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Liu H, Lu X, Li M, Zhang L, Pan C, Zhang R, Li J, Xiang W. Structural Incorporation of Manganese into Goethite and Its Enhancement of Pb(II) Adsorption. Environ Sci Technol 2018; 52:4719-4727. [PMID: 29608058 DOI: 10.1021/acs.est.7b05612] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Natural goethite (α-FeOOH) commonly accommodates various metal elements by substituting for Fe, which greatly alters the surface reactivity of goethite. This study discloses the enhancement of Mn-substitution for the Pb2+adsorption capacity of goethite. The incorporated Mn in the synthesized goethite presents as Mn(III) and causes a slight decrease in the a and c of the unit cell parameters and an observable increase in the b direction due to the Jahn-Teller effect of the Mn(III)O6 octahedra. With the Mn content increasing, the particle size decreases gradually, and the surface clearly becomes roughened. The Pb2+ adsorption capacity of goethite is observably enhanced by Mn substitution due to the modified surface complexes. And the increased surface-area-normalized adsorption capacity for Mn-substituted goethite indicated that the enhancement of Pb adsorption is not only attributed to the increase of surface area but also to the change of binding complexes. Extended X-ray absorption fine structure (EXAFS) analysis indicates that the binding structures of Pb2+ on goethite presents as edge-sharing complexes with a regular RPb-Fe = 3.31 Å. In the case of Mn-goethite, Pb2+ is also bound with the Mn surface site on the edge-sharing complex with a larger RPb-Mn = 3.47 Å. The mechanism for enhancing Pb2+ adsorption on Mn-goethite can be interpreted as the preferred Pb2+ binding on the Mn site of Mn-goethite surface. In a summary, the Mn-goethite has great potential for material development in environmental remediation.
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Affiliation(s)
- Huan Liu
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
- Department of Earth and Planetary Sciences , Washington University in St. Louis , 1 Brookings Drive , St. Louis , Missouri 63130 , United States
| | - Xiancai Lu
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
| | - Meng Li
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
| | - Lijuan Zhang
- Chinese Academy of Sciences, Shanghai Institute Applied Physics , Shanghai Synchrotron Radiation Facility , Shanghai 201204 , People's Republic of China
| | - Chao Pan
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 United States
| | - Rui Zhang
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
| | - Juan Li
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
| | - Wanli Xiang
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China
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Schofield PF, Smith AD, Scholl A, Doran A, Covey-crump SJ, Young AT, Ohldag H. Chemical and oxidation-state imaging of mineralogical intergrowths: The application of X-ray photo-emission electron microscopy (XPEEM). Coord Chem Rev 2014; 277-278:31-43. [DOI: 10.1016/j.ccr.2014.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Yang J, Liu J, Dynes JJ, Peak D, Regier T, Wang J, Zhu S, Shi J, Tse JS. Speciation and distribution of copper in a mining soil using multiple synchrotron-based bulk and microscopic techniques. Environ Sci Pollut Res Int 2014; 21:2943-2954. [PMID: 24170498 DOI: 10.1007/s11356-013-2214-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 10/02/2013] [Indexed: 06/02/2023]
Abstract
Molecular-level understanding of soil Cu speciation and distribution assists in management of Cu contamination in mining sites. In this study, one soil sample, collected from a mining site contaminated since 1950s, was characterized complementarily by multiple synchrotron-based bulk and spatially resolved techniques for the speciation and distribution of Cu as well as other related elements (Fe, Ca, Mn, K, Al, and Si). Bulk X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy revealed that soil Cu was predominantly associated with Fe oxides instead of soil organic matter. This agreed with the closest association of Cu to Fe by microscopic X-ray fluorescence (U-XRF) and scanning transmission X-ray microscopy (STXM) nanoanalysis, along with the non-occurrence of photoreduction of soil Cu(II) by quick Cu L3,2-edge XANES spectroscopy (Q-XANES) which often occurs when Cu organic complexes are present. Furthermore, bulk-EXAFS and STXM-coupled Fe L3,2-edge nano-XANES analysis revealed soil Cu adsorbed primarily to Fe(III) oxides by inner-sphere complexation. Additionally, Cu K-edge μ-XANES, L3,2-edge bulk-XANES, and successive Q-XANES results identified the presence of Cu2S rather than radiation-damage artifacts dominant in certain microsites of the mining soil. This study demonstrates the great benefits in use of multiple combined synchrotron-based techniques for comprehensive understanding of Cu speciation in heterogeneous soil matrix, which facilitates our prediction of Cu reactivity and environmental fate in the mining site.
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Affiliation(s)
- Jianjun Yang
- Department of Environmental Engineering, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, People's Republic of China
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Fitting Kourkoutis L, Hotta Y, Susaki T, Hwang HY, Muller DA. Nanometer scale electronic reconstruction at the interface between LaVO3 and LaVO4. Phys Rev Lett 2006; 97:256803. [PMID: 17280379 DOI: 10.1103/physrevlett.97.256803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Indexed: 05/13/2023]
Abstract
Electrons at interfaces, driven to minimize their free energy, are distributed differently than in bulk. This can be dramatic at interfaces involving heterovalent compounds. Here we profile an abrupt interface between V 3d2 LaVO3 and V 3d0 LaVO4 using electron energy loss spectroscopy. Although no bulk phase of LaVOx with a V 3d1 configuration exists, we find a nanometer-wide region of V 3d1 at the LaVO3/LaVO4 interface, rather than a mixture of V 3d0 and V 3d2. The two-dimensional sheet of 3d1 electrons is a prototypical electronic reconstruction at an interface between competing ground states.
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Affiliation(s)
- L Fitting Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
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