1
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Fan Q, Li H, Saqline S, Donat F, Tan M, Tao L, Müller CR, Xu ZJ, Liu W. An investigation of the structural and electronic origins of enhanced chemical looping air separation performance of B-site substituted SrFe 1-xCo xO 3-δ perovskites. Phys Chem Chem Phys 2024. [PMID: 39034776 DOI: 10.1039/d4cp02152e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
Chemical looping air separation (CLAS) is a promising process intensification technology for extracting oxygen from air for oxygen enrichment in process streams. Co-doped strontium ferrites (SrFe1-xCoxO3-δ) have been found to have outstanding activities for CLAS processes. In this study, we explore the underlying factors driving the enhancement in oxygen uptake and release performance of perovskite structured SrFe1-xCoxO3-δ oxygen carriers for CLAS. Phase-pure perovskites, with B site substituted by up to 75 mol% Co, were prepared by a sol-gel method and systematically investigated through a wide range of well controlled experimental and computational approaches. While all SrFe1-xCoxO3-δ oxygen carriers showed excellent cyclic stability and structural reversibility over CLAS cycles, increased B site occupancy by Co resulted in monotonic decrease in onset temperature for oxygen release and increase in oxygen carrying capacity. These experimental trends can be fundamentally explained by an increase in the structural tolerance factor, an elevation in transition metal d-band, as well as an increased degree of hybridization between the metal d-band and the O p band. Therefore, these ab initio structural and electronic descriptors are useful design rationales for the hypothesis-driven synthesis of high-performing oxygen carriers for CLAS.
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Affiliation(s)
- Qianwenhao Fan
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore.
- Cambridge Centre for Advanced Research and Education in Singapore, 1 Create Way, Singapore 138602, Singapore
| | - Haiyan Li
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Syed Saqline
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore.
- Cambridge Centre for Advanced Research and Education in Singapore, 1 Create Way, Singapore 138602, Singapore
- Nanyang Environmental and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Felix Donat
- Department of Mechanical and Process Engineering, ETH Zurich, Leonhardstrasse 21, Zürich 8092, Switzerland
| | - Mingwu Tan
- Institute of Sustainability for Chemicals, Energy and Environment, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - Longgang Tao
- Institute of Sustainability for Chemicals, Energy and Environment, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - Christoph R Müller
- Department of Mechanical and Process Engineering, ETH Zurich, Leonhardstrasse 21, Zürich 8092, Switzerland
| | - Zhichuan J Xu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Wen Liu
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore.
- Cambridge Centre for Advanced Research and Education in Singapore, 1 Create Way, Singapore 138602, Singapore
- Nanyang Environmental and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
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2
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Zhang X, Cheng N, Zhang Y, Tian S, Han L. Pressure-Induced Enhancement in Chemical Looping Reforming of CH 4: A Thermodynamic Analysis with Fe-Based Oxygen Carriers. CHEMSUSCHEM 2024:e202400856. [PMID: 38894517 DOI: 10.1002/cssc.202400856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 06/12/2024] [Accepted: 06/17/2024] [Indexed: 06/21/2024]
Abstract
Chemical looping reforming of methane (CLRM) with Fe-based oxygen carriers is widely acknowledged as an environmentally friendly and cost-effective approach for syngas production, however, sintering-caused deactivate of oxygen carriers at elevated temperatures of above 900 °C is a longstanding issue restricting the development of CLRM. Here, in order to reduce the reaction temperature without compromising the chemical-looping CH4 conversion efficiency, we proposed a novel operation scheme of CLRM by manipulating the reaction pressure to shift the equilibrium of CH4 partial oxidation towards the forward direction based on the Le Chatelier's principle. The results from thermodynamic simulations showed that, at a fixed reaction temperature, the reduction in pressure led to the increase in CH4 conversion, H2 and CO selectivity, as well as carbon deposition rate of all investigated oxygen carriers. The pressure-negative CLRM with Fe3O4, Fe2O3 and MgFe2O4 could reduce the reaction temperature to below 700 °C on the premise of a satisfactory CLRM performance. In a comprehensive consideration of the CLRM performance, energy consumption, and CH4 requirement, NiFe2O4 was the Fe-based OCs best available for pressure-negative CLRM, especially for an excellent syngas yield of 23.08 mmol/gOC. This study offered a new strategy to address sintering-caused deactivation of materials in chemical looping from the reaction thermodynamics point of view.
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Affiliation(s)
- Xizhe Zhang
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing, 100083, P. R. China
| | - Nuo Cheng
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing, 100083, P. R. China
| | - Yuhan Zhang
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing, 100083, P. R. China
| | - Sicong Tian
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing, 100083, P. R. China
| | - Lujia Han
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing, 100083, P. R. China
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3
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Jia T, Hao Y, Hao H, Zeng Z. Ni-doping effects on formation and migration of oxygen vacancies in SrFe 1-xNi xO 3-δ oxygen carriers. RSC Adv 2024; 14:6360-6366. [PMID: 38380244 PMCID: PMC10877318 DOI: 10.1039/d3ra08321g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 02/05/2024] [Indexed: 02/22/2024] Open
Abstract
Ni is a promising B-site doping element capable of improving the oxygen carrier performance of SrFeO3 perovskite. In this work, the effect of Ni doping on the formation and migration of oxygen vacancies in SrFe1-xNixO3-δ (x = 0, 0.0625, 0.125, 0.1875, and 0.25) is investigated using density functional theory calculations. Our results show that the oxygen vacancies formed from Ni-O-Fe chains exhibit lower formation energy (Ef) compared to those from Fe-O-Fe chains in each doping system. Additionally, Ef generally decreases with an increase of Ni content. This Ni-promoted formation of VO is attributed to three factors: weakened Ni-O bonding, the closure of O-2p states to the Fermi level by Ni-O hybridization, and Ni3+ decreasing the positive charges to be compensated by VO formation. Due to these multiple advantages, a modest Ni doping of x = 0.25 can induce a higher PO2 and a lower T comparted to the relatively larger Co doping of x = 0.5, thermodynamically. Kinetically, Ni-doping appears to be a disadvantage as it hinders oxygen migration, due to a higher oxygen migration barrier through SrSrNi compared to the SrSrFe pathway. However, the overall oxygen ion conduction would not be significantly influenced by hopping through a nearby pathway of SrSrFe with a low migration barrier in a system doped with a small amount of Ni. In a word, a small amount of Ni doping has an advantage over Co doping in terms of enhancing the oxygen carrier performance of the parent SrFeO3 system.
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Affiliation(s)
- Ting Jia
- School of Physics, Hangzhou Normal University Hangzhou Zhejiang 311121 China
| | - Yinuo Hao
- School of Physics, Hangzhou Normal University Hangzhou Zhejiang 311121 China
| | - Hua Hao
- School of Physics, Hangzhou Normal University Hangzhou Zhejiang 311121 China
| | - Zhi Zeng
- Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences Hefei 230031 China
- Science Island Branch of Graduate School, University of Science and Technology of China Hefei 230026 China
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4
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Qiao Y, He J, Zhou Y, Wu S, Li X, Jiang G, Jiang G, Demir M, Ma P. Flexible All-Solid-State Asymmetric Supercapacitors Based on PPy-Decorated SrFeO 3-δ Perovskites on Carbon Cloth. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37933868 DOI: 10.1021/acsami.3c10189] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The defective structure and high oxygen vacancy concentration of SrFeO3-δ perovskite enable fast ion-electron transport, but its low conductivity still hinders the high electrochemical performance. Herein, to enhance the conductivity of SrFeO3-δ-based electrodes, polypyrrole-modified SrFeO3-δ perovskite on carbon cloth (PPy@SFO@CC) has been successfully fabricated by electrodeposition of polypyrrole (PPy) on the surface of SFO@CC. The optimal PPy700@SFO@CC electrode exhibits a specific capacitance of 421 F g-1 at 1 A g-1. It was found that the outside PPy layer not only accelerates the electron transport and ion diffusion but also creates more oxygen vacancies in SrFeO3-δ, enhancing the charge storage performance significantly. Moreover, the NiCo2O4@CC//PPy700@SFO@CC device maintains a specific capacitance of 63.6% after 3000 cycles, which is ascribed to the weak adhesion forces between the active materials and carbon cloth. Finally, the all-solid-state flexible supercapacitor NiCo2O4@CC//PPy700@SFO@CC is constructed with PVA-KOH as the solid electrolyte, delivering an energy density of 16.9 W h kg-1 at a power density of 984 W kg-1. The flexible supercapacitor retains 69% of its specific capacitance after 1000 bending and folding times, demonstrating a certain degree of foldability. The present study opens new avenues for perovskite oxide-based flexible all-solid-state supercapacitors.
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Affiliation(s)
- Yin Qiao
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jiahao He
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yang Zhou
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Shibo Wu
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Xiaoyan Li
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Guangming Jiang
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Guohua Jiang
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Muslum Demir
- TUBITAK Marmara Research Center, Material Institute, Gebze 41470, Turkey
- Chemical Engineering, Osmaniye Korkut Ata University, Osmaniye 80000, Turkey
| | - Pianpian Ma
- School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
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5
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Danmo F, Nylund IE, Westermoen A, Marshall KP, Stoian D, Grande T, Glaum J, Selbach SM. Oxidation Kinetics of Nanocrystalline Hexagonal RMn 1-xTi xO 3 (R = Ho, Dy). ACS APPLIED MATERIALS & INTERFACES 2023; 15:42439-42448. [PMID: 37639468 PMCID: PMC10510046 DOI: 10.1021/acsami.3c06020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023]
Abstract
Hexagonal manganites, RMnO3 (R = Sc, Y, Ho-Lu), are potential oxygen storage materials for air separation due to their reversible oxygen storage and release properties. Their outstanding ability to absorb and release oxygen at relatively low temperatures of 250-400 °C holds promise of saving energy compared to current industrial methods. Unfortunately, the low temperature of operation also implies slow kinetics of oxygen exchange in these materials, which would make them inefficient in applications such as chemical looping air separation. Here, we show that the oxidation kinetics of RMnO3 can be improved through Ti4+-doping as well as by increasing the rare earth cation size. The rate of oxygen absorption of nanocrystalline RMn1-xTixO3 (R = Ho, Dy; x = 0, 0.15) was investigated by thermogravimetric analysis, X-ray absorption near-edge structure, and high-temperature X-ray diffraction (HT-XRD) with in situ switching of atmosphere from N2 to O2. The kinetics of oxidation increases for larger R and even more with Ti4+ donor doping, as both induce expansion of the ab-plane, which reduces the electrostatic repulsion between oxygen in the lattice upon oxygen ion migration. Surface exchange rates and activation energies of oxidation were determined from changes in lattice parameters observed through HT-XRD upon in situ switching of atmosphere.
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Affiliation(s)
- Frida
Hemstad Danmo
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Inger-Emma Nylund
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Aamund Westermoen
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Kenneth P. Marshall
- The
Swiss-Norwegian Beamlines (SNBL), European
Synchrotron Radiation Facility, Grenoble 38043, France
| | - Dragos Stoian
- The
Swiss-Norwegian Beamlines (SNBL), European
Synchrotron Radiation Facility, Grenoble 38043, France
| | - Tor Grande
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Julia Glaum
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Sverre M. Selbach
- Department
of Materials Science and Engineering, NTNU
Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
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6
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Harrison ARP, Kwong KY, Zheng Y, Balkrishna A, Dyson A, Marek EJ. Kinetic and Thermodynamic Enhancement of Low-Temperature Oxygen Release from Strontium Ferrite Perovskites Modified with Ag and CeO 2. ENERGY & FUELS : AN AMERICAN CHEMICAL SOCIETY JOURNAL 2023; 37:9487-9499. [PMID: 37435585 PMCID: PMC10331733 DOI: 10.1021/acs.energyfuels.3c01263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/31/2023] [Indexed: 07/13/2023]
Abstract
The redox behavior of the nonstoichiometric perovskite oxide SrFeO3-δ modified with Ag, CeO2, and Ce was assessed for chemical looping air separation (CLAS) via thermogravimetric analysis and by cyclic release and uptake of O2 in a packed bed reactor. The results demonstrated that the addition of ∼15 wt % Ag at the surface of SrFeO3-δ lowers the temperature of oxygen release in N2 by ∼60 °C (i.e., from 370 °C for bare SrFeO3-δ to 310 °C) and more than triples the amount of oxygen released per CLAS cycle at 500 °C. Impregnation of SrFeO3-δ with Ag increased the concentration of oxygen vacancies at equilibrium, lowering (3 - δ) under all investigated oxygen partial pressures. The addition of CeO2 at the surface or into the bulk of SrFeO3-δ resulted in more modest changes, with a decrease in temperature for O2 release of 20-25 °C as compared to SrFeO3-δ and a moderate increase in oxygen yield per reduction cycle. The apparent kinetic parameters for reduction of SrFeO3-δ, with Ag and CeO2 additives, were determined from the CLAS experiments in a packed bed reactor, giving activation energies and pre-exponential factors of Ea,reduction = 66.3 kJ mol-1 and Areduction = 152 mol s-1 m-3 Pa-1 for SrFeO3-δ impregnated with 10.7 wt % CeO2, 75.7 kJ mol-1 and 623 molO2 s-1 m -3 Pa-1 for SrFeO3-δ mixed with 2.5 wt % CeO2 in the bulk, 29.9 kJ mol-1 and 0.88 molO2 s-1 m-3 Pa-1 for Sr0.95Ce0.05FeO3-δ, and 69.0 kJ mol-1 and 278 molO2 s-1 m-3 Pa-1 for SrFeO3-δ impregnated with 12.7 wt % Ag, respectively. Kinetics for reoxidation were much faster and were assessed for two materials with the slowest oxygen uptake, SrFeO3-δ, giving the activation energy Ea,oxidation = 177.1 kJ mol-1 and pre-exponential factor Aoxidation = 3.40 × 1010 molO2 s-1 m-3 Pa-1, and Sr0.95Ce0.05FeO3-δ, giving the activation energy Ea,oxidation = 64.0 kJ mol-1, and pre-exponential factor Aoxidation = 584 molO2 s-1 m-3 Pa-1.
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Affiliation(s)
- Alexander R. P. Harrison
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, U.K.
| | - Kien Y. Kwong
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, U.K.
| | - Yaoyao Zheng
- Department
of Engineering, University of Cambridge, Trumpington Street, CB2 1PZ Cambridge, U.K.
| | - Abhishek Balkrishna
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, U.K.
| | - Alice Dyson
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, U.K.
| | - Ewa J. Marek
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS Cambridge, U.K.
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7
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BaCoO3−δ perovskite-type oxygen carrier for chemical looping air separation, part Ⅰ: Determination of oxygen non-stoichiometry and cyclic stability of oxygen carrier. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Enhanced photocatalytic activity of La and Zr-codoped AgNbO3 for rhodamine B and methylene blue degradation. JOURNAL OF SAUDI CHEMICAL SOCIETY 2022. [DOI: 10.1016/j.jscs.2022.101534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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High M, Patzschke CF, Zheng L, Zeng D, Gavalda-Diaz O, Ding N, Chien KHH, Zhang Z, Wilson GE, Berenov AV, Skinner SJ, Sedransk Campbell KL, Xiao R, Fennell PS, Song Q. Precursor engineering of hydrotalcite-derived redox sorbents for reversible and stable thermochemical oxygen storage. Nat Commun 2022; 13:5109. [PMID: 36042227 PMCID: PMC9427752 DOI: 10.1038/s41467-022-32593-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 08/01/2022] [Indexed: 11/08/2022] Open
Abstract
Chemical looping processes based on multiple-step reduction and oxidation of metal oxides hold great promise for a variety of energy applications, such as CO2 capture and conversion, gas separation, energy storage, and redox catalytic processes. Copper-based mixed oxides are one of the most promising candidate materials with a high oxygen storage capacity. However, the structural deterioration and sintering at high temperatures is one key scientific challenge. Herein, we report a precursor engineering approach to prepare durable copper-based redox sorbents for use in thermochemical looping processes for combustion and gas purification. Calcination of the CuMgAl hydrotalcite precursors formed mixed metal oxides consisting of CuO nanoparticles dispersed in the Mg-Al oxide support which inhibited the formation of copper aluminates during redox cycling. The copper-based redox sorbents demonstrated enhanced reaction rates, stable O2 storage capacity over 500 redox cycles at 900 °C, and efficient gas purification over a broad temperature range. We expect that our materials design strategy has broad implications on synthesis and engineering of mixed metal oxides for a range of thermochemical processes and redox catalytic applications.
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Affiliation(s)
- Michael High
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Clemens F Patzschke
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Liya Zheng
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Dewang Zeng
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
- Key Laboratory of Energy Thermal Conversion and Control (Ministry of Education), School of Energy and Environment, Southeast University, Nanjing, 210096, P.R. China
| | - Oriol Gavalda-Diaz
- Department of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
- Composites Research Group, University of Nottingham, Jubilee Campus, Nottingham, NG7 2GX, UK
| | - Nan Ding
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Ka Ho Horace Chien
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Zili Zhang
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - George E Wilson
- Department of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Andrey V Berenov
- Department of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Stephen J Skinner
- Department of Materials, Imperial College London, Exhibition Road, London, SW7 2AZ, UK
| | - Kyra L Sedransk Campbell
- Department of Chemical and Biological Engineering, The University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Rui Xiao
- Key Laboratory of Energy Thermal Conversion and Control (Ministry of Education), School of Energy and Environment, Southeast University, Nanjing, 210096, P.R. China.
| | - Paul S Fennell
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
| | - Qilei Song
- Department of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
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10
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Fujishiro F, Oshima N, Sakuragi T, Oishi M. Oxygen desorption properties of perovskite-type SrFe1−Co O3−δ: B-site mixing effect on the reduction properties of Fe and Co ions. J SOLID STATE CHEM 2022. [DOI: 10.1016/j.jssc.2022.123254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Iseki T, Tamura S, Saito M, Tanabe T, Motohashi T. Tunable Oxygen Intake/Release Characteristics of Brownmillerite-Type Ca 2AlMnO 5+δ Involving Atomic Defect Formations. ACS APPLIED MATERIALS & INTERFACES 2021; 13:53717-53724. [PMID: 34736323 DOI: 10.1021/acsami.1c13534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The oxygen intake/release characteristics were systematically studied for Ca2AlMnO5+δ samples synthesized under precisely controlled oxygen pressures. Both the oxygen storage capacity (OSC) and operating temperature were systematically lowered as the oxygen pressure in the firing atmosphere increased. Notably, the sample fired under a 1% O2 atmosphere exhibited sufficiently large OSC and superior oxygen intake/release kinetics to the pristine sample synthesized in an anaerobic condition. The high-angle annular dark-field scanning TEM observation revealed that the samples contain defects in their atomic arrangement when fired in oxygen-rich atmospheres. This result indicates that the oxygen intake/release characteristics of Ca2AlMnO5+δ are sensitive to the synthesis condition and widely tunable even without chemical substitutions.
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Affiliation(s)
- Tomohiro Iseki
- Department of Materials and Life Chemistry, Faculty of Engineering, Kanagawa University, Kanagawa 221-8686, Japan
| | - Sayaka Tamura
- Department of Materials and Life Chemistry, Faculty of Engineering, Kanagawa University, Kanagawa 221-8686, Japan
- Department of Applied Chemistry, School of Science and Technology, Meiji University, Kanagawa 214-8571, Japan
| | - Miwa Saito
- Department of Materials and Life Chemistry, Faculty of Engineering, Kanagawa University, Kanagawa 221-8686, Japan
| | - Toyokazu Tanabe
- Department of Materials Science and Engineering, National Defense Academy, Kanagawa 239-8686, Japan
| | - Teruki Motohashi
- Department of Materials and Life Chemistry, Faculty of Engineering, Kanagawa University, Kanagawa 221-8686, Japan
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12
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Nguyen NP, Farr TP, Bush HE, Ambrosini A, Loutzenhiser PG. Air separation via two-step solar thermochemical cycles based on SrFeO 3-δ and (Ba,La) 0.15Sr 0.85FeO 3-δ perovskite reduction/oxidation reactions to produce N 2: rate limiting mechanism(s) determination. Phys Chem Chem Phys 2021; 23:19280-19288. [PMID: 34525147 DOI: 10.1039/d1cp03303d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two-step solar thermochemical cycles based on reversible reactions of SrFeO3-δ and (Ba,La)0.15Sr0.85FeO3-δ perovskites were considered for air separation. The cycle steps encompass (1) the thermal reduction of SrFeO3-δ or (Ba,La)0.15Sr0.85FeO3-δ perovskites driven by concentrated solar irradiation and (2) oxidation in air to remove O2 and produce N2. Rate limiting mechanisms were examined for both reactions using a combination of isothermal and non-isothermal thermogravimetry for temperature-swings between 673 and 1373 K, heating rates of 10, 20, and 50 K min-1, and O2 pressure-swings between 20% O2/Ar and 100% Ar at atmospheric pressure. Evolved O2 and associated lag due to transport behavior were measured with gas chromatography and used with measured sample temperatures to predict equilibrium compositions from a compound energy formalism thermodynamic model. Measured and predicted chemical equilibrium changes in deviation from stoichiometry were compared. Rapid chemical kinetics were observed as the samples equilibrated rapidly for all conditions, indicative that heat and mass transfer were the rate limiting mechanisms. The effects of bulk diffusion (or gas diffusion through the bed or pellet) were examined using pelletized and loose powdered samples and determined to have no discernable impact.
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Affiliation(s)
- Nhu Pailes Nguyen
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332-0405, USA.
| | - Tyler P Farr
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332-0405, USA.
| | - H Evan Bush
- Concentrating Solar Technologies, Sandia National Laboratories, P.O. Box 5800 MS0734, Albuquerque, NM 87185, USA
| | - Andrea Ambrosini
- Concentrating Solar Technologies, Sandia National Laboratories, P.O. Box 5800 MS0734, Albuquerque, NM 87185, USA
| | - Peter G Loutzenhiser
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332-0405, USA.
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13
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Wexler RB, Gautam GS, Stechel EB, Carter EA. Factors Governing Oxygen Vacancy Formation in Oxide Perovskites. J Am Chem Soc 2021; 143:13212-13227. [PMID: 34428909 DOI: 10.1021/jacs.1c05570] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The control of oxygen vacancy (VO) formation is critical to advancing multiple metal-oxide-perovskite-based technologies. We report the construction of a compact linear model for the neutral VO formation energy in ABO3 perovskites that reproduces, with reasonable fidelity, Hubbard-U-corrected density functional theory calculations based on the state-of-the-art, strongly constrained and appropriately normed exchange-correlation functional. We obtain a mean absolute error of 0.45 eV for perovskites stable at 298 K, an accuracy that holds across a large, electronically diverse set of ABO3 perovskites. Our model considers perovskites containing alkaline-earth metals (Ca, Sr, and Ba) and lanthanides (La and Ce) on the A-site and 3d transition metals (Ti, V, Cr, Mn, Fe, Co, and Ni) on the B-site in six different crystal systems (cubic, tetragonal, orthorhombic, hexagonal, rhombohedral, and monoclinic) common to perovskites. Physically intuitive metrics easily extracted from existing experimental thermochemical data or via inexpensive quantum mechanical calculations, including crystal bond dissociation energies and (solid phase) reduction potentials, are key components of the model. Beyond validation of the model against known experimental trends in materials used in solid oxide fuel cells, the model yields new candidate perovskites not contained in our training data set, such as (Bi,Y)(Fe,Co)O3, which we predict may have favorable thermochemical water-splitting properties. The confluence of sufficient accuracy, efficiency, and interpretability afforded by our model not only facilitates high-throughput computational screening for any application that requires the precise control of VO concentrations but also provides a clear picture of the dominant physics governing VO formation in metal-oxide perovskites.
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Affiliation(s)
- Robert B Wexler
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544-5263, United States
| | - Gopalakrishnan Sai Gautam
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544-5263, United States
| | - Ellen B Stechel
- ASU LightWorks and the School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287-5402, United States
| | - Emily A Carter
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544-5263, United States.,Office of the Chancellor and Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
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14
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Shen K, Paige JM, Kwon O, Gorte RJ, Vohs JM. Thermodynamic Properties of Iron Oxide Thin-Film Oxygen Carriers Prepared by Atomic Layer Deposition. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c01907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Kai Shen
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Julian M. Paige
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Ohhun Kwon
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Raymond J. Gorte
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - John M. Vohs
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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Popczun EJ, Jia T, Natesakhawat S, Marin CM, Nguyen-Phan TD, Duan Y, Lekse JW. Investigation of Sr 0.7 Ca 0.3 FeO 3 Oxygen Carriers with Variable Cobalt B-Site Substitution. CHEMSUSCHEM 2021; 14:1893-1901. [PMID: 33508157 DOI: 10.1002/cssc.202002849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/27/2021] [Indexed: 06/12/2023]
Abstract
A-site and B-site substitutions are effective methods towards improving well-studied oxygen carrier materials that are vital for emerging gasification technologies. Such materials include SrFeO3 , which greatly benefits from the inclusion of calcium and/or cobalt, and Sr0.8 Ca0.2 Fe0.4 Co0.6 O3 has been regarded as the best-performing composition. In this study, systems with higher calcium and lower cobalt contents are investigated with a view to lessening the societal and economic burdens of these dual-doped carriers. Density functional theory calculations are performed to illustrate the Fe-O bonding and relaxation contributions to the oxygen vacancy formation energy in Sr1-x Cax Fe1-y Coy O3 systems (x=0.1875, 0.25, 0.3125; y=0.125, 0.25, 0.375, 0.5) and determine that increased calcium A-site substitution requires the use of less cobalt B-site doping to reach the same oxygen vacancy formation. These findings are experimentally validated in situ and ex situ characterization of bulk Sr0.7 Ca0.3 Fe1-y Coy O3 materials. Sr0.7 Ca0.3 Fe0.7 Co0.3 O3 is found to have similar O2 adsorption/desorption rates and storage capacity to Sr0.8 Ca0.2 Fe0.4 Co0.6 O3 in air/N2 cycling experiments. Additionally, both materials are outperformed by Sr0.7 Ca0.3 Fe1-y Coy O3 systems with y=0-0.10 at 400-500 °C, which cycle 1.5 wt% O2 in under ten minutes.
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Affiliation(s)
- Eric J Popczun
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
- Leidos Research Support Team, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Ting Jia
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Sittichai Natesakhawat
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
- Leidos Research Support Team, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Chris M Marin
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
- Leidos Research Support Team, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Thuy-Duong Nguyen-Phan
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
- Leidos Research Support Team, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Yuhua Duan
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
| | - Jonathan W Lekse
- National Energy Technology Laboratory, United States Department of Energy, Pittsburgh, Pennsylvania 15236-0940, USA
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16
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Zhu X, Gao Y, Wang X, Haribal V, Liu J, Neal LM, Bao Z, Wu Z, Wang H, Li F. A tailored multi-functional catalyst for ultra-efficient styrene production under a cyclic redox scheme. Nat Commun 2021; 12:1329. [PMID: 33637739 PMCID: PMC7910546 DOI: 10.1038/s41467-021-21374-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/25/2021] [Indexed: 01/31/2023] Open
Abstract
Styrene is an important commodity chemical that is highly energy and CO2 intensive to produce. We report a redox oxidative dehydrogenation (redox-ODH) strategy to efficiently produce styrene. Facilitated by a multifunctional (Ca/Mn)1-xO@KFeO2 core-shell redox catalyst which acts as (i) a heterogeneous catalyst, (ii) an oxygen separation agent, and (iii) a selective hydrogen combustion material, redox-ODH auto-thermally converts ethylbenzene to styrene with up to 97% single-pass conversion and >94% selectivity. This represents a 72% yield increase compared to commercial dehydrogenation on a relative basis, leading to 82% energy savings and 79% CO2 emission reduction. The redox catalyst is composed of a catalytically active KFeO2 shell and a (Ca/Mn)1-xO core for reversible lattice oxygen storage and donation. The lattice oxygen donation from (Ca/Mn)1-xO sacrificially stabilizes Fe3+ in the shell to maintain high catalytic activity and coke resistance. From a practical standpoint, the redox catalyst exhibits excellent long-term performance under industrially compatible conditions.
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Affiliation(s)
- Xing Zhu
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China
| | - Yunfei Gao
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Xijun Wang
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Vasudev Haribal
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Junchen Liu
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Luke M Neal
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA
| | - Zhenghong Bao
- Oak Ridge National Laboratory, Chemical Science Division and Center for Nanophase Materials Sciences, Oak Ridge, TN, USA
| | - Zili Wu
- Oak Ridge National Laboratory, Chemical Science Division and Center for Nanophase Materials Sciences, Oak Ridge, TN, USA
| | - Hua Wang
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China
| | - Fanxing Li
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA.
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Jin F, Xu C, Yu H, Xia X, Ye F, Li X, Du X, Yang Y. CaCo 0.05Mn 0.95O 3-δ: A Promising Perovskite Solid Solution for Solar Thermochemical Energy Storage. ACS APPLIED MATERIALS & INTERFACES 2021; 13:3856-3866. [PMID: 33430584 DOI: 10.1021/acsami.0c18207] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The redox cycle of doped CaMnO3-δ has emerged as an attractive way for cost-effective thermochemical energy storage (TCES) at high temperatures in concentrating solar power. The role of dopants is mainly to improve the thermal stability of CaMnO3-δ at high temperatures and the overall TCES density of the material. Herein, Co-doped CaMnO3-δ (CaCoxMn1-xO3-δ, x = 0-0.5) perovskites have been proposed as a promising candidate for TCES materials for the first time. The phase compositions, redox capacities, TCES densities, reaction rates, and redox chemistry of the samples have been explored via experimental analysis and theoretical calculations. The results demonstrate that CaCo0.05Mn0.95O3-δ showed an enhanced redox capacity (1000 °C at pO2 = 10-5 bar) without decomposition and provided the highest TCES density of ∼571 kJ kg-1 reported so far. The effective Co doping tended to increase the valence states of B-site cations in perovskite and facilitate the diffusion of the lattice oxygen atoms into the surface-active oxygen sites. Furthermore, the high cooling rates deteriorated the microstructure of CaCo0.05Mn0.95O3-δ particles and resulted in incomplete heat release, which is instructive to the design and operation of the TCES systems.
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Affiliation(s)
- Fei Jin
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
- School of Chemistry and Chemical Engineering, Ningxia Key Laboratory of Solar Chemical Conversion Technology, State Ethnic Affairs Commission, North Minzu University, Yinchuan 750021, P. R. China
| | - Chao Xu
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
| | - Hangyu Yu
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
| | - Xin Xia
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
| | - Feng Ye
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
| | - Xin Li
- Key Laboratory of Solar Thermal Energy and Photovoltaic System, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Xiaoze Du
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
| | - Yongping Yang
- Key Laboratory of Power Station Energy Transfer Conversion and System of MOE, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, P. R. China
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18
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Liu W. Controlling lattice oxygen activity of oxygen carrier materials by design: a review and perspective. REACT CHEM ENG 2021. [DOI: 10.1039/d1re00209k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The lattice oxygen activity of oxygen carriers is critical to chemical looping processes and can be effectively controlled with prepared (i) solid solution mixtures, (ii) ternary oxide phases or (iii) core–shell structured oxygen carriers.
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Affiliation(s)
- Wen Liu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
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19
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An A- and B-Site Substitutional Study of SrFeO 3-δ Perovskites for Solar Thermochemical Air Separation. MATERIALS 2020; 13:ma13225123. [PMID: 33202894 PMCID: PMC7698150 DOI: 10.3390/ma13225123] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 11/22/2022]
Abstract
An A‑ and B‑site substitutional study of SrFeO3−δ perovskites (A’xA1−xB’yB1−yO3−δ, where A = Sr and B = Fe) was performed for a two‑step solar thermochemical air separation cycle. The cycle steps encompass (1) the thermal reduction of A’xSr1−xB’yFe1−yO3−δ driven by concentrated solar irradiation and (2) the oxidation of A’xSr1−xB’yFe1−yO3−δ in air to remove O2, leaving N2. The oxidized A’xSr1−xB’yFe1−yO3−δ is recycled back to the first step to complete the cycle, resulting in the separation of N2 from air and concentrated solar irradiation. A-site substitution fractions between 0 ≤ x ≤ 0.2 were examined for A’ = Ba, Ca, and La. B-site substitution fractions between 0 ≤ y ≤ 0.2 were examined for B’ = Cr, Cu, Co, and Mn. Samples were prepared with a modified Pechini method and characterized with X-ray diffractometry. The mass changes and deviations from stoichiometry were evaluated with thermogravimetry in three screenings with temperature- and O2 pressure-swings between 573 and 1473 K and 20% O2/Ar and 100% Ar at 1 bar, respectively. A’ = Ba or La and B’ = Co resulted in the most improved redox capacities amongst temperature- and O2 pressure-swing experiments.
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20
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Luongo G, Donat F, Müller CR. Structural and thermodynamic study of Ca A- or Co B-site substituted SrFeO 3-δ perovskites for low temperature chemical looping applications. Phys Chem Chem Phys 2020; 22:9272-9282. [PMID: 32307485 DOI: 10.1039/d0cp01049a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Perovskite-structured materials, owing to their chemical-physical properties and tuneable composition, have extended their range of applications to chemical looping processes, in which lattice oxygen provides the oxygen needed for chemical reactions omitting the use of co-fed gaseous oxidants. To optimise their oxygen donating behaviour to the specific application a fundamental understanding of the reduction/oxidation characteristics of perovskite structured oxides and their manipulation through the introduction of dopants is key. In this study, we investigate the structural and oxygen desorption/sorption properties of Sr1-xCaxFeO3-δ and SrFe1-xCoxO3-δ (0 ≤ x ≤ 1) to guide the design of more effective oxygen carriers for chemical looping applications at low temperatures (i.e. 400-600 °C). Ca A- or Co B-site substituted SrFeO3-δ show an increased reducibility, resulting in a higher oxygen capacity at T ≤ 600 °C when compared to the unsubstituted sample. The quantitative assessment of the thermodynamic properties (partial molar enthalpy and entropy of vacancy formation) confirms a reduced enthalpy of vacancy formation upon substitution in this temperature range (i.e. 400-600 °C). Among the examined samples, Sr0.8Ca0.2FeO3-δ exhibited the highest oxygen storage capacity (2.15 wt%) at 500 °C, complemented by excellent redox and structural stability over 100 cycles. The thermodynamic assessment, supported by in situ XRD measurements, revealed that the oxygen release occurs with a phase transition perovskite-brownmillerite below 770 °C, while the perovskite structure remains stable above 770 °C.
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Affiliation(s)
- Giancarlo Luongo
- Department of Mechanical and Process Engineering, ETH Zürich, 8092, Zürich, Switzerland.
| | - Felix Donat
- Department of Mechanical and Process Engineering, ETH Zürich, 8092, Zürich, Switzerland.
| | - Christoph R Müller
- Department of Mechanical and Process Engineering, ETH Zürich, 8092, Zürich, Switzerland.
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21
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Hashimoto K, Otomo R, Kamiya Y. SrFe1−xSnxO3−δ nanoparticles with enhanced redox properties for catalytic combustion of benzene. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01154a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of SrFe1−xSnxO3−δ showed high catalytic activity for benzene combustion. The partial substitution of Fe with Sn increased specific surface area and accelerated redox rates of Fe, resulting in the improvement of the catalytic activity.
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Affiliation(s)
- Kazutaka Hashimoto
- Graduate School of Environmental Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Ryoichi Otomo
- Faculty of Environmental Earth Science
- Hokkaido University
- Sapporo 060-0810
- Japan
| | - Yuichi Kamiya
- Faculty of Environmental Earth Science
- Hokkaido University
- Sapporo 060-0810
- Japan
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