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Sayago-Carro R, Barba-Nieto I, Caudillo-Flores U, Tolosana-Moranchel Á, Rodríguez JA, Fernández-García M, Kubacka A. Role of Atomicity and Interface on InO x-TiO 2 Composites: Thermo-Photo Valorization of CO 2. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 38888106 DOI: 10.1021/acsami.4c04803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
The synthesis, physicochemical, and functional properties of composite solids resulting from the surface spread of oxidized indium species onto nanoplatelets of anatase were investigated. Both the size and the interaction between the indium- and titanium-containing components control the functional properties. In the reduction of CO2 to CO, the best samples have an indium content between ca. 2 and 5 mol % and showed an excess rate over the photo and thermo-alone processes above 33% and an energy efficiency of 1.3%. Subnanometric (monomeric and dimeric) indium species present relatively weak thermal catalytic response but strong thermo-photo promotion of the activity. A gradual change in functional properties was observed with the growth of the indium content of the solids, leading to a progressive increase of thermal activity but lower thermo-photo promotion. The study provides a well-defined structure-activity relationship rationalizing the dual thermo-photo properties of the catalysts and establishes a guide for the development of highly active and stable composite solids for the elimination and valorization of CO2.
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Affiliation(s)
- Rocío Sayago-Carro
- Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Madrid 28049, Spain
| | - Irene Barba-Nieto
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Uriel Caudillo-Flores
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Ensenada 22800, México
| | | | - José A Rodríguez
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, United States
| | | | - Anna Kubacka
- Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Madrid 28049, Spain
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He S, Niu Y, Xing L, Liang Z, Song X, Ding M, Huang W. Research progress of the detection and analysis methods of heavy metals in plants. FRONTIERS IN PLANT SCIENCE 2024; 15:1310328. [PMID: 38362447 PMCID: PMC10867983 DOI: 10.3389/fpls.2024.1310328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 01/15/2024] [Indexed: 02/17/2024]
Abstract
Heavy metal (HM)-induced stress can lead to the enrichment of HMs in plants thereby threatening people's lives and health via the food chain. For this reason, there is an urgent need for some reliable and practical techniques to detect and analyze the absorption, distribution, accumulation, chemical form, and transport of HMs in plants for reducing or regulating HM content. Not only does it help to explore the mechanism of plant HM response, but it also holds significant importance for cultivating plants with low levels of HMs. Even though this field has garnered significant attention recently, only minority researchers have systematically summarized the different methods of analysis. This paper outlines the detection and analysis techniques applied in recent years for determining HM concentration in plants, such as inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS), X-ray absorption spectroscopy (XAS), X-ray fluorescence spectrometry (XRF), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), non-invasive micro-test technology (NMT) and omics and molecular biology approaches. They can detect the chemical forms, spatial distribution, uptake and transport of HMs in plants. For this paper, the principles behind these techniques are clarified, their advantages and disadvantages are highlighted, their applications are explored, and guidance for selecting the appropriate methods to study HMs in plants is provided for later research. It is also expected to promote the innovation and development of HM-detection technologies and offer ideas for future research concerning HM accumulation in plants.
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Affiliation(s)
- Shuang He
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yuting Niu
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xianyang, China
| | - Lu Xing
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xianyang, China
| | - Zongsuo Liang
- College of Life Sciences and Medicine, Key Laboratory of Plant Secondary Metabolism and Regulation in Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xiaomei Song
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xianyang, China
- Key Laboratory of “Taibaiqiyao” Research and Applications, Shaanxi University of Chinese Medicine, Xianyang, China
| | - Meihai Ding
- Management Department, Xi’an Ande Pharmaceutical Co; Ltd., Xi’an, China
| | - Wenli Huang
- College of Pharmacy, Shaanxi University of Chinese Medicine, Xianyang, China
- Key Laboratory of “Taibaiqiyao” Research and Applications, Shaanxi University of Chinese Medicine, Xianyang, China
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3
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Nurdini N, Ilmi MM, Maryanti E, Setiawan P, Kadja GTM, Ismunandar. Thermally-induced color transformation of hematite: insight into the prehistoric natural pigment preparation. Heliyon 2022; 8:e10377. [PMID: 36061008 PMCID: PMC9433683 DOI: 10.1016/j.heliyon.2022.e10377] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/31/2022] [Accepted: 08/16/2022] [Indexed: 10/31/2022] Open
Abstract
Since the prehistoric era, hematite has been known as a reddish color pigment on rock art, body paint, and decorating substances for objects discovered almost worldwide. Recently, studies about purple hematite used in prehistoric pigment have been done vigorously to investigate the origin of the purple pigment itself. These previous studies indicate that the differentiation of crystallinity, crystal size, morphology, and electronic structure can cause the color shift, resulting in purple hematite. In this study, we conducted a detailed study of the sintering temperature effects on the formation of hematite minerals. This study aims to reveal the structural, crystallography, and electronic transformation in hematite due to heating treatment at various temperatures. The hematite was synthesized using precipitation to imitate the primary method of hematite formation in nature. The sintering process was carried out with temperature variations from 600 °C to 1100 °C and then characterized by crystallographic and structural properties (XRD, Raman Spectroscopy, FTIR), particle size (TEM), as well as electronic properties (DRS, XANES). The crystallinity and particle size of hematite tend to increase along with higher sintering temperatures. Moreover, we noted that the octahedral distortion underwent an intensification with the increase in sintering temperature, which affected the electronic structure of hematite. Specifically, the 1s → 3d transition exhibited lower energy for hematite produced at a higher temperature. This induced a shift in the absorbed energy of the polychromatic light that led to a color shift within hematite, from red to purple. Our finding emphasizes the importance of electronic structure in explaining hematite pigment’s color change rather than relying on simple reasons, such as particle size and crystallinity. In addition, this might strengthen the hypothesis that the prehistoric human created a purple hematite pigment through heating.
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Huang Z, Suzuki H, Ito M, Noguchi S. Direct detection of the crystal form of an active pharmaceutical ingredient in tablets by X-ray absorption fine structure spectroscopy. Int J Pharm 2022; 625:122057. [PMID: 35908632 DOI: 10.1016/j.ijpharm.2022.122057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 07/08/2022] [Accepted: 07/23/2022] [Indexed: 10/16/2022]
Abstract
Different crystal forms of active pharmaceutical ingredients (APIs) may display variations in physicochemical properties. During the drug development process, the definitive purpose is to maintain homogeneous quality in a single crystalline form. Hence, it is important to evaluate and understand the properties of each crystal form of APIs in pharmaceutics. In this study, forms 0, Ⅰ, Ⅱ, III of bromhexine hydrochloride, and form S of bromhexine were characterized by the commonly used methods X-ray powder diffraction, thermogravimetry-differential thermal analysis, and single crystal structure X-ray diffraction. Additionally, X-ray absorption fine structure spectroscopy (XAFS), a seldom used method in the pharmaceutics discipline was also applied to explore the chemical environment of bromine atoms in forms 0, Ⅰ, Ⅱ and S as well as chloride ions in forms 0 to Ⅱ. The XAFS spectra of each form were different from each of the other forms which indicated the chemical environment around target elements in the crystal polymorphs were distinct. Then, we measured the commercial bromhexine hydrochloride tablets with XAFS measurement and found that XAFS could distinguish the crystal form in the tablets. Hence, we demonstrated that XAFS measurements would be applicable as one of the methods for the direct detection of APIs in the tablets.
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Affiliation(s)
- Zhenni Huang
- Graduate School of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8514, Japan
| | - Hironori Suzuki
- Graduate School of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8514, Japan.
| | - Masataka Ito
- Graduate School of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8514, Japan
| | - Shuji Noguchi
- Graduate School of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8514, Japan
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Cheng W, Su H, Liu Q. Tracking the Oxygen Dynamics of Solid-Liquid Electrochemical Interfaces by Correlative In Situ Synchrotron Spectroscopies. Acc Chem Res 2022; 55:1949-1959. [PMID: 35801353 DOI: 10.1021/acs.accounts.2c00239] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
ConspectusOxygen-involved electrocatalytic processes, including the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), are central to a series of advanced modern energy and conversion technologies, such as water electrolyzers, fuel cells, and CO2 reduction or N2 fixation devices. A comprehensive and in-depth understanding of the charge transfer and energy conversion process that ubiquitously occurs over solid-liquid electrochemical interfaces during oxygen electrocatalysis is crucial for understanding the key essence of oxygen-related electrochemistry. The huge challenges for dynamic studies over solid-liquid interfaces during oxygen electrocatalysis lie in the all-embracing electrochemical processes of the catalytic reactions, associated with both structural and reactive intermediates evolution on the electrode surface, and in the significant influence of the aqueous environments of electrolytes used. Hence, overcoming these challenges intrinsically calls for a great cooperation of multiple cutting-edge in situ technologies. Synchrotron radiation (SR) X-ray absorption fine structure (SR-XAFS) spectroscopy is highly sensitive to the local atomic structure of nanomaterials, and SR-based Fourier transform infrared (SR-FTIR) spectroscopy features unique molecular fingerprint identification to determine active species on the surface of electrodes. One can imagine that the correlative in situ SR-XAFS/FTIR spectroscopic investigations will potentially provide sufficient, reliable, and complementary information at the atomic/molecular level to depict vivid and comprehensive "dynamic movies" of solid-liquid electrochemical interfaces during oxygen electrocatalysis, which will help effectively promote/simplify the complicated screening process of advanced oxygen electrocatalysts for efficient high-energy-density energy systems.In this Account, starting with some fundamentals of SR-based spectroscopic technologies, tips for obtaining high-quality SR-XAFS and SR-FTIR spectroscopy results during the electrocatalytic process are comprehensively specified. Subsequently, the latest research achievements of dynamic investigations mainly from our group based on in situ SR-XAFS and/or SR-FTIR spectroscopies will be systematically scrutinized and properly emphasized in detail, where the currently attractive metal-organic-framework (MOF) nanomaterials and single-atom catalysts (SACs) are selected as the main object of research. Moreover, the vital contributions of correlative in situ SR-XAFS/FTIR studies on new discoveries of the dynamic evolution of solid-liquid interfaces during oxygen electrocatalysis are highlighted. In particular, our pioneering research found that the potential-dependent dynamically coupled oxygen formed in the precatalytic stage was a very useful promoter in SACs to promote efficient OER kinetics under acidic conditions. In addition, the in situ generated metastable Ni1-N2 centers with more structural degrees of freedom in SACs could potentially facilitate the fast 4e- ORR kinetics. This Account is anticipated to stimulate broad interest in dynamic explorations in various catalytic processes of interest in the material science and electrochemistry communities using correlative SR-based technologies.
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Affiliation(s)
- Weiren Cheng
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, Anhui, P. R. China.,Institute for Catalysis, Hokkaido University, Sapporo 001-0021, Japan
| | - Hui Su
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, Anhui, P. R. China
| | - Qinghua Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, Anhui, P. R. China
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6
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Oxygen Vacancy-Dependent Chemiluminescence: A Facile Approach for Quantifying Oxygen Defects in ZnO. Anal Chem 2022; 94:8642-8650. [PMID: 35679593 DOI: 10.1021/acs.analchem.2c00359] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Defect engineering is an effective strategy to improve the catalytic activity of metal oxides, and quantitative characterization of surface defects is thus vital to the understanding and application of metal oxide catalysts. Herein, we found that ZnO nanoparticles with oxygen vacancy could trigger the luminol-H2O2 system to emit a strong chemiluminescence (CL), and the CL intensity was strongly dependent on the oxygen vacancy of the ZnO nanoparticles. The mechanism of this CL reaction was discussed by means of the electron-spin resonance spectrum, X-ray photoelectron spectrum (XPS), and CL spectrum. The oxygen vacancy-dependent CL was attributed to the ability of the oxygen vacancy to readily adsorb and further dissociate H2O2 into active •OH radicals. Taking advantage of this oxygen vacancy-dependent CL, we presented one method for quantifying the oxygen defects in ZnO. Compared with the current evaluation techniques (XPS and Raman spectroscopy), this CL method is rapid, low-cost, and easy to operate. This work introduces the CL technique into the field of material structure-property evaluation, and provides a new approach for exploring the defect function in ZnO defect engineering.
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7
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Wang P, Ma X, Hao X, Tang B, Abudula A, Guan G. Oxygen vacancy defect engineering to promote catalytic activity toward the oxidation of VOCs: a critical review. CATALYSIS REVIEWS 2022. [DOI: 10.1080/01614940.2022.2078555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Peifen Wang
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, P. R. China
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, Japan
| | - Xuli Ma
- Department of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, P. R. China
| | - Xiaogang Hao
- Department of Chemical Engineering, Taiyuan University of Technology, Taiyuan, P. R. China
| | - Bing Tang
- School of Environmental Science and Technology, Guangdong University of Technology, Guangzhou, P.R. China
| | - Abuliti Abudula
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, Japan
| | - Guoqing Guan
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, Japan
- Energy Conversion Engineering Laboratory, Institute of Regional Innovation (IRI), Hirosaki University, Hirosaki, Japan
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8
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Chang B, Zhang L, Wu S, Sun Z, Cheng Z. Engineering single-atom catalysts toward biomedical applications. Chem Soc Rev 2022; 51:3688-3734. [PMID: 35420077 DOI: 10.1039/d1cs00421b] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Due to inherent structural defects, common nanocatalysts always display limited catalytic activity and selectivity, making it practically difficult for them to replace natural enzymes in a broad scope of biologically important applications. By decreasing the size of the nanocatalysts, their catalytic activity and selectivity will be substantially improved. Guided by this concept, the advances of nanocatalysts now enter an era of atomic-level precise control. Single-atom catalysts (denoted as SACs), characterized by atomically dispersed active sites, strikingly show utmost atomic utilization, precisely located metal centers, unique metal-support interactions and identical coordination environments. Such advantages of SACs drastically boost the specific activity per metal atom, and thus provide great potential for achieving superior catalytic activity and selectivity to functionally mimic or even outperform natural enzymes of interest. Although the size of the catalysts does matter, it is not clear whether the guideline of "the smaller, the better" is still correct for developing catalysts at the single-atom scale. Thus, it is clearly a new, urgent issue to address before further extending SACs into biomedical applications, representing an important branch of nanomedicine. This review begins by providing an overview of recent advances of synthesis strategies of SACs, which serve as a basis for the discussion of emerging achievements in improving the enzyme-like catalytic properties at an atomic level. Then, we carefully compare the structures and functions of catalysts at various scales from nanoparticles, nanoclusters, and few-atom clusters to single atoms. Contrary to conventional wisdom, SACs are not the most catalytically active catalysts in specific reactions, especially those requiring multi-site auxiliary activities. After that, we highlight the unique roles of SACs toward biomedical applications. To appreciate these advances, the challenges and prospects in rapidly growing studies of SACs-related catalytic nanomedicine are also discussed in this review.
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Affiliation(s)
- Baisong Chang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P. R. China.
| | - Liqin Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P. R. China.
| | - Shaolong Wu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P. R. China.
| | - Ziyan Sun
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, P. R. China.
| | - Zhen Cheng
- State Key Laboratory of Drug Research, Molecular Imaging Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, P. R. China. .,Bohai rim Advanced Research Institute for Drug Discovery, Yantai, 264000, China.,Molecular Imaging Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Stanford University, California 94305, USA
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9
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Preparation and characterization of Ni/Al2O3 for carbon nanofiber fabrication from CO2 hydrogenation. Catal Today 2022. [DOI: 10.1016/j.cattod.2020.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Ponnada S, Kiai MS, Gorle DB, Venkatachalam R, Saini B, Murugavel K, Nowduri A, Singhal R, Marken F, Kulandainathan AM, Nanda KK, Sharma RK, Bose RSC. Recent Status and Challenges in Multifunctional Electrocatalysis Based on 2D MXenes. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00428c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Due to their chemical and electrical characteristics, such as metallic conductivity, redox-activity in transition metals, high hydrophilicity, and adjustable surface properties, MXenes are emerging as important contributors to oxygen reduction...
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11
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Carlomagno I, Antonelli M, Aquilanti G, Bellutti P, Bertuccio G, Borghi G, Cautero G, Cirrincione D, de Giudici G, Ficorella F, Gandola M, Giuressi D, Medas D, Mele F, Menk RH, Olivi L, Orzan G, Picciotto A, Podda F, Rachevski A, Rashevskaya I, Stebel L, Vacchi A, Zampa G, Zampa N, Zorzi N, Meneghini C. Trace-element XAFS sensitivity: a stress test for a new XRF multi-detector. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:1811-1819. [PMID: 34738934 PMCID: PMC8570214 DOI: 10.1107/s1600577521008857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
X-ray absorption fine-structure (XAFS) spectroscopy can assess the chemical speciation of the elements providing their coordination and oxidation state, information generally hidden to other techniques. In the case of trace elements, achieving a good quality XAFS signal poses several challenges, as it requires high photon flux, counting statistics and detector linearity. Here, a new multi-element X-ray fluorescence detector is presented, specifically designed to probe the chemical speciation of trace 3d elements down to the p.p.m. range. The potentialities of the detector are presented through a case study: the speciation of ultra-diluted elements (Fe, Mn and Cr) in geological rocks from a calcareous formation related to the dispersal processes from Ontong (Java) volcanism (mid-Cretaceous). Trace-elements speciation is crucial in evaluating the impact of geogenic and anthropogenic harmful metals on the environment, and to evaluate the risks to human health and ecosystems. These results show that the new detector is suitable for collecting spectra of 3d elements in trace amounts in a calcareous matrix. The data quality is high enough that quantitative data analysis could be performed to determine their chemical speciation.
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Affiliation(s)
| | | | | | - Pierluigi Bellutti
- Fondazione Bruno Kessler – FBK, Trento, Italy
- TIFPA – INFN, Trento, Italy
| | | | - Giacomo Borghi
- Fondazione Bruno Kessler – FBK, Trento, Italy
- TIFPA – INFN, Trento, Italy
| | - Giuseppe Cautero
- Elettra Sincrotrone Trieste, Basovizza, Trieste, Italy
- INFN – Trieste, Padriciano, Trieste, Italy
| | - Daniela Cirrincione
- INFN – Trieste, Padriciano, Trieste, Italy
- Department of Mathematics, Computer Science, and Physics, University of Udine, Udine, Italy
| | - Giovanni de Giudici
- Department of Chemical and Geological Science, University of Cagliari, Cagliari, Italy
| | | | | | - Dario Giuressi
- Elettra Sincrotrone Trieste, Basovizza, Trieste, Italy
- INFN – Trieste, Padriciano, Trieste, Italy
| | - Daniela Medas
- Department of Chemical and Geological Science, University of Cagliari, Cagliari, Italy
| | - Filippo Mele
- Politecnico di Milano, Como, Italy
- INFN – Milano, Milano, Italy
| | - Ralf H. Menk
- Elettra Sincrotrone Trieste, Basovizza, Trieste, Italy
- INFN – Trieste, Padriciano, Trieste, Italy
- Department of Medical Imaging, University of Saskatchewan, Saskatoon, Canada SK S7N 5A2
| | - Luca Olivi
- Elettra Sincrotrone Trieste, Basovizza, Trieste, Italy
| | | | - Antonino Picciotto
- Fondazione Bruno Kessler – FBK, Trento, Italy
- TIFPA – INFN, Trento, Italy
| | - Francesca Podda
- Department of Chemical and Geological Science, University of Cagliari, Cagliari, Italy
| | | | | | - Luigi Stebel
- Elettra Sincrotrone Trieste, Basovizza, Trieste, Italy
| | - Andrea Vacchi
- INFN – Trieste, Padriciano, Trieste, Italy
- Department of Mathematics, Computer Science, and Physics, University of Udine, Udine, Italy
| | | | - Nicola Zampa
- INFN – Trieste, Padriciano, Trieste, Italy
- Department of Mathematics, Computer Science, and Physics, University of Udine, Udine, Italy
| | - Nicola Zorzi
- Fondazione Bruno Kessler – FBK, Trento, Italy
- TIFPA – INFN, Trento, Italy
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12
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Suzuki H, Iwata M, Ito M, Noguchi S. X-ray Absorption Near-Edge Spectroscopy Analysis of Indomethacin in Crystalline Forms and in Amorphous Solid Dispersions. Mol Pharm 2021; 18:3475-3483. [PMID: 34372659 DOI: 10.1021/acs.molpharmaceut.1c00405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chlorine K-edge X-ray absorption near-edge spectroscopy (XANES) measurements were performed to characterize the crystal polymorphs of identical active pharmaceutical ingredients (APIs) containing chloride atoms and their amorphous solid dispersions (ASDs). Indomethacin (IMC), of which three crystal forms (α, β, and γ) have been reported, was used as a model API. The shape of XANES spectra was unique to each IMC crystal. The analysis of the crystal structures of IMC revealed that chlorine atoms of the IMCα form had unique intermolecular interactions and halogen bonds with oxygen atoms, while those of the IMCγ form do not have any notable interactions. This result showed that XANES measurements can detect weak interatomic interactions. The shapes of the ASD spectra were clearly different from those of the crystals, suggesting that the environment around the Cl atom of IMC was different from that of the crystals. A thermal stress test was then performed to study the transformation from the amorphous form to the crystalline form of IMC in the ASD. The powder X-ray diffraction (PXRD) patterns indicated that amorphous IMC transformed into crystals during the thermal stress test. In accordance with the PXRD results, the XANES spectra also transformed from ASD to crystalline form. These results indicate that the IMC transformation could be monitored by XANES measurement. Our findings led us to conclude that XANES measurement is a novel approach for the evaluation of crystal polymorphs of APIs and the crystalline state of APIs in ASDs.
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Affiliation(s)
- Hironori Suzuki
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Moemi Iwata
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Masataka Ito
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Shuji Noguchi
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
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13
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Sattayaporn S, Rodporn S, Kidkhunthod P, Chanlek N, Yonchai C, Rujirawat S. A compact furnace for in situ X-ray absorption spectroscopy: design, fabrication and study of cationic oxidation states in Pr 6O 11 and NiO. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:455-460. [PMID: 33650557 DOI: 10.1107/s1600577520015696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
A well designed compact furnace has been designed for in situ X-ray absorption spectroscopy (XAS). It enables various heat ramps from 300 K to 1473 K. The furnace consists of heaters, a quartz tube, a circulated refrigerator and a power controller. It can generate ohmic heating via an induction process with tantalum filaments. The maximum heating rate exceeds 20 K min-1. A quartz tube with gas feedthroughs allows the mixing of gases and adjustment of the flow rate. The use of this compact furnace allows in situ XAS investigations to be carried out in transmission or fluorescence modes under controlled temperature and atmosphere. Moreover, the furnace is compact, light and well compatible to XAS. The furnace was used to study cationic oxidation states in Pr6O11 and NiO compounds under elevated temperature and reduced atmosphere using the in situ X-ray absorption near-edge structure (XANES) technique at beamline 5.2 SUT-NANOTEC-SLRI of the Synchrotron Light Research Institute, Thailand. At room temperature, Pr6O11 contains a mixture of Pr3+ and Pr4+ cations, resulting in an average oxidation state of +3.67. In situ XANES spectra of Pr (L3-edge) show that the oxidation state of Pr4+ cations was totally reduced to +3.00 at 1273 K under H2 atmosphere. Considering NiO, Ni2+ species were present under ambient conditions. At 573 K, the reduction process of Ni2+ occurred. The Ni0/Ni2+ ratio increased linearly with respect to the heating temperature. Finally, the reduction process of Ni2+ was completely finished at 770 K.
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Affiliation(s)
| | | | - Pinit Kidkhunthod
- Synchrotron Light Research Institute, Nakhon Ratchasima 30000, Thailand
| | - Narong Chanlek
- Synchrotron Light Research Institute, Nakhon Ratchasima 30000, Thailand
| | - Chutarat Yonchai
- Synchrotron Light Research Institute, Nakhon Ratchasima 30000, Thailand
| | - Saroj Rujirawat
- School of Physics, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
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14
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Panda MR, Gangwar R, Muthuraj D, Sau S, Pandey D, Banerjee A, Chakrabarti A, Sagdeo A, Weyland M, Majumder M, Bao Q, Mitra S. High Performance Lithium-Ion Batteries Using Layered 2H-MoTe 2 as Anode. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2002669. [PMID: 32803832 DOI: 10.1002/smll.202002669] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/03/2020] [Indexed: 06/11/2023]
Abstract
The major challenges faced by candidate electrode materials in lithium-ion batteries (LIBs) include their low electronic and ionic conductivities. 2D van der Waals materials with good electronic conductivity and weak interlayer interaction have been intensively studied in the electrochemical processes involving ion migrations. In particular, molybdenum ditelluride (MoTe2 ) has emerged as a new material for energy storage applications. Though 2H-MoTe2 with hexagonal semiconducting phase is expected to facilitate more efficient ion insertion/deinsertion than the monoclinic semi-metallic phase, its application as an anode in LIB has been elusive. Here, 2H-MoTe2 , prepared by a solid-state synthesis route, has been employed as an efficient anode with remarkable Li+ storage capacity. The as-prepared 2H-MoTe2 electrodes exhibit an initial specific capacity of 432 mAh g-1 and retain a high reversible specific capacity of 291 mAh g-1 after 260 cycles at 1.0 A g-1 . Further, a full-cell prototype is demonstrated by using 2H-MoTe2 anode with lithium cobalt oxide cathode, showing a high energy density of 454 Wh kg-1 (based on the MoTe2 mass) and capacity retention of 80% over 100 cycles. Synchrotron-based in situ X-ray absorption near-edge structures have revealed the unique lithium reaction pathway and storage mechanism, which is supported by density functional theory based calculations.
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Affiliation(s)
- Manas Ranjan Panda
- IITB Monash Research Academy, Bombay, Powai, Mumbai, 400076, India
- Department of Energy Science and Engineering, Electrochemical Energy Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
- Department of Mechanical and Aerospace Engineering, Nanoscale Science and Engineering Laboratory (NSEL), Monash University, Clayton, Victoria, 3800, Australia
| | - Rashmi Gangwar
- Human Resources Development Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India
| | - Divyamahalakshmi Muthuraj
- Department of Energy Science and Engineering, Electrochemical Energy Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Supriya Sau
- Department of Energy Science and Engineering, Electrochemical Energy Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Dhanshree Pandey
- Human Resources Development Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Arup Banerjee
- Human Resources Development Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Aparna Chakrabarti
- Human Resources Development Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Archna Sagdeo
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
- Synchrotrons Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India
| | - Matthew Weyland
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
- Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria, 3800, Australia
| | - Mainak Majumder
- Department of Mechanical and Aerospace Engineering, Nanoscale Science and Engineering Laboratory (NSEL), Monash University, Clayton, Victoria, 3800, Australia
| | - Qiaoliang Bao
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Sagar Mitra
- Department of Energy Science and Engineering, Electrochemical Energy Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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15
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Coduri M, Masala P, Del Bianco L, Spizzo F, Ceresoli D, Castellano C, Cappelli S, Oliva C, Checchia S, Allieta M, Szabo DV, Schlabach S, Hagelstein M, Ferrero C, Scavini M. Local Structure and Magnetism of Fe 2O 3 Maghemite Nanocrystals: The Role of Crystal Dimension. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E867. [PMID: 32365930 PMCID: PMC7279456 DOI: 10.3390/nano10050867] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 01/08/2023]
Abstract
Here we report on the impact of reducing the crystalline size on the structural and magnetic properties of γ-Fe2O3 maghemite nanoparticles. A set of polycrystalline specimens with crystallite size ranging from ~2 to ~50 nm was obtained combining microwave plasma synthesis and commercial samples. Crystallite size was derived by electron microscopy and synchrotron powder diffraction, which was used also to investigate the crystallographic structure. The local atomic structure was inquired combining pair distribution function (PDF) and X-ray absorption spectroscopy (XAS). PDF revealed that reducing the crystal dimension induces the depletion of the amount of Fe tetrahedral sites. XAS confirmed significant bond distance expansion and a loose Fe-Fe connectivity between octahedral and tetrahedral sites. Molecular dynamics revealed important surface effects, whose implementation in PDF reproduces the first shells of experimental curves. The structural disorder affects the magnetic properties more and more with decreasing the nanoparticle size. In particular, the saturation magnetization reduces, revealing a spin canting effect. Moreover, a large effective magnetic anisotropy is measured at low temperature together with an exchange bias effect, a behavior that we related to the existence of a highly disordered glassy magnetic phase.
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Affiliation(s)
- Mauro Coduri
- Department of Chemistry, University of Pavia, viale Taramelli 16, 27100 Pavia, Italy
| | - Paolo Masala
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
| | - Lucia Del Bianco
- Department of Physics and Earth Sciences, University of Ferrara, via Saragat 1, 44122 Ferrara, Italy; (L.D.B.); (F.S.)
| | - Federico Spizzo
- Department of Physics and Earth Sciences, University of Ferrara, via Saragat 1, 44122 Ferrara, Italy; (L.D.B.); (F.S.)
| | - Davide Ceresoli
- National Research Council of Italy, Institute of Chemical Science and Technology (CNR-SCITEC), 20133 Milano, Italy;
| | - Carlo Castellano
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
| | - Serena Cappelli
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
| | - Cesare Oliva
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
| | | | - Mattia Allieta
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
| | - Dorothee-Vinga Szabo
- Karlsruhe Institute of Technology, Institute for Applied Materials (IAM) and Karlsruhe Nano Micro Facility (KNMF), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (D.-V.S.); (S.S.)
| | - Sabine Schlabach
- Karlsruhe Institute of Technology, Institute for Applied Materials (IAM) and Karlsruhe Nano Micro Facility (KNMF), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; (D.-V.S.); (S.S.)
| | - Michael Hagelstein
- Karlsruhe Institute of Technology, Institute for Beam Physics and Technology (IBPT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;
| | - Claudio Ferrero
- European Synchrotron Radiation Facility, 38000 Grenoble, France;
| | - Marco Scavini
- Department of Chemistry, University of Milan, via Golgi 19, 20131 Milano, Italy; (P.M.); (C.C.); (S.C.); (C.O.); (M.A.)
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16
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Pandey GC, Nemkovski K, Su Y, Rath C. Evidence of anomalous conventional and spontaneous exchange bias, high coercivity in Fe doped NiCr 2O 4 spinel. Dalton Trans 2020; 49:4502-4517. [PMID: 32193522 DOI: 10.1039/d0dt00124d] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NiCr2-xFexO4 (x = 0 and 0.2) polycrystalline ceramics have been synthesized successfully through a simple co-precipitation technique to study the evolution of structural and magnetic properties by doping Fe. X-ray diffraction (XRD) reveals that the high-temperature cubic phase (space group Fd3[combining macron]m) observed at 320 K in bulk NiCr2O4 is stabilized at room temperature by decreasing the particle size to nanometer in x = 0 as well as after incorporating 20 at% Fe in the NiCr2O4 lattice. The cation distribution obtained from X-ray absorption fine structure (XAFS) analysis illustrates that while in x = 0, Ni2+ and Cr3+ ions occupy the tetrahedral (A) and octahedral (B) sites, respectively, x = 0.2, Fe3+ and Cr3+ ions occupy the A and B sites, respectively, and Ni2+ ions are distributed among the A and B sites. This transformation from the normal to mixed spinel structure strongly affects the magnetic properties. While the paramagnetic to long-range ferrimagnetic ordering temperature TC is enhanced from 71 to 192 K, significantly large coercive field (HC) of ∼29 kOe is observed for x = 0.2 as compared to the HC ∼13 kOe for x = 0. Moreover, unusually large conventional and spontaneous exchange bias fields of ∼26 and ∼2.6 kOe are observed for x = 0.2, which is absent for x = 0. The presence of anomalous exchange bias field is ascribed to the unidirectional exchange anisotropy between the two magnetic sublattices at A and B sites. The training effect of the exchange bias field is discussed using a phenomenological model, which considers the contribution from irreversible uncompensated spins that modify the exchange anisotropy at the interface between A and B magnetic sublattices. In addition, diffuse neutron scattering (DNS) with XYZ analysis is employed for both compositions to clearly illustrate the low-temperature peculiar magnetic phase transitions such as spin spiral transition, TS and spin lock-in transition, Tl. The DNS demonstrates that while Tl decreases from 10 K to 7 K with the incorporation of Fe in the NiCr2O4 lattice, TS significantly increases from 28 K to 50 K.
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Affiliation(s)
- G C Pandey
- School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005, India.
| | - K Nemkovski
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenbergstr. 1, 85748 Garching, Germany
| | - Y Su
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Lichtenbergstr. 1, 85748 Garching, Germany
| | - Chandana Rath
- School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, 221005, India.
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17
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Bokarev SI, Kühn O. Theoretical X‐ray spectroscopy of transition metal compounds. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1433] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | - Oliver Kühn
- Institut für Physik Universität Rostock Rostock Germany
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18
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Examination of Natural and Standard Fe 3O 4 Powders Using X-Ray Absorption Near-Edge Spectroscopy (XANES). ACTA ACUST UNITED AC 2019. [DOI: 10.4028/www.scientific.net/msf.964.40] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Investigation of Fe K-edge X-Ray Absorption Near Edge Spectroscopy (XANES) spectra of Fe3O4 (FeO.Fe2O3) from natural source compared with the Fe3O4 standard is presented. The natural Fe3O4 powder was prepared from ironstone of Tanah Laut, Kalimantan Selatan by co-precipitation method. XANES measurements in transmission mode were performed at the Synchrotron Light Research Institute (SLRI), Nakhon Ratchasima, Thailand. XRD phase analysis confirms that the synthesized Fe3O4 powder is a single phase, but it cannot determine the proportion of Fe2O3 and FeO in the structure. TEM measurement confirms that the particle size of natural Fe3O4 about 10 nm. Qualitative analysis of the pre-edge XANES data revealed that the absorbing atom in the XAS measurement is Fe3+. Meanwhile, the absorption edge (E0) values of natural and standard Fe3O4 powders were 7126.44 eV and 7125.02 eV, respectively. The proportion was then acquired using XANES data analysis through Linear Combination Fitting (LCF). It was found that the natural Fe3O4 sample consisted of 98 wt. % Fe2O3 and 2 wt.% FeO, while the standard Fe3O4 powder consisted of 96 wt. % Fe2O3 and 4 wt. % FeO. The mechanism of the absorption in both samples is also described and compared.
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19
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Ye K, Li K, Lu Y, Guo Z, Ni N, Liu H, Huang Y, Ji H, Wang P. An overview of advanced methods for the characterization of oxygen vacancies in materials. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.05.002] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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20
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Zheng Q, Zhang Y, Montazerian M, Gulbiten O, Mauro JC, Zanotto ED, Yue Y. Understanding Glass through Differential Scanning Calorimetry. Chem Rev 2019; 119:7848-7939. [DOI: 10.1021/acs.chemrev.8b00510] [Citation(s) in RCA: 154] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Qiuju Zheng
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Yanfei Zhang
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Maziar Montazerian
- Vitreous Materials Laboratory (LaMaV), Department of Materials Engineering (DEMa), Federal University of São Carlos (UFSCar), 13.565-905 São Carlos, SP, Brazil
| | - Ozgur Gulbiten
- Science and Technology Division, Corning Incorporated, Corning, New York 14831, United States
| | - John C. Mauro
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Edgar D. Zanotto
- Vitreous Materials Laboratory (LaMaV), Department of Materials Engineering (DEMa), Federal University of São Carlos (UFSCar), 13.565-905 São Carlos, SP, Brazil
| | - Yuanzheng Yue
- School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
- Department of Chemistry and Bioscience, Aalborg University, DK-9220 Aalborg, Denmark
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Celestian AJ, Lively J, Xu W. In Situ Cs and H Exchange into Gaidonnayite and Proposed Mechanisms of Ion Diffusion. Inorg Chem 2019; 58:1919-1928. [PMID: 30653312 DOI: 10.1021/acs.inorgchem.8b02834] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The microporous mineral gaidonnayite Na2ZrSi3O9·2H2O was studied to better understand its ion-exchange mechanisms, specifically for Cs+ and H+ ions. In situ Raman spectroscopy, in situ X-ray diffraction (XRD), simultaneous thermogravimetric analysis and differential scanning calorimetry (TGA/DSC), and in situ X-ray fluorescence were used to determine the exchange processes involved. The Raman spectra contain strong peaks that can be attributed to the vibrational modes for the 3MR symmetric stretch at 500 cm-1, Si-O-Zr-O chain stretches at 938 cm-1, and Si-O stretching in the 1000-1100 cm-1 range. The most prominent Raman shift during ion exchange is found near the 520 cm-1 peak, which corresponds to distortions of the 3MR substructure of gaidonnayite. In all instances of this study, the 3MR exhibited the highest amount of distortion during ion exchange, and the evolution of this distortion is compared to unit-cell changes as measured from XRD data and elemental changes via XRF. The correlations between the Raman, XRD, and XRF data show rapid deformation of the 3MR during the onset of H+ ion exchange in the Na form of gaidonnayite. Even when unit-cell volume changes were small (<3 Å3) as in the cases for Cs+ into Na-gaidonnayite and Cs+ into H-gaidonnayite, significant changes in the ≈520 cm-1 peak were measured. By comparing XRD data and Raman data, and verifying the cation uptake by XRF, we were able to identify and confirm conformational changes and distortions in the crystal structure before, during, and after Cs+ and H+ exchange. Cs exchange occurred the fastest and with the greatest capacity when starting in the H-form at room temperature, and at elevated temperatures when starting in the Na-form.
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Affiliation(s)
- Aaron J Celestian
- Department of Mineral Sciences , Natural History Museum of Los Angeles County , 900 Exposition Boulevard , Los Angeles , California 90007 , United States
| | - Jason Lively
- Department of Geography and Geology , Western Kentucky University , 1906 College Heights Boulevard , Bowling Green , Kentucky 42101 , United States
| | - Wenqian Xu
- X-ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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