51
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Hwang J, Rao RR, Giordano L, Katayama Y, Yu Y, Shao-Horn Y. Perovskites in catalysis and electrocatalysis. Science 2018; 358:751-756. [PMID: 29123062 DOI: 10.1126/science.aam7092] [Citation(s) in RCA: 546] [Impact Index Per Article: 91.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Catalysts for chemical and electrochemical reactions underpin many aspects of modern technology and industry, from energy storage and conversion to toxic emissions abatement to chemical and materials synthesis. This role necessitates the design of highly active, stable, yet earth-abundant heterogeneous catalysts. In this Review, we present the perovskite oxide family as a basis for developing such catalysts for (electro)chemical conversions spanning carbon, nitrogen, and oxygen chemistries. A framework for rationalizing activity trends and guiding perovskite oxide catalyst design is described, followed by illustrations of how a robust understanding of perovskite electronic structure provides fundamental insights into activity, stability, and mechanism in oxygen electrocatalysis. We conclude by outlining how these insights open experimental and computational opportunities to expand the compositional and chemical reaction space for next-generation perovskite catalysts.
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Affiliation(s)
- Jonathan Hwang
- Department of Materials Science and Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Reshma R Rao
- Department of Mechanical Engineering, MIT, Cambridge, MA 02139, USA
| | - Livia Giordano
- Department of Mechanical Engineering, MIT, Cambridge, MA 02139, USA.,Department of Material Science, Università di Milano-Bicocca, Via Cozzi 55, 20136 Milano, Italy
| | - Yu Katayama
- Research Laboratory of Electronics, MIT, Cambridge, MA 02139, USA.,Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Yang Yu
- Department of Materials Science and Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Yang Shao-Horn
- Department of Materials Science and Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA. .,Department of Mechanical Engineering, MIT, Cambridge, MA 02139, USA.,Research Laboratory of Electronics, MIT, Cambridge, MA 02139, USA
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52
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van Oversteeg CHM, Doan HQ, de Groot FMF, Cuk T. In situ X-ray absorption spectroscopy of transition metal based water oxidation catalysts. Chem Soc Rev 2018; 46:102-125. [PMID: 27834973 DOI: 10.1039/c6cs00230g] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
X-ray absorption studies of the geometric and electronic structure of primarily heterogeneous Co, Ni, and Mn based water oxidation catalysts are reviewed. The X-ray absorption near edge and extended X-ray absorption fine structure studies of the metal K-edge, characterize the metal oxidation state, metal-oxygen bond distance, metal-metal distance, and degree of disorder of the catalysts. These properties guide the coordination environment of the transition metal oxide radical that localizes surface holes and is required to oxidize water. The catalysts are investigated both as-prepared, in their native state, and under reaction conditions, while transition metal oxide radicals are generated. The findings of many experiments are summarized in tables. The advantages of future X-ray experiments on water oxidation catalysts, which include the limited data available of the oxygen K-edge, metal L-edge, and resonant inelastic X-ray scattering, are discussed.
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Affiliation(s)
| | - Hoang Q Doan
- Department of Chemistry, University of California - Berkeley, 419 Latimer Hall, Berkeley, CA 94720, USA.
| | - Frank M F de Groot
- Department of Chemistry, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Tanja Cuk
- Department of Chemistry, University of California - Berkeley, 419 Latimer Hall, Berkeley, CA 94720, USA.
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53
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Aschaffenburg DJ, Chen X, Cuk T. Faradaic oxygen evolution from SrTiO 3 under nano- and femto-second pulsed light excitation. Chem Commun (Camb) 2018; 53:7254-7257. [PMID: 28660920 DOI: 10.1039/c7cc03061d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
During photocatalytic water oxidation, n-SrTiO3(100) demonstrated near 100% Faradaic efficiency for O2 evolution with nano- (30 ns) and femto- (150 fs) second pulsed laser excitation of the band gap, despite surface rearrangements attributed to the high peak power (300 MW cm-2). Therefore, these results establish a methodology for tracking intermediates of the water oxidation cycle at the n-SrTiO3(100) surface from the picosecond time scales of charge transfer through to the millisecond time scales of O2 evolution.
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Affiliation(s)
- D J Aschaffenburg
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA
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54
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Sanwald KE, Berto TF, Jentys A, Camaioni DM, Gutiérrez OY, Lercher JA. Kinetic Coupling of Water Splitting and Photoreforming on SrTiO3-Based Photocatalysts. ACS Catal 2018. [DOI: 10.1021/acscatal.7b03192] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Kai E. Sanwald
- Department of Chemistry and Catalysis Research Center, TU München, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Tobias F. Berto
- Department of Chemistry and Catalysis Research Center, TU München, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Andreas Jentys
- Department of Chemistry and Catalysis Research Center, TU München, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Donald M. Camaioni
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Oliver Y. Gutiérrez
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Johannes A. Lercher
- Department of Chemistry and Catalysis Research Center, TU München, Lichtenbergstrasse 4, 85747 Garching, Germany
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
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55
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Yamaguchi K, Shoji M, Isobe H, Yamanaka S, Kawakami T, Yamada S, Katouda M, Nakajima T. Theory of chemical bonds in metalloenzymes XXI. Possible mechanisms of water oxidation in oxygen evolving complex of photosystem II. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1428375] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Kizashi Yamaguchi
- Institute for Nanoscience Design, Osaka University, Osaka, Japan
- Handairigaku Techno-Research, Osaka Univeristy, Osaka, Japan
- Riken Advanced Institute for Computational Science (AICS), Hyogo, Japan
| | - Mitsuo Shoji
- Center for Computational Sciences, University of Tsukuba, Ibaraki, Japan
| | - Hiroshi Isobe
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | | | - Takashi Kawakami
- Graduate School of Science, Osaka University, Osaka, Japan
- Riken Advanced Institute for Computational Science (AICS), Hyogo, Japan
| | - Satoru Yamada
- Riken Advanced Institute for Computational Science (AICS), Hyogo, Japan
| | - Michio Katouda
- Riken Advanced Institute for Computational Science (AICS), Hyogo, Japan
| | - Takahito Nakajima
- Riken Advanced Institute for Computational Science (AICS), Hyogo, Japan
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56
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Biswas S, Husek J, Baker LR. Elucidating ultrafast electron dynamics at surfaces using extreme ultraviolet (XUV) reflection–absorption spectroscopy. Chem Commun (Camb) 2018; 54:4216-4230. [DOI: 10.1039/c8cc01745j] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Time-resolved XUV reflection–absorption spectroscopy probes core-to-valence transitions to reveal state-specific electron dynamics at surfaces.
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57
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Ranasinghe CSK, Yamakata A. Structural changes of water molecules during photoelectrochemical water oxidation on TiO2 thin film electrodes. Phys Chem Chem Phys 2018; 20:3388-3394. [DOI: 10.1039/c7cp06646e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hydrogen bonding networks at the water/TiO2 interface were heavily disrupted and an isolated OH band appeared during photoelectrochemical water oxidation.
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Affiliation(s)
| | - Akira Yamakata
- Graduate School of Engineering
- Toyota Technological Institute
- Nagoya 468-8511
- Japan
- Cooperative Research Fellow
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58
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Husek J, Cirri A, Biswas S, Baker LR. Surface electron dynamics in hematite (α-Fe 2O 3): correlation between ultrafast surface electron trapping and small polaron formation. Chem Sci 2017; 8:8170-8178. [PMID: 29619171 PMCID: PMC5861984 DOI: 10.1039/c7sc02826a] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/09/2017] [Indexed: 11/21/2022] Open
Abstract
Spectroscopically following charge carrier dynamics in catalytic materials has proven to be a difficult task due to the ultrafast timescales involved in charge trapping and the lack of spectroscopic tools available to selectively probe surface electronic structure. Transient extreme ultraviolet reflection-absorption (XUV-RA) spectroscopy is able to follow surface electron dynamics due to its element, oxidation-state, and surface specificity, as well as the ultrafast time-resolution which can be achieved with XUV pulses produced by high harmonic generation. Here, we use ultrafast XUV-RA spectroscopy to show that charge localization and small polaron formation in Fe2O3 occur within ∼660 fs. The photoexcitation of hematite at 400 nm initially leads to an electronically-delocalized ligand-to-metal charge transfer (LMCT) state, which subsequently evolves into a surface localized LMCT state. Comparison of the charge carrier dynamics for single and polycrystalline samples shows that the observed dynamics are negligibly influenced by grain boundaries and surface defects. Rather, correlation between experimental results and spectral simulations reveals that the lattice expansion during small polaron formation occurs on the identical time scale as surface trapping and represents the probable driving force for sub-ps electron localization to the hematite surface.
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Affiliation(s)
- Jakub Husek
- The Ohio State University , Columbus , OH 43210 , USA .
| | - Anthony Cirri
- The Ohio State University , Columbus , OH 43210 , USA .
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59
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Migani A, Blancafort L. What Controls Photocatalytic Water Oxidation on Rutile TiO2(110) under Ultra-High-Vacuum Conditions? J Am Chem Soc 2017; 139:11845-11856. [DOI: 10.1021/jacs.7b05121] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Annapaola Migani
- Departament
de Química Biològica i Modelització Molecular, IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
- Catalan
Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Lluís Blancafort
- Institut
de Química Computacional i Catàlisi and Departament
de Química, Universitat de Girona (UDG), C/M. A. Capmany
69, 17003 Girona, Spain
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60
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Oda A, Ohkubo T, Yumura T, Kobayashi H, Kuroda Y. Identification of a Stable Zn II -Oxyl Species Produced in an MFI Zeolite and Its Reversible Reactivity with O 2 at Room Temperature. Angew Chem Int Ed Engl 2017; 56:9715-9718. [PMID: 28608610 DOI: 10.1002/anie.201702570] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Revised: 06/02/2017] [Indexed: 11/10/2022]
Abstract
Although a terminal oxyl species bound to certain metal ions is believed to be the intermediate for various oxidation reactions, such as O-O bond generation in photosystem II (PSII), such systems have not been characterized. Herein, we report a stable ZnII -oxyl species induced by an MFI-type zeolite lattice and its reversible reactivity with O2 at room temperature. Its intriguing characteristics were confirmed by in situ spectroscopic studies in combination with quantum-chemical calculations, namely analyses of the vibronic Franck-Condon progressions and the ESR signal features of both ZnII -oxyl and ZnII -ozonide species formed during this reversible process. Molecular orbital analyses revealed that the reversible reaction between a ZnII -oxyl species and an O2 molecule proceeds via a radical O-O coupling-decoupling mechanism; the unpaired electron of the oxyl species plays a pivotal role in the O-O bond generation process.
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Affiliation(s)
- Akira Oda
- Precursory Research for Embryonic Science and Technology Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan.,Okayama University, 3-1-1 Tsushima, Kita-ku, Okayama, 700-8530, Japan
| | - Takahiro Ohkubo
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima, Kita-ku, Okayama, 700-8530, Japan
| | - Takashi Yumura
- Department of Chemistry and Materials Technology, Kyoto Institute of Technology, Matugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Hisayoshi Kobayashi
- Department of Chemistry and Materials Technology, Kyoto Institute of Technology, Matugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Yasushige Kuroda
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima, Kita-ku, Okayama, 700-8530, Japan
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61
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Oda A, Ohkubo T, Yumura T, Kobayashi H, Kuroda Y. Identification of a Stable Zn
II
–Oxyl Species Produced in an MFI Zeolite and Its Reversible Reactivity with O
2
at Room Temperature. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201702570] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Akira Oda
- Precursory Research for Embryonic Science and Technology Japan Science and Technology Agency 4-1-8 Honcho, Kawaguchi Saitama 332-0012 Japan
- Okayama University 3-1-1 Tsushima, Kita-ku Okayama 700-8530 Japan
| | - Takahiro Ohkubo
- Department of ChemistryGraduate School of Natural Science and TechnologyOkayama University 3-1-1 Tsushima, Kita-ku Okayama 700-8530 Japan
| | - Takashi Yumura
- Department of Chemistry and Materials TechnologyKyoto Institute of Technology Matugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Hisayoshi Kobayashi
- Department of Chemistry and Materials TechnologyKyoto Institute of Technology Matugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Yasushige Kuroda
- Department of ChemistryGraduate School of Natural Science and TechnologyOkayama University 3-1-1 Tsushima, Kita-ku Okayama 700-8530 Japan
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62
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Factors Controlling the Redox Activity of Oxygen in Perovskites: From Theory to Application for Catalytic Reactions. Catalysts 2017. [DOI: 10.3390/catal7050149] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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63
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Litke A, Su Y, Tranca I, Weber T, Hensen EJM, Hofmann JP. Role of Adsorbed Water on Charge Carrier Dynamics in Photoexcited TiO 2. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2017; 121:7514-7524. [PMID: 28413570 PMCID: PMC5388900 DOI: 10.1021/acs.jpcc.7b00472] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 03/13/2017] [Indexed: 05/23/2023]
Abstract
Overall photocatalytic water splitting is one of the most sought after processes for sustainable solar-to-chemical energy conversion. The efficiency of this process strongly depends on charge carrier recombination and interaction with surface adsorbates at different time scales. Here, we investigated how hydration of TiO2 P25 affects dynamics of photogenerated electrons at the millisecond to minute time scale characteristic for chemical reactions. We used rapid scan diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS). The decay of photogenerated electron absorption was substantially slower in the presence of associated water. For hydrated samples, the charge carrier recombination rates followed an Arrhenius-type behavior in the temperature range of 273-423 K; these became temperature-independent when the material was dehydrated at temperatures above 423 K or cooled below 273 K. A DFT+U analysis revealed that hydrogen bonding with adsorbed water stabilizes surface-trapped holes at anatase TiO2(101) facet and lowers the barriers for hole migration. Hence, hole mobility should be higher in the hydrated material than in the dehydrated system. This demonstrates that adsorbed associated water can efficiently stabilize photogenerated charge carriers in nanocrystalline TiO2 and suppress their recombination at the time scale up to minutes.
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64
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Zhang M, Frei H. Water Oxidation Mechanisms of Metal Oxide Catalysts by Vibrational Spectroscopy of Transient Intermediates. Annu Rev Phys Chem 2017; 68:209-231. [PMID: 28226220 DOI: 10.1146/annurev-physchem-052516-050655] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Water oxidation is an essential reaction of an artificial photosystem for solar fuel generation because it provides electrons needed to reduce carbon dioxide or protons to a fuel. Earth-abundant metal oxides are among the most attractive catalytic materials for this reaction because of their robustness and scalability, but their efficiency poses a challenge. Knowledge of catalytic surface intermediates gained by vibrational spectroscopy under reaction conditions plays a key role in uncovering kinetic bottlenecks and provides a basis for catalyst design improvements. Recent dynamic infrared and Raman studies reveal the molecular identity of transient surface intermediates of water oxidation on metal oxides. Combined with ultrafast infrared observations of how charges are delivered to active sites of the metal oxide catalyst and drive the multielectron reaction, spectroscopic advances are poised to play a key role in accelerating progress toward improved catalysts for artificial photosynthesis.
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Affiliation(s)
- Miao Zhang
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720;
| | - Heinz Frei
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720;
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65
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Pavlovic Z, Ranjan C, van Gastel M, Schlögl R. The active site for the water oxidising anodic iridium oxide probed through in situ Raman spectroscopy. Chem Commun (Camb) 2017; 53:12414-12417. [DOI: 10.1039/c7cc05669a] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The structure of anodic iridium oxide (IrOx) under water oxidation was explored using in situ Raman spectroscopy and theoretical calculations.
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Affiliation(s)
- Zoran Pavlovic
- Department of Heterogeneous Catalysis
- Max Planck Institute for Chemical Energy Conversion
- Stiftstrasse 34-36
- Muelheim and Ruhr
- Germany
| | - Chinmoy Ranjan
- Department of Heterogeneous Catalysis
- Max Planck Institute for Chemical Energy Conversion
- Stiftstrasse 34-36
- Muelheim and Ruhr
- Germany
| | - Maurice van Gastel
- Department of Heterogeneous Catalysis
- Max Planck Institute for Chemical Energy Conversion
- Stiftstrasse 34-36
- Muelheim and Ruhr
- Germany
| | - Robert Schlögl
- Department of Heterogeneous Catalysis
- Max Planck Institute for Chemical Energy Conversion
- Stiftstrasse 34-36
- Muelheim and Ruhr
- Germany
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66
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Chen X, Choing SN, Aschaffenburg DJ, Pemmaraju CD, Prendergast D, Cuk T. The Formation Time of Ti–O• and Ti–O•–Ti Radicals at the n-SrTiO3/Aqueous Interface during Photocatalytic Water Oxidation. J Am Chem Soc 2016; 139:1830-1841. [DOI: 10.1021/jacs.6b09550] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xihan Chen
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Stephanie N. Choing
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Daniel J. Aschaffenburg
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | | | | | - Tanja Cuk
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
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67
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Pfeifer V, Jones TE, Velasco Vélez JJ, Arrigo R, Piccinin S, Hävecker M, Knop-Gericke A, Schlögl R. In situ observation of reactive oxygen species forming on oxygen-evolving iridium surfaces. Chem Sci 2016; 8:2143-2149. [PMID: 28507666 PMCID: PMC5407268 DOI: 10.1039/c6sc04622c] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 11/30/2016] [Indexed: 12/24/2022] Open
Abstract
In situ XAS measurements reveal that electron-deficient oxygen species form during OER on IrOx and correlate with catalytic activity.
Water splitting performed in acidic media relies on the exceptional performance of iridium-based materials to catalyze the oxygen evolution reaction (OER). In the present work, we use in situ X-ray photoemission and absorption spectroscopy to resolve the long-standing debate about surface species present in iridium-based catalysts during the OER. We find that the surface of an initially metallic iridium model electrode converts into a mixed-valent, conductive iridium oxide matrix during the OER, which contains OII– and electrophilic OI– species. We observe a positive correlation between the OI– concentration and the evolved oxygen, suggesting that these electrophilic oxygen sites may be involved in catalyzing the OER. We can understand this observation by analogy with photosystem II; their electrophilicity renders the OI– species active in O–O bond formation, i.e. the likely potential- and rate-determining step of the OER. The ability of amorphous iridium oxyhydroxides to easily host such reactive, electrophilic species can explain their superior performance when compared to plain iridium metal or crystalline rutile-type IrO2.
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Affiliation(s)
- Verena Pfeifer
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany . .,Catalysis for Energy , Group EM-GKAT , Helmholtz-Zentrum Berlin für Materialien und Energie GmbH , Elektronenspeicherring BESSY II , Albert-Einstein-Str. 15 , 12489 , Berlin , Germany
| | - Travis E Jones
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany .
| | - Juan J Velasco Vélez
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany . .,Department of Heterogeneous Reactions , Max-Planck-Institut für Chemische Energiekonversion , Stiftstr. 34-36 , 45470 , Mülheim a. d. Ruhr , Germany
| | - Rosa Arrigo
- Diamond Light Source Ltd. , Harwell Science & Innovation Campus , Didcot , Oxfordshire OX 11 0DE , UK .
| | - Simone Piccinin
- Consiglio Nazionale delle Ricerche - Istituto Officina dei Materiali , c/o SISSA , Via Bonomea 265 , Trieste , 34136 , Italy
| | - Michael Hävecker
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany . .,Department of Heterogeneous Reactions , Max-Planck-Institut für Chemische Energiekonversion , Stiftstr. 34-36 , 45470 , Mülheim a. d. Ruhr , Germany
| | - Axel Knop-Gericke
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany .
| | - Robert Schlögl
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 , Berlin , Germany . .,Department of Heterogeneous Reactions , Max-Planck-Institut für Chemische Energiekonversion , Stiftstr. 34-36 , 45470 , Mülheim a. d. Ruhr , Germany
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68
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Kraack JP, Hamm P. Surface-Sensitive and Surface-Specific Ultrafast Two-Dimensional Vibrational Spectroscopy. Chem Rev 2016; 117:10623-10664. [DOI: 10.1021/acs.chemrev.6b00437] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Jan Philip Kraack
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Peter Hamm
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
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69
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Cao Y, Chen S, Li Y, Gao Y, Yang D, Shen YR, Liu WT. Evolution of anatase surface active sites probed by in situ sum-frequency phonon spectroscopy. SCIENCE ADVANCES 2016; 2:e1601162. [PMID: 27704049 PMCID: PMC5045268 DOI: 10.1126/sciadv.1601162] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 08/20/2016] [Indexed: 06/06/2023]
Abstract
Surface active sites of crystals often govern their relevant surface chemistry, yet to monitor them in situ in real atmosphere remains a challenge. Using surface-specific sum-frequency spectroscopy, we identified the surface phonon mode associated with the active sites of undercoordinated titanium ions and conjoint oxygen vacancies, and used it to monitor them on anatase (TiO2) (101) under ambient conditions. In conjunction with theory, we determined related surface structure around the active sites and tracked the evolution of oxygen vacancies under ultraviolet irradiation. We further found that unlike in vacuum, the surface oxygen vacancies, which dominate the surface reactivity, are strongly regulated by ambient gas molecules, including methanol and water, as well as weakly associated species, such as nitrogen and hydrogen. The result revealed a rich interplay between prevailing ambient species and surface reactivity, which can be omnipresent in environmental and catalytic applications of titanium dioxides.
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Affiliation(s)
- Yue Cao
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Shiyou Chen
- Key Laboratory of Polar Materials and Devices (MOE), East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Yadong Li
- Division of Interfacial Water and Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Yi Gao
- Division of Interfacial Water and Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Deheng Yang
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Yuen Ron Shen
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai 200433, China
- Physics Department, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Wei-Tao Liu
- Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures [Ministry of Education (MOE)], Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
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