1
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Chen Y, Rana R, Zhang Y, Hoffman AS, Huang Z, Yang B, Vila FD, Perez-Aguilar JE, Hong J, Li X, Zeng J, Chi M, Kronawitter CX, Wang H, Bare SR, Kulkarni AR, Gates BC. Dynamic structural evolution of MgO-supported palladium catalysts: from metal to metal oxide nanoparticles to surface then subsurface atomically dispersed cations. Chem Sci 2024; 15:6454-6464. [PMID: 38699272 PMCID: PMC11062082 DOI: 10.1039/d4sc00035h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/21/2024] [Indexed: 05/05/2024] Open
Abstract
Supported noble metal catalysts, ubiquitous in chemical technology, often undergo dynamic transformations between reduced and oxidized states-which influence the metal nuclearities, oxidation states, and catalytic properties. In this investigation, we report the results of in situ X-ray absorption spectroscopy, scanning transmission electron microscopy, and other physical characterization techniques, bolstered by density functional theory, to elucidate the structural transformations of a set of MgO-supported palladium catalysts under oxidative treatment conditions. As the calcination temperature increased, the as-synthesized supported metallic palladium nanoparticles underwent oxidation to form palladium oxides (at approximately 400 °C), which, at approximately 500 °C, were oxidatively fragmented to form mixtures of atomically dispersed palladium cations. The data indicate two distinct types of atomically dispersed species: palladium cations located at MgO steps and those embedded in the first subsurface layer of MgO. The former exhibit significantly higher (>500 times) catalytic activity for ethylene hydrogenation than the latter. The results pave the way for designing highly active and stable supported palladium hydrogenation catalysts with optimized metal utilization.
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Affiliation(s)
- Yizhen Chen
- Department of Chemical Engineering, University of California Davis California 95616 USA
| | - Rachita Rana
- Department of Chemical Engineering, University of California Davis California 95616 USA
| | - Yizhi Zhang
- School of Materials Engineering, Purdue University West Lafayette Indiana 47907 USA
| | - Adam S Hoffman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory Menlo Park California 94025 USA
| | - Zhennan Huang
- Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA
| | - Bo Yang
- School of Materials Engineering, Purdue University West Lafayette Indiana 47907 USA
| | - Fernando D Vila
- Department of Physics, University of Washington Seattle Washington 98195 USA
| | - Jorge E Perez-Aguilar
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory Menlo Park California 94025 USA
| | - Jiyun Hong
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory Menlo Park California 94025 USA
| | - Xu Li
- National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Jie Zeng
- National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Miaofang Chi
- Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA
| | - Coleman X Kronawitter
- Department of Chemical Engineering, University of California Davis California 95616 USA
| | - Haiyan Wang
- School of Materials Engineering, Purdue University West Lafayette Indiana 47907 USA
| | - Simon R Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory Menlo Park California 94025 USA
| | - Ambarish R Kulkarni
- Department of Chemical Engineering, University of California Davis California 95616 USA
| | - Bruce C Gates
- Department of Chemical Engineering, University of California Davis California 95616 USA
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2
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Zhou W, Felvey N, Guo J, Hoffman AS, Bare SR, Kulkarni AR, Runnebaum RC, Kronawitter CX. Reduction of Cofed Carbon Dioxide Modifies the Local Coordination Environment of Zeolite-Supported, Atomically Dispersed Chromium to Promote Ethane Dehydrogenation. J Am Chem Soc 2024; 146:10060-10072. [PMID: 38551239 PMCID: PMC11009955 DOI: 10.1021/jacs.4c00995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/28/2024] [Accepted: 03/01/2024] [Indexed: 04/11/2024]
Abstract
The reduction of CO2 is known to promote increased alkene yields from alkane dehydrogenations when the reactions are cocatalyzed. The mechanism of this promotion is not understood in the context of catalyst active-site environments because CO2 is amphoteric, and even general aspects of the chemistry, including the significance of competing side reactions, differ significantly across catalysts. Atomically dispersed chromium cations stabilized in highly siliceous MFI zeolite are shown here to enable the study of the role of parallel CO2 reduction during ethylene-selective ethane dehydrogenation. Based on infrared spectroscopy and X-ray absorption spectroscopy data interpreted through calculations using density functional theory (DFT), the synthesized catalyst contains atomically dispersed Cr cations stabilized by silanol nests in micropores. Reactor studies show that cofeeding CO2 increases stable ethylene-selective ethane dehydrogenation rates over a wide range of partial pressures. Operando X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) spectra indicate that during reaction at 650 °C the Cr cations maintain a nominal 2+ charge and a total Cr-O coordination number of approximately 2. However, CO2 reduction induces a change, correlated with the CO2 partial pressure, in the population of two distinct Cr-O scattering paths. This indicates that the promotional effect of parallel CO2 reduction can be attributed to a subtle change in Cr-O bond lengths in the local coordination environment of the active site. These insights are made possible by simultaneously fitting multiple EXAFS spectra recorded in different reaction conditions; this novel procedure is expected to be generally applicable for interpreting operando catalysis EXAFS data.
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Affiliation(s)
- Wenqi Zhou
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Noah Felvey
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Jiawei Guo
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Adam S. Hoffman
- Stanford
Synchrotron Radiation Lightsource, SLAC
National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Simon R. Bare
- Stanford
Synchrotron Radiation Lightsource, SLAC
National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Ambarish R. Kulkarni
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Ron C. Runnebaum
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
- Department
of Viticulture & Enology, University
of California, Davis, California 95616, United States
| | - Coleman X. Kronawitter
- Department
of Chemical Engineering, University of California, Davis, California 95616, United States
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3
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Zang W, Lee J, Tieu P, Yan X, Graham GW, Tran IC, Wang P, Christopher P, Pan X. Distribution of Pt single atom coordination environments on anatase TiO 2 supports controls reactivity. Nat Commun 2024; 15:998. [PMID: 38307931 PMCID: PMC10837418 DOI: 10.1038/s41467-024-45367-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 01/18/2024] [Indexed: 02/04/2024] Open
Abstract
Single-atom catalysts (SACs) offer efficient metal utilization and distinct reactivity compared to supported metal nanoparticles. Structure-function relationships for SACs often assume that active sites have uniform coordination environments at particular binding sites on support surfaces. Here, we investigate the distribution of coordination environments of Pt SAs dispersed on shape-controlled anatase TiO2 supports specifically exposing (001) and (101) surfaces. Pt SAs on (101) are found on the surface, consistent with existing structural models, whereas those on (001) are beneath the surface after calcination. Pt SAs under (001) surfaces exhibit lower reactivity for CO oxidation than those on (101) surfaces due to their limited accessibility to gas phase species. Pt SAs deposited on commercial-TiO2 are found both at the surface and in the bulk, posing challenges to structure-function relationship development. This study highlights heterogeneity in SA coordination environments on oxide supports, emphasizing a previously overlooked consideration in the design of SACs.
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Affiliation(s)
- Wenjie Zang
- Department of Materials Science and Engineering, University of California, Irvine, CA, 92697, USA
| | - Jaeha Lee
- Department of Chemical Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Peter Tieu
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - Xingxu Yan
- Department of Materials Science and Engineering, University of California, Irvine, CA, 92697, USA
| | - George W Graham
- Department of Materials Science and Engineering, University of California, Irvine, CA, 92697, USA
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Ich C Tran
- Irvine Materials Research Institute, University of California, Irvine, CA, 92697, USA
| | - Peikui Wang
- Department of Chemistry, University of Sherbrooke, Sherbrooke, QC, J1K 2R1, Canada
| | - Phillip Christopher
- Department of Chemical Engineering, University of California, Santa Barbara, CA, 93106, USA.
| | - Xiaoqing Pan
- Department of Materials Science and Engineering, University of California, Irvine, CA, 92697, USA.
- Irvine Materials Research Institute, University of California, Irvine, CA, 92697, USA.
- Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA.
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4
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Zhang T, Yang X, Jin J, Han X, Fang Y, Zhou X, Li Y, Han A, Wang Y, Liu J. Modulating the Electronic Metal-Support Interactions to Anti-Leaching Pt Single Atoms for Efficient Hydrosilylation. Adv Mater 2024; 36:e2304144. [PMID: 38012963 DOI: 10.1002/adma.202304144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 11/12/2023] [Indexed: 11/29/2023]
Abstract
Modulating the electronic metal-support interaction (EMSI) of the single-atomic sites against leaching via microenvironment regulation is critical to achieving high activity and stability but remains challenging. Herein, this work selectively confines Pt single atoms on CoFe layered double hydroxide (LDH) by three oxygen atoms around cation vacancy (Pt1 /LDHV ) or one oxygen atom at the regular surface (Pt1 /LDH) via cation vacancy engineering. By characterizing the structural evolution of the obtained catalysts before and after vacancy construction and single-atom anchoring, this work demonstrates how the microenvironments modulate the EMSI and the catalytic performance. Theoretical simulations further reveal a significantly enhanced EMSI effect by the three-coordinated Pt1 atoms on cation vacancies in Pt1 /LDHV , which endows a more prominent anti-leaching feature than the one-coordinated ones on the regular surface. As a result, the Pt1 /LDHV catalyst shows exceptional performance in anti-Markovnikov alkene hydrosilylation, with a turnover frequency of 1.3 × 105 h-1 . More importantly, the enhanced EMSI of Pt1 /LDHV effectively prevented the leaching of Pt atom from the catalyst surface and can be recycled at least ten times with only a 3.4% loss of catalytic efficiency with minimal Pt leaching, and reach a high turnover number of 1.0 × 106 .
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Affiliation(s)
- Tianyu Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Xiang Yang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Jing Jin
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
- State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences Institution, Beijing, 100190, China
| | - Xu Han
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yingyan Fang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Xulin Zhou
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yaping Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Aijuan Han
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yu Wang
- Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204, China
| | - Junfeng Liu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
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5
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Ostervold L, Smerigan A, Liu MJ, Filardi LR, Vila FD, Perez-Aguilar JE, Hong J, Tarpeh WA, Hoffman AS, Greenlee LF, Clark EL, Janik MJ, Bare SR. Cation Incorporation into Copper Oxide Lattice at Highly Oxidizing Potentials. ACS Appl Mater Interfaces 2023; 15:47025-47036. [PMID: 37756387 DOI: 10.1021/acsami.3c10296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Electrolyte cations can have significant effects on the kinetics and selectivity of electrocatalytic reactions. We show an atypical mechanism through which electrolyte cations can impact electrocatalyst performance─direct incorporation of the cation into the oxide electrocatalyst lattice. We investigate the transformations of copper electrodes in alkaline electrochemistry through operando X-ray absorption spectroscopy in KOH and Ba(OH)2 electrolytes. In KOH electrolytes, both the near-edge structure and extended fine-structure agree with previous studies; however, the X-ray absorption spectra vary greatly in Ba(OH)2 electrolytes. Through a combination of electronic structure modeling, near-edge simulation, and postreaction characterization, we propose that Ba2+ cations are directly incorporated into the lattice and form an ordered BaCuO2 phase at potentials more oxidizing than 200 mV vs the normal hydrogen electrode (NHE). BaCuO2 formation is followed by further oxidation to a bulk Cu3+-like BaxCuyOz phase at 900 mV vs NHE. Additionally, during reduction in Ba(OH)2 electrolyte, we find both Cu-O bonds and Cu-Ba scattering persist at potentials as low as -400 mV vs NHE. To our knowledge, this is the first evidence for direct oxidative incorporation of an electrolyte cation into the bulk lattice to form a mixed oxide electrode. The oxidative incorporation of electrolyte cations to form mixed oxides could open a new route for the in situ formation of active and selective oxidation electrocatalysts.
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Affiliation(s)
- Lars Ostervold
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Adam Smerigan
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Matthew J Liu
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
| | - Leah R Filardi
- Department of Chemical Engineering, University of California, Davis, Davis, California 95616, United States
| | - Fernando D Vila
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jorge E Perez-Aguilar
- 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
| | - William A Tarpeh
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
| | - Adam S Hoffman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Lauren F Greenlee
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ezra Lee Clark
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Michael J Janik
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Simon R Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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6
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Smerigan A, Biswas S, Vila FD, Hong J, Perez-Aguilar J, Hoffman AS, Greenlee L, Getman RB, Bare SR. Aqueous Structure of Lanthanide-EDTA Coordination Complexes Determined by a Combined DFT/EXAFS Approach. Inorg Chem 2023; 62:14523-14532. [PMID: 37624729 DOI: 10.1021/acs.inorgchem.3c01334] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2023]
Abstract
Sustainable production of rare earth elements (REEs) is critical for technologies needed for climate change mitigation, including wind turbines and electric vehicles. However, separation technologies currently used in REE production have large environmental footprints, necessitating more sustainable strategies. Aqueous, affinity-based separations are examples of such strategies. To make these technologies feasible, it is imperative to connect aqueous ligand structure to ligand selectivity for individual REEs. As a step toward this goal, we analyzed the extended X-ray absorption fine structure (EXAFS) of four lanthanides (La, Ce, Pr, and Nd) complexed by a common REE chelator, ethylenediaminetetraacetic acid (EDTA) to determine the aqueous-phase structure. Reference structures from density functional theory (DFT) were used to help fit the EXAFS spectra. We found that all four Ln-EDTA coordination complexes formed 9-coordinate structures with 6 coordinating atoms from EDTA (4 carboxyl oxygen atoms and 2 nitrogen atoms) and 3 oxygen atoms from water molecules. All EXAFS fits were of high quality (R-factor < 0.02) and showed decreasing average first-shell coordination distance across the series (2.62-2.57 Å from La-Nd), in agreement with DFT (2.65-2.56 Å from La-Nd). The insights determined herein will be useful in the development of ligands for sustainable rare earth elements (REE) separation technologies.
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Affiliation(s)
- Adam Smerigan
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Sayani Biswas
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Fernando D Vila
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiyun Hong
- SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jorge Perez-Aguilar
- SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Adam S Hoffman
- SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Lauren Greenlee
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Rachel B Getman
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Simon R Bare
- SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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7
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Li Z, Lu X, Zhao R, Ji S, Zhang M, Horton JH, Wang Y, Xu Q, Zhu J. A Heterogeneous Single Atom Cobalt Catalyst for Highly Efficient Acceptorless Dehydrogenative Coupling Reactions. Small 2023; 19:e2207941. [PMID: 36759950 DOI: 10.1002/smll.202207941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/29/2023] [Indexed: 05/04/2023]
Abstract
A fundamental understanding of metal active sites in single-atom catalysts (SACs) is important and challenging in the development of high-performance catalyst systems. Here, a highly efficient and straightforward molten-salt-assisted approach is reported to create atomically dispersed cobalt atoms supported over vanadium pentoxide layered material, with each cobalt atom coordinated with four neighboring oxygen atoms. The liquid environment and the strong polarizing force of the molten salt at high temperatures potentially favor the weakening of VO bonding and the formation of CoO bonding on the vanadium oxide surface. This cobalt SAC achieves extraordinary catalytic efficiency in acceptorless dehydrogenative coupling of alcohols with amines to give imines, with more than 99% selectivity under almost 100% conversion within 3 h, along with a high turnover frequency (TOF) of 5882 h-1 , exceeding those of previously reported benchmarking catalysts. Moreover, it delivers excellent recyclability, reaction scalability, and substrate tolerance. Density functional theory (DFT) calculations further confirm that the optimized coordination environment and strong electronic metal-support interaction contribute significantly to the activation of reactants. The findings provide a feasible route to construct SACs at the atomic level for use in organic transformations.
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Affiliation(s)
- Zhijun Li
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Xiaowen Lu
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Rufang Zhao
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, P. R. China
| | - Siqi Ji
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Mingyang Zhang
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - J Hugh Horton
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
- Department of Chemistry, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Yang Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, P. R. China
| | - Qian Xu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, P. R. China
| | - Junfa Zhu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, P. R. China
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8
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Li Z, Ji S, Wang C, Liu H, Leng L, Du L, Gao J, Qiao M, Horton JH, Wang Y. Geometric and Electronic Engineering of Atomically Dispersed Copper-Cobalt Diatomic Sites for Synergistic Promotion of Bifunctional Oxygen Electrocatalysis in Zinc-Air Batteries. Adv Mater 2023:e2300905. [PMID: 37040668 DOI: 10.1002/adma.202300905] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/09/2023] [Indexed: 06/19/2023]
Abstract
The development of rechargeable zinc-air batteries is heavily dependent on bifunctional oxygen electrocatalysts to offer exceptional oxygen reduction/evolution reaction (ORR/OER) activities. However, the design of such electrocatalysts with high activity and durability is challenging. Herein, a strategy is proposed to create an electrocatalyst comprised of copper-cobalt diatomic sites on a highly porous nitrogen-doped carbon matrix (Cu-Co/NC) with abundantly accessible metal sites and optimal geometric and electronic structures. Experimental findings and theoretical calculations demonstrate that the synergistic effect of Cu-Co dual-metal sites with metal-N4 coordination induce asymmetric charge distributions with moderate adsorption/desorption behavior with oxygen intermediates. This electrocatalyst exhibits extraordinary bifunctional oxygen electrocatalytic activities in alkaline media, with a half-wave potential of 0.92 V for ORR and a low overpotential of 335 mV at 10 mA cm-2 for OER. In addition, it demonstrates exceptional ORR activity in acidic (0.85 V) and neutral (0.74 V) media. When applied to a zinc-air battery, it achieves extraordinary operational performance and outstanding durability (510 h), ranking it as one of the most efficient bifunctional electrocatalysts reported to date. This work demonstrates the importance of geometric and electronic engineering of isolated dual-metal sites for boosting bifunctional electrocatalytic activity in electrochemical energy devices.
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Affiliation(s)
- Zhijun Li
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Siqi Ji
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Chun Wang
- Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China
| | - Hongxue Liu
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Leipeng Leng
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Lei Du
- Huangpu Hydrogen Energy Innovation Centre, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, 510006, P. R. China
| | - Jincheng Gao
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Man Qiao
- School of Chemistry and Materials Science, Nanjing University of Information Science and Technology, Nanjing, 210044, P. R. China
| | - J Hugh Horton
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
- Department of Chemistry, Queen's University, Kingston, K7L 3N6, Canada
| | - Yu Wang
- Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, P. R. China
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9
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Abstract
Heterogeneous bimetallic catalysts have broad applications in industrial processes, but achieving a fundamental understanding on the nature of the active sites in bimetallic catalysts at the atomic and molecular level is very challenging due to the structural complexity of the bimetallic catalysts. Comparing the structural features and the catalytic performances of different bimetallic entities will favor the formation of a unified understanding of the structure-reactivity relationships in heterogeneous bimetallic catalysts and thereby facilitate the upgrading of the current bimetallic catalysts. In this review, we will discuss the geometric and electronic structures of three representative types of bimetallic catalysts (bimetallic binuclear sites, bimetallic nanoclusters, and nanoparticles) and then summarize the synthesis methodologies and characterization techniques for different bimetallic entities, with emphasis on the recent progress made in the past decade. The catalytic applications of supported bimetallic binuclear sites, bimetallic nanoclusters, and nanoparticles for a series of important reactions are discussed. Finally, we will discuss the future research directions of catalysis based on supported bimetallic catalysts and, more generally, the prospective developments of heterogeneous catalysis in both fundamental research and practical applications.
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10
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Li Z, Ji S, Xu C, Leng L, Liu H, Horton JH, Du L, Gao J, He C, Qi X, Xu Q, Zhu J. Engineering the Electronic Structure of Single-Atom Iron Sites with Boosted Oxygen Bifunctional Activity for Zinc-Air Batteries. Adv Mater 2023; 35:e2209644. [PMID: 36533780 DOI: 10.1002/adma.202209644] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Rechargeable zinc-air batteries typically require efficient, durable, and inexpensive bifunctional electrocatalysts to support oxygen reduction/evolution reactions (ORR/OER). However, sluggish kinetics and mass transportation challenges must be addressed if the performance of these catalysts is to be enhanced. Herein, a strategy to fabricate a catalyst comprising atomically dispersed iron atoms supported on a mesoporous nitrogen-doped carbon support (Fe SAs/NC) with accessible metal sites and optimized electronic metal-support interactions is developed. Both the experimental results and theoretical calculations reveal that the engineered electronic structures of the metal active sites can regulate the charge distribution of Fe centers to optimize the adsorption/desorption of oxygenated intermediates. The Fe SAs/NC containing Fe1 N4 O1 sites achieves remarkable ORR activity over the entire pH range, with half-wave potentials of 0.93, 0.83, and 0.75 V (vs reversible hydrogen electrode) in alkaline, acidic, and neutral electrolytes, respectively. In addition, it demonstrates a promising low overpotential of 320 mV at 10 mA cm-2 for OER in alkaline conditions. The zinc-air battery assembled with Fe SAs/NC exhibits superior performance than that of Pt/C+RuO2 counterpart in terms of peak power density, specific capacity, and cycling stability. These findings demonstrate the importance of the electronic structure engineering of metal sites in directing catalytic activity.
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Affiliation(s)
- Zhijun Li
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Siqi Ji
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Chang Xu
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Leipeng Leng
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Hongxue Liu
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - J Hugh Horton
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
- Department of Chemistry, Queen's University, Kingston, ON, K7L 3N6, Canada
| | - Lei Du
- Huangpu Hydrogen Energy Innovation Centre, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou, 510006, P. R. China
| | - Jincheng Gao
- Joint International Research Laboratory of Advanced Chemical Catalytic Materials & Surface Science, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, 163318, P. R. China
| | - Cheng He
- State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Xiaoying Qi
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Qian Xu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, P. R. China
| | - Junfa Zhu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, P. R. China
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11
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Mou T, Pillai HS, Wang S, Wan M, Han X, Schweitzer NM, Che F, Xin H. Bridging the complexity gap in computational heterogeneous catalysis with machine learning. Nat Catal 2023; 6:122-136. [DOI: 10.1038/s41929-023-00911-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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12
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Gates BC, Katz A, Liu J. Nested Metal Catalysts: Metal Atoms and Clusters Stabilized by Confinement with Accessibility on Supports. Precision Chemistry 2023; 1:3-13. [PMID: 37025973 PMCID: PMC10069032 DOI: 10.1021/prechem.2c00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/09/2023] [Accepted: 01/28/2023] [Indexed: 02/17/2023]
Abstract
Supported catalysts that are important in technology prominently include atomically dispersed metals and metal clusters. When the metals are noble, they are typically unstable-susceptible to sintering-especially under reducing conditions. Embedding the metals in supports such as organic polymers, metal oxides, and zeolites confers stability on the metals but at the cost of catalytic activity associated with the lack of accessibility of metal bonding sites to reactants. An approach to stabilizing noble metal catalysts while maintaining their accessibility involves anchoring them in molecular-scale nests that are in or on supports. The nests include zeolite pore mouths, zeolite surface cups (half-cages), raft-like islands of oxophilic metals bonded to metal oxide supports, clusters of non-noble metals (e.g., hosting noble metals as single-atom alloys), and nanoscale metal oxide islands that selectively bond to the catalytic metals, isolating them from the support. These examples illustrate a trend toward precision in the synthesis of solid catalysts, and the latter two classes of nested catalysts offer realistic prospects for economical large-scale application.
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Affiliation(s)
- Bruce C. Gates
- Department of Chemical Engineering, University of California, Davis, Davis, California 95616, United States
| | - Alexander Katz
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720, United States
| | - Jingyue Liu
- Department of Physics, Arizona State University, Tempe, Arizona 85287, United States
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13
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Abstract
The potential of operando X-ray techniques for following the structure, fate, and active site of single-atom catalysts (SACs) is highlighted with emphasis on a synergetic approach of both topics. X-ray absorption spectroscopy (XAS) and related X-ray techniques have become fascinating tools to characterize solids and they can be applied to almost all the transition metals deriving information about the symmetry, oxidation state, local coordination, and many more structural and electronic properties. SACs, a newly coined concept, recently gained much attention in the field of heterogeneous catalysis. In this way, one can achieve a minimum use of the metal, theoretically highest efficiency, and the design of only one active site-so-called single site catalysts. While single sites are not easy to characterize especially under operating conditions, XAS as local probe together with complementary methods (infrared spectroscopy, electron microscopy) is ideal in this research area to prove the structure of these sites and the dynamic changes during reaction. In this review, starting from their fundamentals, various techniques related to conventional XAS and X-ray photon in/out techniques applied to single sites are discussed with detailed mechanistic and in situ/operando studies. We systematically summarize the design strategies of SACs and outline their exploration with XAS supported by density functional theory (DFT) calculations and recent machine learning tools.
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Affiliation(s)
- Bidyut Bikash Sarma
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 20, 76131 Karlsruhe, Germany,Institute
of Catalysis Research and Technology, Karlsruhe
Institute of Technology, Hermann-von-Helmholtz Platz 1, Eggenstein-Leopoldshafen, 76344 Karlsruhe, Germany,
| | - Florian Maurer
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 20, 76131 Karlsruhe, Germany
| | - Dmitry E. Doronkin
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 20, 76131 Karlsruhe, Germany,Institute
of Catalysis Research and Technology, Karlsruhe
Institute of Technology, Hermann-von-Helmholtz Platz 1, Eggenstein-Leopoldshafen, 76344 Karlsruhe, Germany
| | - Jan-Dierk Grunwaldt
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 20, 76131 Karlsruhe, Germany,Institute
of Catalysis Research and Technology, Karlsruhe
Institute of Technology, Hermann-von-Helmholtz Platz 1, Eggenstein-Leopoldshafen, 76344 Karlsruhe, Germany,
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14
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Zhang T, Jin J, Chen J, Fang Y, Han X, Chen J, Li Y, Wang Y, Liu J, Wang L. Pinpointing the axial ligand effect on platinum single-atom-catalyst towards efficient alkaline hydrogen evolution reaction. Nat Commun 2022; 13:6875. [PMID: 36371427 PMCID: PMC9653394 DOI: 10.1038/s41467-022-34619-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 10/31/2022] [Indexed: 11/13/2022] Open
Abstract
Developing active single-atom-catalyst (SAC) for alkaline hydrogen evolution reaction (HER) is a promising solution to lower the green hydrogen cost. However, the correlations are not clear between the chemical environments around the active-sites and their desired catalytic activity. Here we study a group of SACs prepared by anchoring platinum atoms on NiFe-layered-double-hydroxide. While maintaining the homogeneity of the Pt-SACs, various axial ligands (−F, −Cl, −Br, −I, −OH) are employed via a facile irradiation-impregnation procedure, enabling us to discover definite chemical-environments/performance correlations. Owing to its high first-electron-affinity, chloride chelated Pt-SAC exhibits optimized bindings with hydrogen and hydroxide, which favor the sluggish water dissociation and further promote the alkaline HER. Specifically, it shows high mass-activity of 30.6 A mgPt−1 and turnover frequency of 30.3 H2 s−1 at 100 mV overpotential, which are significantly higher than those of the state-of-the-art Pt-SACs and commercial Pt/C catalyst. Moreover, high energy efficiency of 80% is obtained for the alkaline water electrolyser assembled using the above catalyst under practical-relevant conditions. Establishing robust structure/performance correlations is critical for the development of single-atom-catalysts with improved activity. Here, the axial ligand on Pt single-atom-catalyst is precisely adjusted and studied, showing that the ligand’s first electron affinity is crucial for the catalysis.
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Rana R, Vila FD, Kulkarni AR, Bare SR. Bridging the Gap between the X-ray Absorption Spectroscopy and the Computational Catalysis Communities in Heterogeneous Catalysis: A Perspective on the Current and Future Research Directions. ACS Catal 2022. [DOI: 10.1021/acscatal.2c03863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rachita Rana
- Department of Chemical Engineering, University of California, Davis, California95616, United States
| | - Fernando D. Vila
- Department of Physics, University of Washington, Seattle, Washington98195, United States
| | - Ambarish R. Kulkarni
- Department of Chemical Engineering, University of California, Davis, California95616, United States
| | - Simon R. Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
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16
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Felvey N, Guo J, Rana R, Xu L, Bare SR, Gates BC, Katz A, Kulkarni AR, Runnebaum RC, Kronawitter CX. Interconversion of Atomically Dispersed Platinum Cations and Platinum Clusters in Zeolite ZSM-5 and Formation of Platinum gem-Dicarbonyls. J Am Chem Soc 2022; 144:13874-13887. [PMID: 35854402 DOI: 10.1021/jacs.2c05386] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Catalysts composed of platinum dispersed on zeolite supports are widely applied in industry, and coking and sintering of platinum during operation under reactive conditions require their oxidative regeneration, with the platinum cycling between clusters and cations. The intermediate platinum species have remained only incompletely understood. Here, we report an experimental and theoretical investigation of the structure, bonding, and local environment of cationic platinum species in zeolite ZSM-5, which are key intermediates in this cycling. Upon exposure of platinum clusters to O2 at 700 °C, oxidative fragmentation occurs, and Pt2+ ions are stabilized at six-membered rings in the zeolite that contain paired aluminum sites. When exposed to CO under mild conditions, these Pt2+ ions form highly uniform platinum gem-dicarbonyls, which can be converted in H2 to Ptδ+ monocarbonyls. This conversion, which weakens the platinum-zeolite bonding, is a first step toward platinum migration and aggregation into clusters. X-ray absorption and infrared spectra provide evidence of the reductive and oxidative transformations in various gas environments. The chemistry is general, as shown by the observation of platinum gem-dicarbonyls in several commercially used zeolites (ZSM-5, Beta, mordenite, and Y).
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Affiliation(s)
- Noah Felvey
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Jiawei Guo
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Rachita Rana
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Le Xu
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Simon R Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, 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
| | - Ambarish R Kulkarni
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Ron C Runnebaum
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Coleman X Kronawitter
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
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17
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Chen Y, Rana R, Huang Z, Vila FD, Sours T, Perez-Aguilar JE, Zhao X, Hong J, Hoffman AS, Li X, Shang C, Blum T, Zeng J, Chi M, Salmeron M, Kronawitter CX, Bare SR, Kulkarni AR, Gates BC. Atomically Dispersed Platinum in Surface and Subsurface Sites on MgO Have Contrasting Catalytic Properties for CO Oxidation. J Phys Chem Lett 2022; 13:3896-3903. [PMID: 35471032 DOI: 10.1021/acs.jpclett.2c00667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Atomically dispersed metals on metal oxide supports are a rapidly growing class of catalysts. Developing an understanding of where and how the metals are bonded to the supports is challenging because support surfaces are heterogeneous, and most reports lack a detailed consideration of these points. Herein, we report two atomically dispersed CO oxidation catalysts having markedly different metal-support interactions: platinum in the first layer of crystalline MgO powder and platinum in the second layer of this support. Structural models have been determined on the basis of data and computations, including those determined by extended X-ray absorption fine structure and X-ray absorption near edge structure spectroscopies, infrared spectroscopy of adsorbed CO, and scanning transmission electron microscopy. The data demonstrate the transformation of surface to subsurface platinum as the temperature of sample calcination increased. Catalyst performance data demonstrate the lower activity but greater stability of the subsurface platinum than of the surface platinum.
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Affiliation(s)
- Yizhen Chen
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Rachita Rana
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Zhennan Huang
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Fernando D Vila
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Tyler Sours
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Jorge E Perez-Aguilar
- 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
| | - Adam S Hoffman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Xu Li
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Chunyan Shang
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Thomas Blum
- University of California Irvine, Irvine, California 92697, United States
| | - Jie Zeng
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Miaofang Chi
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | | | - Coleman X Kronawitter
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Simon R Bare
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Ambarish R Kulkarni
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Bruce C Gates
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
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