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Terzoudis-Lumsden EWC, Petersen TC, Brown HG, Pelz PM, Ophus C, Findlay SD. Resolution of Virtual Depth Sectioning from Four-Dimensional Scanning Transmission Electron Microscopy. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1409-1421. [PMID: 37488824 DOI: 10.1093/micmic/ozad068] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 03/15/2023] [Accepted: 05/25/2023] [Indexed: 07/26/2023]
Abstract
One approach to three-dimensional structure determination using the wealth of scattering data in four-dimensional (4D) scanning transmission electron microscopy (STEM) is the parallax method proposed by Ophus et al. (2019. Advanced phase reconstruction methods enabled by 4D scanning transmission electron microscopy, Microsc Microanal25, 10-11), which determines the scattering matrix and uses it to synthesize a virtual depth-sectioning reconstruction of the sample structure. Drawing on an equivalence with a hypothetical confocal imaging mode, we derive contrast transfer and point spread functions for this parallax method applied to weakly scattering objects, showing them identical to earlier depth-sectioning STEM modes when only bright field signal is used, but that improved depth resolution is possible if dark field signal can be used. Through a simulation-based study of doped Si, we show that this depth resolution is preserved for thicker samples, explore the impact of shot noise on the parallax reconstructions, discuss challenges to making use of dark field signal, and identify cases where the interpretation of the parallax reconstruction breaks down.
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Affiliation(s)
| | - T C Petersen
- School of Physics and Astronomy, Monash University, Melbourne, VIC 3800, Australia
- Monash Centre for Electron Microscopy, Monash University, Melbourne, VIC 3800, Australia
| | - H G Brown
- Ian Holmes Imaging Center, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC 3052, Australia
| | - P M Pelz
- Institute of Micro- and Nanostructure Research and Center for Nanoanalysis and Electron Microscopy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Bavaria 91058, Germany
| | - C Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - S D Findlay
- School of Physics and Astronomy, Monash University, Melbourne, VIC 3800, Australia
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Pulinthanathu Sree S, Breynaert E, Kirschhock CEA, Martens JA. Hierarchical COK-X Materials for Applications in Catalysis and Adsorptive Separation and Controlled Release. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.810443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Over the years, COK has developed a family of silicate materials and metal–organic framework hybrids with hierarchical porosity and functionality, coined zeogrids, zeotiles, and COK-x (stemming from the Flemish name of the laboratory “Centrum voor Oppervlaktechemie en Katalyse”). Several of these materials have unique features relevant to heterogeneous catalysis, molecular separation, and controlled release and found applications in the field of green chemistry, environmental protection, and pharmaceutical formulation. Discovery of a new material typically occurs by serendipity, but the research was always guided by hypothesis. This review provides insight in the process of tuning initial research hypotheses to match material properties to specific applications. This review describes the synthesis, structure, properties, and applications of 12 different materials. Some have simple synthesis protocols, facilitating upscaling and reproduction and rendering them attractive also in this respect.
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He Y, Ming W, Shen R, Chen J. IDART: An Improved Discrete Tomography Algorithm for Reconstructing Images With Multiple Gray Levels. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2022; 31:2608-2619. [PMID: 35316179 DOI: 10.1109/tip.2022.3152632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The discrete algebraic reconstruction technique has many advantages in computed tomography and electron tomography. However, the number of gray levels and the absolute gray values that should be known in advance are typically not available in experiments especially when there are many gray levels in the image. In this paper, we report an automatic discrete tomography reconstruction algorithm to improve its feasibility in practice, without needing to know these two parameters. In our algorithm, the number of gray levels is estimated by labeling the connected components in the tomogram and the absolute values of them are determined by the modal value of each domain. The proposed algorithm was extensively validated on both simulated and experimental datasets. The results show that our algorithm can accurately recover not only the morphology but also the gray levels of the interested objects, even in the images with multiple gray levels. It is demonstrated that the presented algorithm is robust for eliminating missing wedge artifacts and tolerable for noisy data.
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Albrecht W, Van Aert S, Bals S. Three-Dimensional Nanoparticle Transformations Captured by an Electron Microscope. Acc Chem Res 2021; 54:1189-1199. [PMID: 33566587 DOI: 10.1021/acs.accounts.0c00711] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
ConspectusThree-dimensional (3D) morphology and composition govern the properties of nanoparticles (NPs). However, due to their high surface-to-volume ratio, the morphology and composition of nanomaterials are not as static as those for their bulk counterparts. One major influence is the increase in relative contribution of surface diffusion, which underlines rapid reshaping of NPs in response to changes in their environment. If not accounted for, these effects might affect the robustness of prospective NPs in practically relevant conditions, such as elevated temperatures, intense light illumination, or changing chemical environments. In situ techniques are promising tools to study NP transformations under relevant conditions. Among those tools, in situ transmission electron microscopy (TEM) provides an elegant platform to directly visualize NP changes down to the atomic scale. By the use of specialized holders or microscopes, external stimuli, such as heat, or environments, such as gas and liquids, can be controllably introduced inside the TEM. In addition, TEM is also a valuable tool to determine NP transformations upon ex situ stimuli such as laser excitation. However, standard TEM yields two-dimensional (2D) projection images of 3D objects. With the growing complexity of NP shapes and compositions, the information that is obtained in this manner is often insufficient to understand intricate diffusion dynamics.In this Account, we describe recent progress on measuring NP transformations in 3D inside the electron microscope. First, we discuss existing possibilities to obtain 3D information using either tomographic methods or the so-called atom counting technique, which utilizes single projection images. Next, we show how these techniques can be combined with in situ holders to quantify diffusion processes on a single nanoparticle level. Specifically, we focus on anisotropic metal NPs at elevated temperatures and in varying gas environments. Anisotropic metal NPs are important for plasmonic applications, because sharp tips and edges result in strong electromagnetic field enhancements. By electron tomography, surface diffusion as well as elemental diffusion can be tracked in monometallic and bimetallic NPs, which can then be directly related to changes in plasmonic properties of these systems. By atom counting, it has furthermore become possible to monitor the evolution of crystalline facets of metal NPs under gas and heat treatments, a change that influences catalytic properties. Next to in situ processes, we also demonstrate the value of electron tomography to assess external laser-induced NP transformations, making it viable to detect structural changes with atomic resolution. The application of the proposed methodologies is by far not limited to metal nanoparticles. In the final section, we therefore outline future material research that can benefit from tracking NP transformations from 3D techniques.
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Affiliation(s)
- Wiebke Albrecht
- EMAT and NANOlab Center of Excellence, University of Antwerp, B-2020 Antwerp, Belgium
| | - Sandra Van Aert
- EMAT and NANOlab Center of Excellence, University of Antwerp, B-2020 Antwerp, Belgium
| | - Sara Bals
- EMAT and NANOlab Center of Excellence, University of Antwerp, B-2020 Antwerp, Belgium
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Chen Q, Dwyer C, Sheng G, Zhu C, Li X, Zheng C, Zhu Y. Imaging Beam-Sensitive Materials by Electron Microscopy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1907619. [PMID: 32108394 DOI: 10.1002/adma.201907619] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 12/20/2019] [Indexed: 05/15/2023]
Abstract
Electron microscopy allows the extraction of multidimensional spatiotemporally correlated structural information of diverse materials down to atomic resolution, which is essential for figuring out their structure-property relationships. Unfortunately, the high-energy electrons that carry this important information can cause damage by modulating the structures of the materials. This has become a significant problem concerning the recent boost in materials science applications of a wide range of beam-sensitive materials, including metal-organic frameworks, covalent-organic frameworks, organic-inorganic hybrid materials, 2D materials, and zeolites. To this end, developing electron microscopy techniques that minimize the electron beam damage for the extraction of intrinsic structural information turns out to be a compelling but challenging need. This article provides a comprehensive review on the revolutionary strategies toward the electron microscopic imaging of beam-sensitive materials and associated materials science discoveries, based on the principles of electron-matter interaction and mechanisms of electron beam damage. Finally, perspectives and future trends in this field are put forward.
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Affiliation(s)
- Qiaoli Chen
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Christian Dwyer
- Department of Physics, Arizona State University, Tempe, AZ, 85287-1504, USA
| | - Guan Sheng
- Advanced Membranes and Porous Materials Center, Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Chongzhi Zhu
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Xiaonian Li
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Changlin Zheng
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200438, China
| | - Yihan Zhu
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China
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Six N, De Beenhouwer J, Sijbers J. poly-DART: A discrete algebraic reconstruction technique for polychromatic X-ray CT. OPTICS EXPRESS 2019; 27:33670-33682. [PMID: 31878430 DOI: 10.1364/oe.27.033670] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 09/08/2019] [Indexed: 06/10/2023]
Abstract
The discrete algebraic reconstruction technique (DART) is a tomographic method to reconstruct images from X-ray projections in which prior knowledge on the number of object materials is exploited. In monochromatic X-ray CT (e.g., synchrotron), DART has been shown to lead to high-quality reconstructions, even with a low number of projections or a limited scanning view. However, most X-ray sources are polychromatic, leading to beam hardening effects, which significantly degrade the performance of DART. In this work, we propose a new discrete tomography algorithm, poly-DART, that exploits sparsity in the attenuation values using DART and simultaneously accounts for the polychromatic nature of the X-ray source. The results show that poly-DART leads to a vastly improved segmentation on polychromatic data obtained from Monte Carlo simulations as well as on experimental data, compared to DART.
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Hungría AB, Calvino JJ, Hernández-Garrido JC. HAADF-STEM Electron Tomography in Catalysis Research. Top Catal 2019. [DOI: 10.1007/s11244-019-01200-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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8
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Wan W, Su J, Zou XD, Willhammar T. Transmission electron microscopy as an important tool for characterization of zeolite structures. Inorg Chem Front 2018. [DOI: 10.1039/c8qi00806j] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review presents various TEM techniques including electron diffraction, high-resolution TEM and scanning TEM imaging, and electron tomography and their applications for structure characterization of zeolite materials.
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Affiliation(s)
- W. Wan
- Inorganic and Structural Chemistry
- Department of Materials and Environmental Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - J. Su
- Inorganic and Structural Chemistry
- Department of Materials and Environmental Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - X. D. Zou
- Inorganic and Structural Chemistry
- Department of Materials and Environmental Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - T. Willhammar
- Inorganic and Structural Chemistry
- Department of Materials and Environmental Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
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9
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Van de Casteele E, Perilli E, Van Aarle W, Reynolds KJ, Sijbers J. Discrete tomography in an in vivo small animal bone study. J Bone Miner Metab 2018; 36:40-53. [PMID: 28243794 DOI: 10.1007/s00774-017-0815-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
This study aimed at assessing the feasibility of a discrete algebraic reconstruction technique (DART) to be used in in vivo small animal bone studies. The advantage of discrete tomography is the possibility to reduce the amount of X-ray projection images, which makes scans faster and implies also a significant reduction of radiation dose, without compromising the reconstruction results. Bone studies are ideal for being performed with discrete tomography, due to the relatively small number of attenuation coefficients contained in the image [namely three: background (air), soft tissue and bone]. In this paper, a validation is made by comparing trabecular bone morphometric parameters calculated from images obtained by using DART and the commonly used standard filtered back-projection (FBP). Female rats were divided into an ovariectomized (OVX) and a sham-operated group. In vivo micro-CT scanning of the tibia was done at baseline and at 2, 4, 8 and 12 weeks after surgery. The cross-section images were reconstructed using first the full set of projection images and afterwards reducing them in number to a quarter and one-sixth (248, 62, 42 projection images, respectively). For both reconstruction methods, similar changes in morphometric parameters were observed over time: bone loss for OVX and bone growth for sham-operated rats, although for DART the actual values were systematically higher (bone volume fraction) or lower (structure model index) compared to FBP, depending on the morphometric parameter. The DART algorithm was, however, more robust when using fewer projection images, where the standard FBP reconstruction was more prone to noise, showing a significantly bigger deviation from the morphometric parameters obtained using all projection images. This study supports the use of DART as a potential alternative method to FBP in X-ray micro-CT animal studies, in particular, when the number of projections has to be drastically minimized, which directly reduces scanning time and dose.
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Affiliation(s)
- Elke Van de Casteele
- iMinds, VisionLab, Department of Physics, University of Antwerp (CDE), Universiteitsplein 1, Building N, 2610, Antwerp, Belgium.
| | - Egon Perilli
- Medical Device Research Institute, School of Computer Science, Engineering and Mathematics, Flinders University, GPO Box 2100, Adelaide, SA, 5001, Australia
| | - Wim Van Aarle
- iMinds, VisionLab, Department of Physics, University of Antwerp (CDE), Universiteitsplein 1, Building N, 2610, Antwerp, Belgium
| | - Karen J Reynolds
- Medical Device Research Institute, School of Computer Science, Engineering and Mathematics, Flinders University, GPO Box 2100, Adelaide, SA, 5001, Australia
| | - Jan Sijbers
- iMinds, VisionLab, Department of Physics, University of Antwerp (CDE), Universiteitsplein 1, Building N, 2610, Antwerp, Belgium
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10
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Zhuge X, Jinnai H, Dunin-Borkowski RE, Migunov V, Bals S, Cool P, Bons AJ, Batenburg KJ. Automated discrete electron tomography – Towards routine high-fidelity reconstruction of nanomaterials. Ultramicroscopy 2017; 175:87-96. [DOI: 10.1016/j.ultramic.2017.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 12/29/2016] [Accepted: 01/21/2017] [Indexed: 11/27/2022]
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11
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Liang Z, Guan Y, Liu G, Chen X, Li F, Guo P, Tian Y. A modified discrete algebraic reconstruction technique for multiple grey image reconstruction for limited angle range tomography. JOURNAL OF SYNCHROTRON RADIATION 2016; 23:606-616. [PMID: 26917150 DOI: 10.1107/s1600577516000564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 01/11/2016] [Indexed: 06/05/2023]
Abstract
The `missing wedge', which is due to a restricted rotation range, is a major challenge for quantitative analysis of an object using tomography. With prior knowledge of the grey levels, the discrete algebraic reconstruction technique (DART) is able to reconstruct objects accurately with projections in a limited angle range. However, the quality of the reconstructions declines as the number of grey levels increases. In this paper, a modified DART (MDART) was proposed, in which each independent region of homogeneous material was chosen as a research object, instead of the grey values. The grey values of each discrete region were estimated according to the solution of the linear projection equations. The iterative process of boundary pixels updating and correcting the grey values of each region was executed alternately. Simulation experiments of binary phantoms as well as multiple grey phantoms show that MDART is capable of achieving high-quality reconstructions with projections in a limited angle range. The interesting advancement of MDART is that neither prior knowledge of the grey values nor the number of grey levels is necessary.
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Affiliation(s)
- Zhiting Liang
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Yong Guan
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Gang Liu
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Xiangyu Chen
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Fahu Li
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Pengfei Guo
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
| | - Yangchao Tian
- National Synchrotion Radiation Laboratory, University of Science and Technology of China, 3#419, No.42 Hezuohua South Road, Hefei, Anhui 230029, People's Republic of China
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Melinte G, Georgieva V, Springuel-Huet MA, Nossov A, Ersen O, Guenneau F, Gedeon A, Palčić A, Bozhilov KN, Pham-Huu C, Qiu S, Mintova S, Valtchev V. 3D Study of the Morphology and Dynamics of Zeolite Nucleation. Chemistry 2015; 21:18316-27. [PMID: 26503177 DOI: 10.1002/chem.201501919] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Indexed: 11/06/2022]
Abstract
The principle aspects and constraints of the dynamics and kinetics of zeolite nucleation in hydrogel systems are analyzed on the basis of a model Na-rich aluminosilicate system. A detailed time-series EMT-type zeolite crystallization study in the model hydrogel system was performed to elucidate the topological and temporal aspects of zeolite nucleation. A comprehensive set of analytical tools and methods was employed to analyze the gel evolution and complement the primary methods of transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR) spectroscopy. TEM tomography reveals that the initial gel particles exhibit a core-shell structure. Zeolite nucleation is topologically limited to this shell structure and the kinetics of nucleation is controlled by the shell integrity. The induction period extends to the moment when the shell is consumed and the bulk solution can react with the core of the gel particles. These new findings, in particular the importance of the gel particle shell in zeolite nucleation, can be used to control the growth process and properties of zeolites formed in hydrogels.
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Affiliation(s)
- Georgian Melinte
- IPCMS UMR7504 CNRS, Université de Strasbourg, 23, rue du Loess BP 43, 67034 Strasbourg (France)
| | - Veselina Georgieva
- LCS, ENSICAEN, University of Caen - CNRS, 6, Bd Maréchal Juin, 14000 Caen (France)
| | - Marie-Anne Springuel-Huet
- Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, 11, place Marcelin Berthelot, 75005 Paris (France)
| | - Andreï Nossov
- Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, 11, place Marcelin Berthelot, 75005 Paris (France)
| | - Ovidiu Ersen
- IPCMS UMR7504 CNRS, Université de Strasbourg, 23, rue du Loess BP 43, 67034 Strasbourg (France)
| | - Flavien Guenneau
- Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, 11, place Marcelin Berthelot, 75005 Paris (France)
| | - Antoine Gedeon
- Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, 11, place Marcelin Berthelot, 75005 Paris (France)
| | - Ana Palčić
- LCS, ENSICAEN, University of Caen - CNRS, 6, Bd Maréchal Juin, 14000 Caen (France)
| | - Krassimir N Bozhilov
- Central Facility for Advanced Microscopy and Microanalysis, University of California, Riverside, 900 University Avenue, Riverside, CA 92521 (USA)
| | - Cuong Pham-Huu
- ICPEES, ECPM, Université de Strasbourg, 25, rue Becquerel, 67087 Strasbourg (France)
| | - Shilun Qiu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, 2699 Qianjin Street, Changchun, Jilin 130012 (P.R. China)
| | - Svetlana Mintova
- LCS, ENSICAEN, University of Caen - CNRS, 6, Bd Maréchal Juin, 14000 Caen (France)
| | - Valentin Valtchev
- LCS, ENSICAEN, University of Caen - CNRS, 6, Bd Maréchal Juin, 14000 Caen (France).
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Fabrication of Nanostructured Platinum with Multilevel Porosity for Low Impedance Biomedical Recording and Stimulation Electrodes. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.proeng.2015.08.635] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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14
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Chen D, Goris B, Bleichrodt F, Mezerji HH, Bals S, Batenburg KJ, de With G, Friedrich H. The properties of SIRT, TVM, and DART for 3D imaging of tubular domains in nanocomposite thin-films and sections. Ultramicroscopy 2014; 147:137-48. [DOI: 10.1016/j.ultramic.2014.08.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 07/25/2014] [Accepted: 08/03/2014] [Indexed: 10/24/2022]
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Do MH, Wang T, Cheng DG, Chen F, Zhan X, Rioux RM, Gong J. Simple strategies for fabrication of a periodic mesoporous aluminosilicate with crystalline walls. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:4249-4256. [PMID: 25049062 DOI: 10.1002/smll.201401486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Indexed: 06/03/2023]
Abstract
An alkali-assisted cooperative assembly process of two different templating systems with aluminosilicate precursors is described. A highly ordered mesoporous zeolite with the 2D hexagonal symmetry mesospores and MFI zeolitic framework walls is synthesized. This method also allows the preparation of ZSM-5 with c- or b-axis-aligned mesopores. The materials have promising catalytic activities for organic reactions involving bulky molecules.
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Affiliation(s)
- Manh Huy Do
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, Zhejiang, China; Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh, Vietnam
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Bals S, Goris B, Liz-Marzán L, Van Tendeloo G. Dreidimensionale Charakterisierung von Edelmetall-Nanopartikeln und deren Anordnungen mithilfe von Elektronentomographie. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201401059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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Bals S, Goris B, Liz-Marzán LM, Van Tendeloo G. Three-Dimensional Characterization of Noble-Metal Nanoparticles and their Assemblies by Electron Tomography. Angew Chem Int Ed Engl 2014; 53:10600-10. [DOI: 10.1002/anie.201401059] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Indexed: 11/11/2022]
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18
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Kundu P, Heidari H, Bals S, Ravishankar N, Van Tendeloo G. Formation and Thermal Stability of Gold-Silica Nanohybrids: Insight into the Mechanism and Morphology by Electron Tomography. Angew Chem Int Ed Engl 2014; 53:3970-4. [DOI: 10.1002/anie.201309288] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/06/2013] [Indexed: 01/08/2023]
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19
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Kundu P, Heidari H, Bals S, Ravishankar N, Van Tendeloo G. Formation and Thermal Stability of Gold-Silica Nanohybrids: Insight into the Mechanism and Morphology by Electron Tomography. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201309288] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Laloum D, Lorut F, Bertheau J, Audoit G, Bleuet P. Deep sub micrometer imaging of defects in copper pillars by X-ray tomography in a SEM. Micron 2013; 58:1-8. [PMID: 24316374 DOI: 10.1016/j.micron.2013.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 10/28/2013] [Accepted: 10/28/2013] [Indexed: 10/26/2022]
Abstract
The potential of X-ray nanotomography hosted in a SEM in presented in this paper. In order to improve the detail detectability of this system, which is directly related to the X-ray source size, thin metal layers have been studied and installed in the equipment. A 3D resolution pattern has been created in order to determine the smallest detectable features by this setup. This sample is a 25 μm diameter copper pillar in which size-controlled holes have been milled using a plasma-focused ion beam. This pattern has then been scanned and the resulting 3D reconstruction demonstrates that the instrument is able to detect 500 nm diameter voids in a copper interconnection, as used in 3D integration.
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Affiliation(s)
- D Laloum
- STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France.
| | - F Lorut
- STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles, France
| | - J Bertheau
- STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles, France; CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
| | - G Audoit
- CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
| | - P Bleuet
- CEA, LETI, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
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21
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Geometric reconstruction methods for electron tomography. Ultramicroscopy 2013; 128:42-54. [DOI: 10.1016/j.ultramic.2013.01.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 01/07/2013] [Accepted: 01/19/2013] [Indexed: 11/17/2022]
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22
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Zečević J, van der Eerden AMJ, Friedrich H, de Jongh PE, de Jong KP. Heterogeneities of the nanostructure of platinum/zeolite y catalysts revealed by electron tomography. ACS NANO 2013; 7:3698-3705. [PMID: 23521107 DOI: 10.1021/nn400707p] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
To develop structure-performance relationships for important catalysts, a detailed characterization of their morphology is essential. Using electron tomography, we determined in three dimensions the structure of Pt/zeolite Y bifunctional catalysts. Optimum experimental conditions enabled for the first time high-resolution 3D imaging of Pt particles as small as 1 nm located inside zeolite micropores. Semiautomated image analysis of 3D reconstructions provided an efficient study of numbers, size distributions, and interparticle distances of thousands of Pt particles within individual zeolite crystals. Upon extending this approach to a number of zeolite crystals of one batch of Pt/zeolite Y catalyst, heterogeneities were revealed. The Pt loading, an important parameter for catalyst performance, varied between zeolite crystals up to a factor of 35. This discovery calls for re-evaluation of catalyst preparation methods and suggests potential for lowering the nominal loading with noble metals.
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Affiliation(s)
- Jovana Zečević
- Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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Goris B, Roelandts T, Batenburg K, Heidari Mezerji H, Bals S. Advanced reconstruction algorithms for electron tomography: From comparison to combination. Ultramicroscopy 2013; 127:40-7. [DOI: 10.1016/j.ultramic.2012.07.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Schryvers D, Cao S, Tirry W, Idrissi H, Van Aert S. Advanced three-dimensional electron microscopy techniques in the quest for better structural and functional materials. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2013; 14:014206. [PMID: 27877554 PMCID: PMC5090572 DOI: 10.1088/1468-6996/14/1/014206] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 11/19/2012] [Indexed: 05/26/2023]
Abstract
After a short review of electron tomography techniques for materials science, this overview will cover some recent results on different shape memory and nanostructured metallic systems obtained by various three-dimensional (3D) electron imaging techniques. In binary Ni-Ti, the 3D morphology and distribution of Ni4Ti3 precipitates are investigated by using FIB/SEM slice-and-view yielding 3D data stacks. Different quantification techniques will be presented including the principal ellipsoid for a given precipitate, shape classification following a Zingg scheme, particle distribution function, distance transform and water penetration. The latter is a novel approach to quantifying the expected matrix transformation in between the precipitates. The different samples investigated include a single crystal annealed with and without compression yielding layered and autocatalytic precipitation, respectively, and a polycrystal revealing different densities and sizes of the precipitates resulting in a multistage transformation process. Electron tomography was used to understand the interaction between focused ion beam-induced Frank loops and long dislocation structures in nanobeams of Al exhibiting special mechanical behaviour measured by on-chip deposition. Atomic resolution electron tomography is demonstrated on Ag nanoparticles in an Al matrix.
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Affiliation(s)
| | - S Cao
- Now at Department of Metallic Materials Science & Engineering, South China University of Technology (SCUT), Guangzhou, Wushan 510640, People’s Republic of China
| | - W Tirry
- Now at AtlasCopco, Aartselaar, Belgium
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25
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Van Tendeloo G, Bals S, Van Aert S, Verbeeck J, Van Dyck D. Advanced electron microscopy for advanced materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:5655-5675. [PMID: 22907862 DOI: 10.1002/adma.201202107] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Indexed: 06/01/2023]
Abstract
The idea of this Review is to introduce newly developed possibilities of advanced electron microscopy to the materials science community. Over the last decade, electron microscopy has evolved into a full analytical tool, able to provide atomic scale information on the position, nature, and even the valency atoms. This information is classically obtained in two dimensions (2D), but can now also be obtained in 3D. We show examples of applications in the field of nanoparticles and interfaces.
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Jin J, Zhang X, Li Y, Li H, Wu W, Cui Y, Chen Q, Li L, Gu J, Zhao W, Shi J. A Simple Route to Synthesize Mesoporous ZSM-5 Templated by Ammonium-Modified Chitosan. Chemistry 2012; 18:16549-55. [DOI: 10.1002/chem.201201614] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 09/19/2012] [Indexed: 11/09/2022]
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27
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van Aarle W, Batenburg KJ, Sijbers J. Automatic parameter estimation for the discrete algebraic reconstruction technique (DART). IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2012; 21:4608-4621. [PMID: 22752136 DOI: 10.1109/tip.2012.2206042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Computed tomography (CT) is a technique for noninvasive imaging of physical objects. In the discrete algebraic reconstruction technique (DART), prior knowledge about the material's densities is exploited to obtain high quality reconstructed images from a limited number of its projections. In practice, this prior knowledge is typically not readily available. Here, a fully automatic method, called projection distance minimization DART (PDM-DART), is proposed in which the optimal grey level parameters are adaptively estimated during the reconstruction process. To apply PDM-DART, only the number of different grey levels should be known in advance. Simulation as well as real μCT experiments show that PDM-DART is capable of computing reconstructed images of which the quality is similar to reconstructions computed by conventional DART based on exact prior knowledge, thereby eliminating the need for tedious and error-prone user interaction.
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Affiliation(s)
- Wim van Aarle
- IBBT-Vision Lab, University of Antwerp, Antwerp 2018, Belgium.
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28
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Potential of ordered mesoporous silica for oral delivery of poorly soluble drugs. Ther Deliv 2012; 2:1079-91. [PMID: 22833866 DOI: 10.4155/tde.11.66] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The use of ordered mesoporous silica is one of the more recent and rapidly developing formulation techniques for enhancing the solubility of poorly water-soluble drugs. Their large surface area and pore volume make ordered mesoporous silica materials excellent candidates for efficient drug loading and rapid release. While this new approach offers many promising advantages, further research is still necessary to elucidate the molecular mechanisms and to improve our scientific insight into the behavior of this system. In this review, the significant developments to date are presented and research challenges highlighted. Aspects of downstream processability are discussed in view of their special bulk powder properties and unique pore architecture. Lastly, perspectives for successful oral dosage form development are presented.
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Roelandts T, Batenburg K, Biermans E, Kübel C, Bals S, Sijbers J. Accurate segmentation of dense nanoparticles by partially discrete electron tomography. Ultramicroscopy 2012; 114:96-105. [DOI: 10.1016/j.ultramic.2011.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 10/12/2011] [Accepted: 12/22/2011] [Indexed: 11/26/2022]
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30
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Georgescu D, Roiban L, Ersen O, Ihiawakrim D, Baia L, Simon S. Insights on Ag doped porous TiO2 nanostructures: a comprehensive study of their structural and morphological characteristics. RSC Adv 2012. [DOI: 10.1039/c2ra20568h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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31
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Zhu Y, Hua Z, Zhou J, Wang L, Zhao J, Gong Y, Wu W, Ruan M, Shi J. Hierarchical Mesoporous Zeolites: Direct Self-Assembly Synthesis in a Conventional Surfactant Solution by Kinetic Control over the Zeolite Seed Formation. Chemistry 2011; 17:14618-27. [DOI: 10.1002/chem.201101401] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2011] [Revised: 08/08/2011] [Indexed: 11/09/2022]
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32
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Batenburg KJ, Sijbers J. DART: a practical reconstruction algorithm for discrete tomography. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2011; 20:2542-2553. [PMID: 21435983 DOI: 10.1109/tip.2011.2131661] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this paper, we present an iterative reconstruction algorithm for discrete tomography, called discrete algebraic reconstruction technique (DART). DART can be applied if the scanned object is known to consist of only a few different compositions, each corresponding to a constant gray value in the reconstruction. Prior knowledge of the gray values for each of the compositions is exploited to steer the current reconstruction towards a reconstruction that contains only these gray values. Based on experiments with both simulated CT data and experimental μCT data, it is shown that DART is capable of computing more accurate reconstructions from a small number of projection images, or from a small angular range, than alternative methods. It is also shown that DART can deal effectively with noisy projection data and that the algorithm is robust with respect to errors in the estimation of the gray values.
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33
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Batenburg K, van Aarle W, Sijbers J. A semi-automatic algorithm for grey level estimation in tomography. Pattern Recognit Lett 2011. [DOI: 10.1016/j.patrec.2010.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sree SP, Dendooven J, Korányi TI, Vanbutsele G, Houthoofd K, Deduytsche D, Detavernier C, Martens JA. Aluminium atomic layer deposition applied to mesoporous zeolites for acid catalytic activity enhancement. Catal Sci Technol 2011. [DOI: 10.1039/c0cy00056f] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Sree SP, Dendooven J, Smeets D, Deduytsche D, Aerts A, Vanstreels K, Baklanov MR, Seo JW, Temst K, Vantomme A, Detavernier C, Martens JA. Spacious and mechanically flexible mesoporous silica thin film composed of an open network of interlinked nanoslabs. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10270b] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Detavernier C, Dendooven J, Pulinthanathu Sree S, Ludwig KF, Martens JA. Tailoring nanoporous materials by atomic layer deposition. Chem Soc Rev 2011; 40:5242-53. [DOI: 10.1039/c1cs15091j] [Citation(s) in RCA: 302] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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Biermans E, Molina L, Batenburg KJ, Bals S, Van Tendeloo G. Measuring porosity at the nanoscale by quantitative electron tomography. NANO LETTERS 2010; 10:5014-9. [PMID: 21090668 DOI: 10.1021/nl103172r] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Quantitative electron tomography is proposed to characterize porous materials at a nanoscale. To achieve reliable three-dimensional (3D) quantitative information, the influence of missing wedge artifacts and segmentation methods is investigated. We are presenting the "Discrete Algebraic Reconstruction Algorithm" as the most adequate tomography method to measure porosity at the nanoscale. It provides accurate 3D quantitative information, regardless the presence of a missing wedge. As an example, we applied our approach to nanovoids in La2Zr2O7 thin films.
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Affiliation(s)
- E Biermans
- EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
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39
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Beale AM, Jacques SDM, Weckhuysen BM. Chemical imaging of catalytic solids with synchrotron radiation. Chem Soc Rev 2010; 39:4656-72. [PMID: 20978688 DOI: 10.1039/c0cs00089b] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Heterogeneous catalysis is a term normally used to describe a group of catalytic processes, yet it could equally be employed to describe the catalytic solid itself. A better understanding of the chemical and structural variation within such materials is thus a pre-requisite for the rationalising of structure-function relationships and ultimately to the design of new, more sustainable catalytic processes. The past 20 years has witnessed marked improvements in technologies required for analytical measurements at synchrotron sources, including higher photon brightness, nano-focusing, rapid, high resolution data acquisition and in the handling of large volumes of data. It is now possible to image materials using the entire synchrotron radiative profile, thus heralding a new era of in situ/operando measurements of catalytic solids. In this tutorial review we discuss the recent work in this exciting new research area and finally conclude with a future outlook on what will be possible/challenging to measure in the not-too-distant future.
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Affiliation(s)
- Andrew M Beale
- Inorganic Chemistry and Catalysis, Debye Institute for NanoMaterials Science, Sorbonnelaan 16, 3584 CA, Utrecht, The Netherlands.
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Batenburg KJ, Sijbers J, Poulsen HF, Knudsen E. DART: a robust algorithm for fast reconstruction of three-dimensional grain maps. J Appl Crystallogr 2010. [DOI: 10.1107/s0021889810034114] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A novel algorithm is introduced for fast and nondestructive reconstruction of grain maps from X-ray diffraction data. The discrete algebraic reconstruction technique (DART) takes advantage of the intrinsic discrete nature of grain maps, while being based on iterative algebraic methods known from classical tomography. To test the properties of the algorithm, three-dimensional X-ray diffraction microscopy data are simulated and reconstructed with DART as well as by a conventional iterative technique, namely SIRT (simultaneous iterative reconstruction technique). For 100 × 100 pixel reconstructions and moderate noise levels, DART is shown to generate essentially perfect two-dimensional grain maps for as few as three projections per grain with running times on a PC in the range of less than a second. This is seen as opening up the possibility for fast reconstructions in connection within situstudies.
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Ke X, Bals S, Cott D, Hantschel T, Bender H, Van Tendeloo G. Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2010; 16:210-217. [PMID: 20187989 DOI: 10.1017/s1431927609991371] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of +/-90 degrees , which means that the so-called "missing wedge" is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies.
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