moses, Thermochemistry and micro-kinetic analysis of methanol synthesis on ZnO (0001), J. Catal. 309 (2014) 397-407. doi: 10.1016/j.jcat.2013.10.015
[44]	S.R. Kelly, X. Shi, S. Back, L. Vallez, S.Y. Park, S. Siahrostami, X. Zheng, J.K. Noerskov, ZnO as an active and selective catalyst for electrochemical water oxidation to hydrogen peroxide, ACS Catal. 9 (2019) 4593-4599. doi: 10.1021/acscatal.8b04873
[45]	S.H. Yoo, M. Todorova, D. Wickramaratne, L. Weston, C.G.V. d. Walle, J. Neugebauer, Finite-size correction for slab supercell calculations of materials with spontaneous polarization, NPJ Comput. Mater. 7 (2021) 58. doi: 10.1038/s41524-021-00529-1
[46]	A.A. Peterson, F. Abild-Pedersen, F. Studt, J. Rossmeisl, J.K. Noerskov, How copper catalyzes the electroreduction of carbon dioxide into hydrocarbon fuels, Energy Environ. Sci. 3 (2010) 1311-1315. doi: 10.1039/c0ee00071j
[47]	J.T. Feaster, C. Shi, E.R. Cave, T. Hatsukade, D.N. Abram, K.P. Kuhl, C. Hahn, J.K. Noerskov, T.F. Jaramillo, Understanding selectivity for the electrochemical reduction of carbon dioxide to formic acid and carbon monoxide on metal electrodes, ACS Catal. 7 (2017) 4822-4827. doi: 10.1021/acscatal.7b00687
[48]	F. Oba, A. Togo, I. Tanaka, J. Paier, G. Kresse, Defect energetics in ZnO: a hybrid Hartree-Fock density functional study, Phys. Rev. B 77 (2008) 245202. doi: 10.1103/PhysRevB.77.245202
[49]	A. Janotti, C.G. Van de Walle, Oxygen vacancies in ZnO, Appl. Phys. Lett. 87 (2005) 122102. doi: 10.1063/1.2053360
[50]	J. Meng, J. Li, J. Liu, X. Zhang, G. Jiang, L. Ma, Z.Y. Hu, S. Xi, Y. Zhao, M. Yan, P. Wang, X. Liu, Q. Li, J.Z. Liu, T. Wu, L. Mai, Universal approach to fabricating graphene-supported single-atom catalysts from doped ZnO solid solutions, ACS Cent. Sci. 6 (2020) 1431-1440. doi: 10.1021/acscentsci.0c00458
[51]	Y.H. Lu, W.H. Lin, C.Y. Yang, Y.H. Chiu, Y.C. Pu, M.H. Lee, Y.C. Tseng, Y.J. Hsu, A facile green antisolvent approach to Cu²⁺-doped ZnO nanocrystals with visible-light-responsive photoactivities, Nanoscale 6 (2014) 8796-8803. doi: 10.1039/C4NR01607F
[52]	Y. Jin, Q. Cui, G. Wen, Q. Wang, J. Hao, S. Wang, J. Zhang, XPS and Raman scattering studies of room temperature ferromagnetic ZnO: Cu, J. Phys. D 42 (2009) 215007. doi: 10.1088/0022-3727/42/21/215007
[53]	A. Zhang, Y. Liang, H. Li, X. Zhao, Y. Chen, B. Zhang, W. Zhu, J. Zeng, Harmonizing the electronic structures of the adsorbate and catalysts for efficient CO₂ reduction, Nano Lett. 19 (2019) 6547-6553. doi: 10.1021/acs.nanolett.9b02782
[54]	M. Li, X. Wang, F. Li, L. Zheng, J. Xu, J. Yu, A bifunctional photo-assisted Li-O₍₂₎ battery based on a hierarchical heterostructured cathode, Adv. Mater. 32 (2020) 1907098. doi: 10.1002/adma.201907098
[55]	K. Jiang, Y. Huang, G. Zeng, F.M. Toma, W.A. Goddard, A.T. Bell, Effects of surface roughness on the electrochemical reduction of CO₂ over Cu, ACS Energy Lett. 5 (2020) 1206-1214. doi: 10.1021/acsenergylett.0c00482
[56]	M. Moradi, F. Hasanvandian, A.A. Isari, F. Hayati, B. Kakavandi, S.R. Setayesh, CuO and ZnO co-anchored on g-C₃N₄ nanosheets as an affordable double Z-scheme nanocomposite for photocatalytic decontamination of amoxicillin, Appl. Catal. B Environ. 285 (2021) 119838. doi: 10.1016/j.apcatb.2020.119838
[57]	M. Lei, N. Wang, L. Zhu, Q. Zhou, G. Nie, H. Tang, Photocatalytic reductive degradation of polybrominated diphenyl ethers on CuO/TiO₂ nanocomposites: a mechanism based on the switching of photocatalytic reduction potential being controlled by the valence state of copper, Appl. Catal. B Environ. 182 (2016) 414-423. doi: 10.1016/j.apcatb.2015.09.031
[58]	W.D. Oh, Z. Wong, X. Chen, K.Y.A. Lin, A. Veksha, G. Lisak, C. He, T.T. Lim, Enhanced activation of peroxydisulfate by CuO decorated on hexagonal boron nitride for bisphenol A removal, Chem. Eng. J. 393 (2020) 124714. doi: 10.1016/j.cej.2020.124714
[59]	Y. Tong, H. Guo, D. Liu, X. Yan, P. Su, J. Liang, S. Zhou, J. Liu, G.Q. Lu, S.X. Dou, Vacancy engineering of iron-doped W₁₈O₄₉ nanoreactors for low-barrier electrochemical nitrogen reduction, Angew. Chem. Int. Ed. 59 (2020) 7356-7361. doi: 10.1002/anie.202002029
[60]	X. Xu, L. Li, J. Huang, H. Jin, X. Fang, W. Liu, N. Zhang, H. Wang, X. Wang, Engineering Ni³⁺ cations in NiO lattice at the atomic level by Li⁺ doping: the roles of Ni³⁺ and oxygen species for CO oxidation, ACS Catal. 8 (2018) 8033-8045. doi: 10.1021/acscatal.8b01692