1
|
Palermo AP, Zhang S, Okrut A, Schöttle C, Grosso-Giordano NA, Runnebaum RC, Edwards KC, Guan E, Ertler D, Solovyov A, Kistler JD, Aydin C, Lu J, Busygin I, Dixon DA, Gates BC, Katz A. Remotely Bonded Bridging Dioxygen Ligands Enhance Hydrogen Transfer in a Silica-Supported Tetrairidium Cluster Catalyst. J Am Chem Soc 2024; 146:3773-3784. [PMID: 38301281 DOI: 10.1021/jacs.3c10660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
A longstanding challenge in catalysis by noble metals has been to understand the origin of enhancements of rates of hydrogen transfer that result from the bonding of oxygen near metal sites. We investigated structurally well-defined catalysts consisting of supported tetrairidium carbonyl clusters with single-atom (apical iridium) catalytic sites for ethylene hydrogenation. Reaction of the clusters with ethylene and H2 followed by O2 led to the onset of catalytic activity as a terminal CO ligand at each apical Ir atom was removed and bridging dioxygen ligands replaced CO ligands at neighboring (basal-plane) sites. The presence of the dioxygen ligands caused a 6-fold increase in the catalytic reaction rate, which is explained by the electron-withdrawing capability induced by the bridging dioxygen ligands, consistent with the inference that reductive elimination is rate-determining. Electronic-structure calculations demonstrate an additional role of the dioxygen ligands, changing the mechanism of hydrogen transfer from one involving equatorial hydride ligands to that involving bridging hydride ligands. This mechanism is made evident by an inverse kinetic isotope effect observed in ethylene hydrogenation reactions with H2 and, alternatively, with D2 on the cluster incorporating the dioxygen ligands and is a consequence of quasi-equilibrated hydrogen transfer in this catalyst. The same mechanism accounts for rate enhancements induced by the bridging dioxygen ligands for the catalytic reaction of H2 with D2 to give HD. We posit that the mechanism involving bridging hydride ligands facilitated by oxygen ligands remote from the catalytic site may have some generality in catalysis by oxide-supported noble metals.
Collapse
Affiliation(s)
- Andrew P Palermo
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Shengjie Zhang
- Department of Chemistry & Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Alexander Okrut
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Christian Schöttle
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Nicolás A Grosso-Giordano
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Ron C Runnebaum
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Kyle C Edwards
- Department of Chemistry & Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Erjia Guan
- Department of Materials Science and Engineering, University of California, Davis, California 95616, United States
| | - Daniel Ertler
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Andrew Solovyov
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Joseph D Kistler
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Ceren Aydin
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Jing Lu
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Igor Busygin
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - David A Dixon
- Department of Chemistry & Biochemistry, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Bruce C Gates
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Alexander Katz
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| |
Collapse
|
2
|
Puntscher L, Sombut P, Wang C, Ulreich M, Pavelec J, Rafsanjani-Abbasi A, Meier M, Lagin A, Setvin M, Diebold U, Franchini C, Schmid M, Parkinson GS. A Multitechnique Study of C 2H 4 Adsorption on Fe 3O 4(001). THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2023; 127:18378-18388. [PMID: 37752903 PMCID: PMC10518864 DOI: 10.1021/acs.jpcc.3c03684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/12/2023] [Indexed: 09/28/2023]
Abstract
The adsorption/desorption of ethene (C2H4), also commonly known as ethylene, on Fe3O4(001) was studied under ultrahigh vacuum conditions using temperature-programmed desorption (TPD), scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory (DFT)-based computations. To interpret the TPD data, we have employed a new analysis method based on equilibrium thermodynamics. C2H4 adsorbs intact at all coverages and interacts most strongly with surface defects such as antiphase domain boundaries and Fe adatoms. On the regular surface, C2H4 binds atop surface Fe sites up to a coverage of 2 molecules per (√2 × √2)R45° unit cell, with every second Fe occupied. A desorption energy of 0.36 eV is determined by analysis of the TPD spectra at this coverage, which is approximately 0.1-0.2 eV lower than the value calculated by DFT + U with van der Waals corrections. Additional molecules are accommodated in between the Fe rows. These are stabilized by attractive interactions with the molecules adsorbed at Fe sites. The total capacity of the surface for C2H4 adsorption is found to be close to 4 molecules per (√2 × √2)R45° unit cell.
Collapse
Affiliation(s)
- Lena Puntscher
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | | | - Chunlei Wang
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | - Manuel Ulreich
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | - Jiri Pavelec
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | | | - Matthias Meier
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
- Faculty
of Physics, Center for Computational Materials Science, University of Vienna, Vienna 1090, Austria
| | - Adam Lagin
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | - Martin Setvin
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
- Department
of Surface and Plasma Science, Faculty of
Mathematics and Physics, Charles University, Prague 180 00, Czech Republic
| | - Ulrike Diebold
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | - Cesare Franchini
- Faculty
of Physics, Center for Computational Materials Science, University of Vienna, Vienna 1090, Austria
- Dipartimento
di Fisica e Astronomia, Università
di Bologna, Bologna 40126, Italy
| | - Michael Schmid
- Institute
of Applied Physics, TU Wien, Vienna 1040, Austria
| | | |
Collapse
|
3
|
Chen J, Li H, Wang H, Song Y, Hong Q, Chang K, Hu H, Zhang S, Cao L, Wang C. Phosphine-based metal-organic layers to construct single-site heterogeneous catalysts for arene borylation. Chem Commun (Camb) 2023. [PMID: 37335223 DOI: 10.1039/d3cc01858j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
Metal-organic layers (MOLs) are versatile platforms for creating single-site heterogeneous catalysts. Incorporating molecular functionalities into MOLs is crucial for catalysis. In this study, we synthesized phosphine-containing MOLs constructed from Hf6-oxo secondary building units (SBUs) and phosphine ligands. The mono(phosphine)-Ir complexes generated by the metalation of TPP-MOL were highly active as heterogeneous catalysts for the C(sp2)-H borylation of a range of arenes. This research expands the diversity of MOL-based catalysts.
Collapse
Affiliation(s)
- Jiawei Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Han Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Haoshang Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Yuhang Song
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Qiming Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Kuan Chang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Huihui Hu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Shuhong Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
| | - Lingyun Cao
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, P. R. China
| | - Cheng Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, P. R. China
| |
Collapse
|
4
|
Chen L, Allec SI, Nguyen MT, Kovarik L, Hoffman AS, Hong J, Meira D, Shi H, Bare SR, Glezakou VA, Rousseau R, Szanyi J. Dynamic Evolution of Palladium Single Atoms on Anatase Titania Support Determines the Reverse Water-Gas Shift Activity. J Am Chem Soc 2023; 145:10847-10860. [PMID: 37145876 DOI: 10.1021/jacs.3c02326] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Research interest in single-atom catalysts (SACs) has been continuously increasing. However, the lack of understanding of the dynamic behaviors of SACs during applications hinders catalyst development and mechanistic understanding. Herein, we report on the evolution of active sites over Pd/TiO2-anatase SAC (Pd1/TiO2) in the reverse water-gas shift (rWGS) reaction. Combining kinetics, in situ characterization, and theory, we show that at T ≥ 350 °C, the reduction of TiO2 by H2 alters the coordination environment of Pd, creating Pd sites with partially cleaved Pd-O interfacial bonds and a unique electronic structure that exhibit high intrinsic rWGS activity through the carboxyl pathway. The activation by H2 is accompanied by the partial sintering of single Pd atoms (Pd1) into disordered, flat, ∼1 nm diameter clusters (Pdn). The highly active Pd sites in the new coordination environment under H2 are eliminated by oxidation, which, when performed at a high temperature, also redisperses Pdn and facilitates the reduction of TiO2. In contrast, Pd1 sinters into crystalline, ∼5 nm particles (PdNP) during CO treatment, deactivating Pd1/TiO2. During the rWGS reaction, the two Pd evolution pathways coexist. The activation by H2 dominates, leading to the increasing rate with time-on-stream, and steady-state Pd active sites similar to the ones formed under H2. This work demonstrates how the coordination environment and nuclearity of metal sites on a SAC evolve during catalysis and pretreatments and how their activity is modulated by these behaviors. These insights on SAC dynamics and the structure-function relationship are valuable to mechanistic understanding and catalyst design.
Collapse
Affiliation(s)
- Linxiao Chen
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Sarah I Allec
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Manh-Thuong Nguyen
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Libor Kovarik
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Adam S Hoffman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jiyun Hong
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Debora Meira
- Canadian Light Source Inc., 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - Honghong Shi
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Simon R Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | | | - Roger Rousseau
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - János Szanyi
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| |
Collapse
|
5
|
Jing W, Shen H, Qin R, Wu Q, Liu K, Zheng N. Surface and Interface Coordination Chemistry Learned from Model Heterogeneous Metal Nanocatalysts: From Atomically Dispersed Catalysts to Atomically Precise Clusters. Chem Rev 2022; 123:5948-6002. [PMID: 36574336 DOI: 10.1021/acs.chemrev.2c00569] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The surface and interface coordination structures of heterogeneous metal catalysts are crucial to their catalytic performance. However, the complicated surface and interface structures of heterogeneous catalysts make it challenging to identify the molecular-level structure of their active sites and thus precisely control their performance. To address this challenge, atomically dispersed metal catalysts (ADMCs) and ligand-protected atomically precise metal clusters (APMCs) have been emerging as two important classes of model heterogeneous catalysts in recent years, helping to build bridge between homogeneous and heterogeneous catalysis. This review illustrates how the surface and interface coordination chemistry of these two types of model catalysts determines the catalytic performance from multiple dimensions. The section of ADMCs starts with the local coordination structure of metal sites at the metal-support interface, and then focuses on the effects of coordinating atoms, including their basicity and hardness/softness. Studies are also summarized to discuss the cooperativity achieved by dual metal sites and remote effects. In the section of APMCs, the roles of surface ligands and supports in determining the catalytic activity, selectivity, and stability of APMCs are illustrated. Finally, some personal perspectives on the further development of surface coordination and interface chemistry for model heterogeneous metal catalysts are presented.
Collapse
Affiliation(s)
- Wentong Jing
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Hui Shen
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Ruixuan Qin
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Qingyuan Wu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361102, China
| | - Kunlong Liu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Nanfeng Zheng
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and National & Local Joint Engineering Research Center for Preparation Technology of Nanomaterials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361102, China
| |
Collapse
|
6
|
Awoke YA, Tsai MC, Adam DB, Ayele AA, Yang SC, Huang WH, Chen JL, Pao CW, Mou CY, Su WN, Hwang BJ. The synergistic effect Pt1-W dual sites as a highly active and durable catalyst for electrochemical methanol oxidation. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
7
|
Lin X, Ng SF, Ong WJ. Coordinating single-atom catalysts on two-dimensional nanomaterials: A paradigm towards bolstered photocatalytic energy conversion. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
8
|
Chen L, Kovarik L, Meira D, Szanyi J. Differentiating and Understanding the Effects of Bulk and Surface Mo Doping on CO 2 Hydrogenation over Pd/Anatase-TiO 2. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Linxiao Chen
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Libor Kovarik
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Debora Meira
- CLS@APS Sector 20, Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, United States
- Canadian Light Source Inc., 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada
| | - János Szanyi
- Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| |
Collapse
|
9
|
Liu H, Li Y, Djitcheu X, Liu L. Recent advances in single-atom catalysts for thermally driven reactions. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.117654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
10
|
Di Liberto G, Cipriano LA, Pacchioni G. Role of Dihydride and Dihydrogen Complexes in Hydrogen Evolution Reaction on Single-Atom Catalysts. J Am Chem Soc 2021; 143:20431-20441. [PMID: 34821146 PMCID: PMC8662730 DOI: 10.1021/jacs.1c10470] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Indexed: 11/30/2022]
Abstract
The hydrogen evolution reaction (HER) has a key role in electrochemical water splitting. Recently a lot of attention has been dedicated to HER from single atom catalysts (SACs). The activity of SACs in HER is usually rationalized or predicted using the original model proposed by Nørskov where the free energy of a H atom adsorbed on an extended metal surface M (formation of an MH intermediate) is used to explain the trends in the exchange current for HER. However, SACs differ substantially from metal surfaces and can be considered analogues of coordination compounds. In coordination chemistry, at variance with metal surfaces, stable dihydride or dihydrogen complexes (HMH) can form. We show that the same can occur on SACs and that the formation of stable HMH intermediates, in addition to the MH one, may change the kinetics of the process. Extending the original kinetic model to the case of two intermediates (MH and HMH), one obtains a three-dimensional volcano plot for the HER on SACs. DFT numerical simulations on 55 models demonstrate that the new kinetic model may lead to completely different conclusions about the activity of SACs in HER. The results are validated against selected experimental cases. The work provides an example of the important analogies between the chemistry of SACs and that of coordination compounds.
Collapse
Affiliation(s)
| | - Luis A. Cipriano
- Dipartimento di Scienza dei
Materiali, Università di Milano-Bicocca, Via R. Cozzi 55, 20125 Milano, Italy
| | | |
Collapse
|
11
|
Chen L, Unocic RR, Hoffman AS, Hong J, Braga AH, Bao Z, Bare SR, Szanyi J. Unlocking the Catalytic Potential of TiO 2-Supported Pt Single Atoms for the Reverse Water-Gas Shift Reaction by Altering Their Chemical Environment. JACS AU 2021; 1:977-986. [PMID: 34467344 PMCID: PMC8395703 DOI: 10.1021/jacsau.1c00111] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Indexed: 05/05/2023]
Abstract
Single-atom catalysts (SACs) often exhibit dynamic responses to the reaction and pretreatment environment that affect their activity. The lack of understanding of these behaviors hinders the development of effective, stable SACs, and makes their investigations rather difficult. Here we report a reduction-oxidation cycle that induces nearly 5-fold activity enhancement on Pt/TiO2 SACs for the reverse water-gas shift (rWGS) reaction. We combine microscopy (STEM) and spectroscopy (XAS and IR) studies with kinetic measurements, to convincingly show that the low activity on the fresh SAC is a result of limited accessibility of Pt single atoms (Pt1) due to high Pt-O coordination. The reduction step mobilizes Pt1, forming small, amorphous, and unstable Pt aggregates. The reoxidation step redisperses Pt into Pt1, but in a new, less O-coordinated chemical environment that makes the single metal atoms more accessible and, consequently, more active. After the cycle, the SAC exhibits superior rWGS activity to nonatomically dispersed Pt/TiO2. During the rWGS, the activated Pt1 experience slow deactivation, but can be reactivated by mild oxidation. This work demonstrates a clear picture of how the structural evolution of Pt/TiO2 SACs leads to ultimate catalytic efficiency, offering desired understanding on the rarely explored dynamic chemical environment of supported single metal atoms and its catalytic consequences.
Collapse
Affiliation(s)
- Linxiao Chen
- Institute
for Integrated Catalysis, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
| | - Raymond R. Unocic
- Center
for Nanophase Materials Science, Oak Ridge
National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Adam S. Hoffman
- Stanford
Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jiyun Hong
- Stanford
Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Adriano H. Braga
- Institute
of Chemistry, University of São Paulo, São Paulo, São
Paulo 05508-000, Brazil
| | - Zhenghong Bao
- Chemical
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Simon R. Bare
- Stanford
Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Janos Szanyi
- Institute
for Integrated Catalysis, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
| |
Collapse
|