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Berrissoul A, Dafali A, Benhiba F, Outada H, Warad I, Dikici B, Zarrouk A. Experimental and theoretical insights into Artemisia Stems aqueous extract as a sustainable and eco-friendly corrosion inhibitor for mild steel in 1 M HCl environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:36643-36662. [PMID: 38750274 DOI: 10.1007/s11356-024-33636-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 05/06/2024] [Indexed: 06/20/2024]
Abstract
The present research demonstrates an innovative investigation of environmentally friendly mild steel (M-steel) corrosion inhibition using the artemisia stems aqueous extract (ASAEx) as an inhibitor in hydrochloric acid 1 M. The standard extraction technique of hydrodistillation was used for producing the aqueous solutions of ASAEx. To assess the ratios of the chemical components, phytochemical screening was used to identify the stems of this plant. We used a variety of methods and techniques in our research on corrosion inhibition, including weight loss measures, surface analysis methods like XPS and SEM/EDS, electrochemical testing like PDP and EIS, as well as computational lead compound evaluation. Maximum inhibitory efficacy was achieved with 400 mg/L ASAEx in 1 M HCl at 303 K, i.e. 90%. The PDP investigation verified the mixed-kind inhibitor status of the ASAEx extract. To describe the surface of M-steel, fitting and synthetic data were used to identify a constant phase element (CPE). SEM surface analysis was also used to detect the ASAEx effect on the surface of M-steel. X-ray photoelectron spectroscopy (XPS) analysis shows the presence of trace molecules of ASAEx on M-steel surface characterizing the bands in Maj-ASAEx (major compound of ASAEx). Density functional theory (DFT) and molecular dynamics simulations (MDs) were used in computational chemistry to clarify the adsorption mechanism and inhibitory impact.
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Affiliation(s)
- Asmae Berrissoul
- LCEA Laboratory, Faculty of Sciences, Mohammed First University, Oujda, Morocco
| | - Ali Dafali
- LCEA Laboratory, Faculty of Sciences, Mohammed First University, Oujda, Morocco
| | - Fouad Benhiba
- Higher Institute of Nursing Professions and Health Techniques of Agadir Annex Guelmim, Agadir, Morocco
- Laboratory of Materials, Nanotechnology and Environment, Faculty of Sciences, Mohammed V University in Rabat, P.O. Box. 1014, Rabat, Morocco
| | - Halima Outada
- Operational Research and Applied Statistics Team (ROSA), University Mohammed Premier, 60046, Oujda, Morocco
| | - Ismail Warad
- Department of Chemistry, AN-Najah National University, P.O. Box 7, Nablus, Palestine
| | - Burak Dikici
- Department of Mechanical Engineering, Ataturk University, 25240, Erzurum, Turkey
| | - Abdelkader Zarrouk
- Laboratory of Materials, Nanotechnology and Environment, Faculty of Sciences, Mohammed V University in Rabat, P.O. Box. 1014, Rabat, Morocco.
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Liu Y, Chu S, Xu Y, Chen X, Zhou H, Li J, Ren Y, Su X. Upcycling of Cr-Containing Sulfate Waste into Efficient FeCrO 3/Fe 2O 3 Catalysts for CO 2 Hydrogenation Reaction. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1598. [PMID: 38612111 PMCID: PMC11012381 DOI: 10.3390/ma17071598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/24/2024] [Accepted: 03/29/2024] [Indexed: 04/14/2024]
Abstract
Upcycling Cr-containing sulfate waste into catalysts for CO2 hydrogenation reaction benefits both pollution mitigation and economic sustainability. In this study, FeCrO3/Fe2O3 catalysts were successfully prepared by a simple hydrothermal method using Cr-containing sodium sulfate (Cr-SS) as a Cr source for efficient conversion and stable treatment of Cr. The removal rate of Cr in Cr-SS can reach 99.9% at the optimized hydrothermal conditions. When the synthesized catalysts were activated and used for the CO2 hydrogenation reaction, a 50% increase in CO2 conversion was achieved compared with the catalyst prepared by impregnation with a comparable amount of Cr. According to the extraction and risk assessment code (RAC) of the Reference Office of the European Community Bureau (BCR), the synthesized FeCrO3/Fe2O3 is risk-free. This work not only realizes the detoxification of the Cr-SS but transfers Cr into stable FeCrO3 for application in a catalytic field, which provides a strategy for the harmless disposal and resource utilization of Cr-containing hazardous waste.
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Affiliation(s)
- Yongqi Liu
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Shasha Chu
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yuebing Xu
- School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Xinyu Chen
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Hao Zhou
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Jinlin Li
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yanjie Ren
- Xinjiang Qinghua Energy Group Co., Ltd., Yining County 835100, China
| | - Xintai Su
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
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3
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Silva JPDS, Costa RC, Nagay BE, Borges MHR, Sacramento CM, da Cruz NC, Rangel EC, Fortulan CA, da Silva JHD, Ruiz KGS, Barão VAR. Boosting Titanium Surfaces with Positive Charges: Newly Developed Cationic Coating Combines Anticorrosive and Bactericidal Properties for Implant Application. ACS Biomater Sci Eng 2023; 9:5389-5404. [PMID: 37561763 DOI: 10.1021/acsbiomaterials.3c00491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Along with poor implant-bone integration, peri-implant diseases are the major causes of implant failure. Although such diseases are primarily triggered by biofilm accumulation, a complex inflammatory process in response to corrosive-related metallic ions/debris has also been recognized as a risk factor. In this regard, by boosting the titanium (Ti) surface with silane-based positive charges, cationic coatings have gained increasing attention due to their ability to kill pathogens and may be favorable for corrosion resistance. Nevertheless, the development of a cationic coating that combines such properties in addition to having a favorable topography for implant osseointegration is lacking. Because introducing hydroxyl (-OH) groups to Ti is essential to increase chemical bonds with silane, Ti pretreatment is of utmost importance to achieve such polarization. In this study, plasma electrolytic oxidation (PEO) was investigated as a new route to pretreat Ti with OH groups while providing favorable properties for implant application compared with traditional hydrothermal treatment (HT). To produce bactericidal and corrosion-resistant cationic coatings, after pretreatment with PEO or HT (Step 1), surface silanization was subsequently performed via immersion-based functionalization with 3-aminopropyltriethoxysilane (APTES) (Step 2). In the end, five groups were assessed: untreated Ti (Ti), HT, PEO, HT+APTES, and PEO+APTES. PEO created a porous surface with increased roughness and better mechanical and tribological properties compared with HT and Ti. The introduction of -OH groups by HT and PEO was confirmed by Fourier transform infrared spectroscopy and the increase in wettability producing superhydrophilic surfaces. After silanization, the surfaces were polarized to hydrophobic ones, and an increase in the amine functional group was observed by X-ray photoelectron spectroscopy, demonstrating a considerable amount of positive ions. Such protonation may explain the enhanced corrosion resistance and dead bacteria (Streptococcus aureus and Escherichia coli) found for PEO+APTES. All groups presented noncytotoxic properties with similar blood plasma protein adsorption capacity vs the Ti control. Our findings provide new insights into developing next-generation cationic coatings by suggesting that a tailorable porous and oxide coating produced by PEO has promise in designing enhanced cationic surfaces targeting biomedical and dental implant applications.
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Affiliation(s)
- João Pedro Dos S Silva
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Raphael C Costa
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Bruna E Nagay
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Maria H R Borges
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Catharina M Sacramento
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Nilson C da Cruz
- Laboratory of Technological Plasmas, Institute of Science and Technology, São Paulo State University (UNESP), Av. Três de Março, 511, Sorocaba, São Paulo 18087-180, Brazil
| | - Elidiane C Rangel
- Laboratory of Technological Plasmas, Institute of Science and Technology, São Paulo State University (UNESP), Av. Três de Março, 511, Sorocaba, São Paulo 18087-180, Brazil
| | - Carlos A Fortulan
- Department of Mechanical Engineering, University of São Paulo (USP), Trabalhador São Carlense, 400, São Carlos, São Paulo 13566-590, Brazil
| | - José H D da Silva
- Department of Physics, School of Sciences, São Paulo State University (UNESP), Av. Eng. Luís Edmundo C. Coube, 14-01, Bauru, São Paulo 17033-360, Brazil
| | - Karina G S Ruiz
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
| | - Valentim A R Barão
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil
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Zhang L, Luo Q, Hu S, Hu Z, Zhang W, Yang J. Enhanced Electron-Hole Separation in Phosphorus-Coordinated Co Atom on g-C 3N 4 toward Photocatalytic Overall Water Splitting. J Phys Chem Lett 2022; 13:11961-11967. [PMID: 36534693 DOI: 10.1021/acs.jpclett.2c02663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Revealing the decoration mode of g-C3N4 and understanding the physical mechanism of overall water splitting is important for the further improvement of the photocatalytic activity of g-C3N4-based materials. With core level shift and molecular dynamics simulations based on first-principles calculations, Co1(PHx)3 anchored on the triazine of g-C3N4 is determined as a stable single-atom catalyst with high efficiency for photocatalytic overall water splitting. The separated spin-polarized charge density distribution of valence-band maximum and conduction-band minimum states is beneficial for the long lifetime of photoexcited electrons and holes. An anchored Co single atom site is the active site for oxygen evolution reaction, and nitrogen atoms act as active sites for hydrogen evolution reaction. This new decoration mode of g-C3N4 opens a possible way to functionalize g-C3N4 on both triazine and void sites to realize the separation of OER and hydrogenation reaction by water splitting.
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Affiliation(s)
- Lifu Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, Anhui, China
- School of Physics, Nankai University, Tianjin300071, China
| | - Qiquan Luo
- Institutes of Physical Science and Information Technology, Anhui University, Hefei230607, Anhui, China
| | - Shuanglin Hu
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang621900, Sichuan, China
| | - Zhenpeng Hu
- School of Physics, Nankai University, Tianjin300071, China
| | - Wenhua Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, Anhui, China
- Synergetic Innovation of Quantum Information & Quantum Technology, University of Science and Technology of China, Hefei230026, Anhui, China
| | - Jinlong Yang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei230026, Anhui, China
- Synergetic Innovation of Quantum Information & Quantum Technology, University of Science and Technology of China, Hefei230026, Anhui, China
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5
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Bagus PS, Nelin CJ, Brundle CR, Crist BV, Ilton ES, Lahiri N, Rosso KM. Main and Satellite Features in the Ni 2p XPS of NiO. Inorg Chem 2022; 61:18077-18094. [DOI: 10.1021/acs.inorgchem.2c02549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Paul S. Bagus
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5017, United States
| | | | | | | | - Eugene S. Ilton
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Nabajit Lahiri
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Kevin M. Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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6
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Simple, controllable and environmentally friendly synthesis of FeCoNiCuZn-based high-entropy alloy (HEA) catalysts, and their surface dynamics during nitrobenzene hydrogenation. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.139972] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Matias ML, Pimentel A, Reis-Machado AS, Rodrigues J, Deuermeier J, Fortunato E, Martins R, Nunes D. Enhanced Fe-TiO 2 Solar Photocatalysts on Porous Platforms for Water Purification. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1005. [PMID: 35335818 PMCID: PMC8955547 DOI: 10.3390/nano12061005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 02/04/2023]
Abstract
In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO2) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO2 and Fe-TiO2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV-VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO2 substrate was 1.5-times faster than pure TiO2. Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.
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Affiliation(s)
- Maria Leonor Matias
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
| | - Ana Pimentel
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
| | - Ana S. Reis-Machado
- LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal;
| | - Joana Rodrigues
- Physics Department & I3N, Aveiro University, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal;
| | - Jonas Deuermeier
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
| | - Elvira Fortunato
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
| | - Rodrigo Martins
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
| | - Daniela Nunes
- CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, 2829-516 Caparica, Portugal; (M.L.M.); (A.P.); (J.D.); (E.F.)
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8
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Bagus PS, Nelin CJ, Brundle CR, Crist BV, Lahiri N, Rosso KM. Origin of the complex main and satellite features in Fe 2p XPS of Fe 2O 3. Phys Chem Chem Phys 2022; 24:4562-4575. [PMID: 35129561 DOI: 10.1039/d1cp04886d] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although the origin and assignment of the complex XPS features of the cations in ionic compounds has been the subject of extensive theoretical work, agreement with experimental observations remains insufficient for unambiguous interpretation. This paper presents a rigorous ab initio treatment of the main and satellite features in the Fe 2p XPS of Fe2O3. This has been possible using a unique methodology for the selection of orbitals that are used to form the ionic wavefunctions. This orbital selection makes it possible to treat both the angular momentum coupling of the open shell core and valence electrons as well the shake excitations from the closed shell orbitals associated with the O ligands into the valence open shell orbitals associated with the Fe 3d shell. This allows the character of the ionic states in terms of the occupations of the open shell core and valence orbitals and of the contributions of 2p1/2 and 2p3/2 ionization to the XPS intensities to be determined. Our analysis gives strong evidence that many body effects are essential for a correct description of the ionic states and, in general the states cannot be described by a single configuration over the open shell orbitals. An important consequence is that the Fe 2p XPS intensity in most of the features arises from small contributions from the ionization to many, tens to hundreds, of often unresolved ionic states. While the usual understanding of the lower binding energy main and satellite features as being dominantly from 2p3/2 ionization is confirmed, this is not the case for the higher binding energy features where 2p1/2 and 2p3/2 ionization and shake excitations in the valence space mix strongly. Furthermore, we have been able to show that a very large fraction, 88%, of the total Fe 2p XPS intensity is contained in a relatively small binding energy range of ∼35 eV. This is relevant if one wants to extract the stoichiometry of Fe2O3 from Fe 2p/O 1s intensity ratios. Similar considerations about the importance of many-body effects are likely to be relevant for other ionic compounds as well.
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Affiliation(s)
- Paul S Bagus
- Department of Chemistry, University of North Texas, Denton, TX 76203-5017, USA.
| | | | - C R Brundle
- C. R. Brundle and Associates, Soquel, CA 95073, USA
| | | | - N Lahiri
- Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Kevin M Rosso
- Pacific Northwest National Laboratory, Richland, WA 99352, USA
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Kahk JM, Lischner J. Predicting Core Electron Binding Energies in Elements of the First Transition Series Using the Δ-Self-Consistent-Field Method. Faraday Discuss 2022; 236:364-373. [DOI: 10.1039/d1fd00103e] [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
The Δ-Self-Consistent-Field (ΔSCF) method has been established as an accurate and computationally efficient approach for calculating absolute core electron binding energies for light elements up to chlorine, but relatively little...
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10
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Bagus PS, Schacherl B, Vitova T. Computational and Spectroscopic Tools for the Detection of Bond Covalency in Pu(IV) Materials. Inorg Chem 2021; 60:16090-16102. [PMID: 34634201 PMCID: PMC8564760 DOI: 10.1021/acs.inorgchem.1c01331] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Plutonium is used as a major component of new-generation nuclear fuels and of radioisotope batteries for Mars rovers, but it is also an environmental pollutant. Plutonium clearly has high technological and environmental importance, but it has an extremely complex, not well-understood electronic structure. The level of covalency of the Pu 5f valence orbitals and their role in chemical bonding are still an enigma and thus at the frontier of research in actinide science. We performed fully relativistic quantum chemical computations of the electronic structure of the Pu4+ ion and the PuO2 compound. Using four different theoretical tools, it is shown that the 5f orbitals have very little covalent character although the 5f(7/2) a2u orbital with the highest orbital energy has the greatest extent of covalency in PuO2. It is illustrated that the Pu M4,5 edge high-energy resolution X-ray absorption near-edge structure (Pu M4,5 HR-XANES) spectra cannot be interpreted in terms of dipole selection rules applied between individual 3d and 5f orbitals, but the selection rules must be applied between the total wavefunctions for the initial and excited states. This is because the states cannot be represented by single determinants. They are shown to involve major redistributions on the 5f electrons over the different 5f orbitals. These redistributions could be viewed as shake-up-like excitations in the 5f shell from the lowest orbital energy from J = 5f(5/2) into higher orbital energy J = 5f(7/2). We show that the second peak in the Pu M4 edge and the high-energy shoulder of the Pu M5 edge HR-XANES spectra probe the 5f(7/2) a2u orbital; thus, these spectral features are expected to change upon bond variations. We describe theoretical and spectroscopy tools, which can be applied for all actinide elements in materials with cubic structure.
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Affiliation(s)
- Paul S Bagus
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5017, United States
| | - Bianca Schacherl
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germay
| | - Tonya Vitova
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germay
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11
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Bagus PS, Nelin CJ, Brundle CR, Crist BV, Lahiri N, Rosso KM. Comments on the Theory of Complex XPS Spectra: Extracting Chemical Information from the Fe 3p XPS of Fe Oxides. COMMENT INORG CHEM 2021. [DOI: 10.1080/02603594.2021.1938007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Paul S. Bagus
- Department of Chemistry, University of North Texas, Denton, Texas, USA
| | | | - C. R. Brundle
- C. R. Brundle and Associates, Soquel, California, USA
| | | | - N. Lahiri
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Kevin M. Rosso
- Pacific Northwest National Laboratory, Richland, Washington, USA
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12
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Mandal AK, Jana A, Chowdhury S, Tiwari A, Choudhary RJ, Phase DM. Mixed Mott-Hubbard and charge transfer nature of 4H-SrMnO 3thin film on Si (100). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:235501. [PMID: 33973533 DOI: 10.1088/1361-648x/abe8a3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Accepted: 02/22/2021] [Indexed: 06/12/2023]
Abstract
Room temperature electronic structure of polycrystalline 4H-SrMnO3thin film grown on Si (100) substrate has been studied using resonance photo emission spectroscopy and soft x-ray absorption spectroscopy measurements. Presence of charge transfer screen Mn 3dnLfinal state along with the 3dn-1final state at the valence band edge of 4H-SrMnO3thin film confirms that the ground state is strongly mixed between Mn 3dand O 2pstates. The estimated equivalent values of on-site Coulomb interaction energy (U) and O 2pto Mn 3d- charge transfer energy (Δ) (U≈ Δ ≈ 4.8 eV) from the combination of occupied and unoccupied spectra further confirm the intermediate Mott-Hubbard and charge transfer insulator nature of 4H-SrMnO3film. Despite having similar Mn 4+ valence state in 4H-SrMnO3and cubic SrMnO3, 4H phase is observed to reveal much higher band gap ∼1.5 eV than the cubic phase (0.3 eV), which arises due to different MnO6octahedra environment.
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Affiliation(s)
- Arup Kumar Mandal
- UGC-DAE Consortium for Scientific Research, Indore-452001, Madhya Pradesh, India
| | - Anupam Jana
- UGC-DAE Consortium for Scientific Research, Indore-452001, Madhya Pradesh, India
| | - Sourav Chowdhury
- UGC-DAE Consortium for Scientific Research, Indore-452001, Madhya Pradesh, India
| | - Achyut Tiwari
- Indian Institute of Technology (Indian School of Mines), Dhanbad-826004, Jharkhand, India
| | - R J Choudhary
- UGC-DAE Consortium for Scientific Research, Indore-452001, Madhya Pradesh, India
| | - D M Phase
- UGC-DAE Consortium for Scientific Research, Indore-452001, Madhya Pradesh, India
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13
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Bagus PS, Nelin CJ, Brundle CR, Crist BV, Lahiri N, Rosso KM. Combined multiplet theory and experiment for the Fe 2p and 3p XPS of FeO and Fe 2O 3. J Chem Phys 2021; 154:094709. [PMID: 33685168 DOI: 10.1063/5.0039765] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Al K alpha, 1486.6 eV, based x-ray photoelectron spectroscopy (XPS) of Fe 2p and Fe 3p for Fe(III) in Fe2O3 and Fe(II) in FeO is compared with theoretical predictions based on ab initio wavefunctions that accurately treat the final, core-hole, multiplets. The principal objectives of this comparison are to understand the multiplet structure and to evaluate the use of both the 2p and 3p spectra in determining oxidation states. In order to properly interpret the features of these spectra and to use the XPS to provide atomistic insights as well as atomic composition, it is necessary to understand the origin of the multiplet energies and intensities. The theoretical treatment takes into account the ligand field and spin-orbit splittings, the covalent mixing of ligand and Fe 3d orbitals, and the angular momentum coupling of the open shell electrons. These effects lead to the distribution of XPS intensity into a large number of final, ionic, states that are only partly resolved with energies spread over a wide range of binding energies. For this reason, it is necessary to record the Fe 2p and 3p XPS spectra over a wide energy range, which includes all the multiplets in the theoretical treatment as well as additional shake satellites. We also evaluate the effects of differing assumptions concerning the extrinsic background subtraction, to make sure our experimental spectrum may be fairly compared to the theory. We conclude that the Fe 3p XPS provides an additional means for distinguishing Fe(III) and Fe(II) oxidation states beyond just using the Fe 2p spectrum. In particular, with the use of the Fe 3p XPS, the depth of the material probed is about 1.5 times greater than for the Fe 2p XPS. In addition, a new type of atomic many-body effect that involves excitations into orbitals that have Fe f,ℓ = 3, symmetry has been shown to be important for the Fe 3p XPS.
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Affiliation(s)
- Paul S Bagus
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5017, USA
| | | | - C R Brundle
- C. R. Brundle and Associates, Soquel, California 95073, USA
| | | | - N Lahiri
- Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Kevin M Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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