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Your search keyword '"Zaluzec, Nestor J."' showing total 388 results
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388 results on '"Zaluzec, Nestor J."'

1. Linking the Dynamic PicoProbe Analytical Electron-Optical Beam Line / Microscope to Supercomputers

Author

Brace, Alexander, Vescovi, Rafael, Chard, Ryan, Saint, Nickolaus D., Ramanathan, Arvind, Zaluzec, Nestor J., and Foster, Ian

Subjects
Computer Science - Distributed, Parallel, and Cluster Computing, Computer Science - Artificial Intelligence
Abstract

The Dynamic PicoProbe at Argonne National Laboratory is undergoing upgrades that will enable it to produce up to 100s of GB of data per day. While this data is highly important for both fundamental science and industrial applications, there is currently limited on-site infrastructure to handle these high-volume data streams. We address this problem by providing a software architecture capable of supporting large-scale data transfers to the neighboring supercomputers at the Argonne Leadership Computing Facility. To prepare for future scientific workflows, we implement two instructive use cases for hyperspectral and spatiotemporal datasets, which include: (i) off-site data transfer, (ii) machine learning/artificial intelligence and traditional data analysis approaches, and (iii) automatic metadata extraction and cataloging of experimental results. This infrastructure supports expected workloads and also provides domain scientists the ability to reinterrogate data from past experiments to yield additional scientific value and derive new insights.

Published
2023

6. Vapor Infiltration Synthesis of Indium Sulfide Magic Size Cluster

Author

Kim, Kihoon, Havenridge, Shana, Zaluzec, Nestor J., Kang, Donghyeon, Jayaweera, Nuwanthaka P., Elam, Jeffrey W., Mulfort, Karen L., Liu, Cong, and Martinson, Alex B. F.

Abstract

The energetically favorable formation of atomically precise clusters, known as magic size clusters, in the solution phase enables a precision nanoscale synthesis with exquisite uniformity. We report the synthesis of magic size clusters via vapor infiltration of atomic layer deposition precursors directly in a polymer thin film. Sequential infiltration of trimethylindium vapor and hydrogen sulfide gas into poly(methyl methacrylate) leads to the formation of clusters with uniform properties consistent with a magic size cluster─In6S6(CH3)6. While an increase in cluster size might be expected with additional sequential infiltration cycles of the reactive In and S precursors, uniform properties consistent with magic size clusters form in multiple polymers under a range of processing conditions. Ultraviolet–visible absorption spectra of In6S6(CH3)6are largely independent of the number of sequential infiltration cycles and exhibit air stability, both of which are attributed to an energetically favorable synthetic pathway that is evaluated with density functional theory.

Published
2024
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9. Ti‐Modified Imogolite Nanotubes as Promising Photocatalyst 1D Nanostructures for H2 Production.

Author

Jimenéz‐Calvo, Pablo, Naciri, Yassine, Sobolewska, Anna, Isaacs, Mark, Zhang, Yu, Leforestier, Amélie, Degrouard, Jéril, Rouzière, Stéphan, Goldmann, Claire, Vantelon, Delphine, Hettler, Simon, Zaluzec, Nestor J., Arenal, Raul, Launois, Pascale, Ghazzal, Mohamed Nawfal, and Paineau, Erwan

Subjects
BAND gaps, CONDUCTION bands, VALENCE bands, HYDROGEN analysis, HYDROGEN production
Abstract

Imogolite nanotubes (INTs) are predicted as a unique 1D material with spatial separation of conduction and valence band edges but their large band gaps have inhibited their use as photocatalysts. The first step toward using these NTs in photocatalysis and exploiting the polarization‐promoted charge separation across their walls is to reduce their band gap. Here, the modification of double‐walled aluminogermanate INTs by incorporation of titanium into the NT walls is explored. The precursor ratio x = [Ti]/([Ge]+[Ti]) is modulated between 0 and 1. Structural and optical properties are determined at different scales and the photocatalytic performance is evaluated for H2 production. Although the incorporation of Ti atoms into the structure remains limited, the optimal condition is found around x = 0.4 for which the resulting NTs reveal a remarkable hydrogen production of ≈1500 µmol g−1 after 5 h for a noble metal‐free photocatalyst, a 65‐fold increase relative to a commercial TiO2‐P25. This is correlated to a lowering of the recombination rate of photogenerated charge carriers for the most active structures. These results confirm the theoretical predictions regarding the potential of modified INTs as photoactive nanoreactors and pave the way for investigating and exploiting their polarization properties for energy applications. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Amplitude Contrast Imaging in High-Resolution Transmission Electron Microscopy of Ferroelectric Superlattice Film

Author

Wen, Jianguo, Miller, Dean J., Zaluzec, Nestor J., Cook, Russell E., Lee, Ho Nyung, and Wu, Xifan

Subjects
Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
Abstract

To date, high-resolution electron microscopy has largely relied on using the phase of the exit wave function at the exit surface to form a high-resolution electron microscopic image. We have for the first time used chromatic aberration correction to implement a new imaging mode to achieve amplitude contrast imaging in high-resolution electron microscopy, allowing us to obtain directly interpretable high-resolution electron microscopic images with discrimination between light and heavy atomic columns. Using this imaging approach, we have successfully visualized the atomic structure in a BaTiO3/CaTiO3 superlattice with high spatial accuracy and discrimination between Ba and Ca columns, providing direct visualization of the Ca and Ba associated oxygen octahedral tilt that controls ferroelectric behavior in these superlattice structures. Furthermore, this approach offers new opportunities to unravel the structure in a wide range of materials, especially complex oxides with exotic behaviors based on specific structural arrangements., Comment: 20 pages, 5 figures

Published
2014

14. Ti‐Modified Imogolite Nanotubes as Promising Photocatalyst 1D Nanostructures for H2 Production

Author

Jimenéz‐Calvo, Pablo, primary, Naciri, Yassine, additional, Sobolewska, Anna, additional, Isaacs, Mark, additional, Zhang, Yu, additional, Leforestier, Amélie, additional, Degrouard, Jéril, additional, Rouzière, Stéphan, additional, Goldmann, Claire, additional, Vantelon, Delphine, additional, Hettler, Simon, additional, Zaluzec, Nestor J., additional, Arenal, Raul, additional, Launois, Pascale, additional, Ghazzal, Mohamed Nawfal, additional, and Paineau, Erwan, additional

Published
2023
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27. Lithium-Ion Battery Materials as Tunable, “Redox Non-Innocent” Catalyst Supports

Author

Chapovetsky, Alon, primary, Kennedy, Robert M., additional, Witzke, Ryan, additional, Wegener, Evan C., additional, Dogan, Fulya, additional, Patel, Prajay, additional, Ferrandon, Magali, additional, Niklas, Jens, additional, Poluektov, Oleg G., additional, Rui, Ning, additional, Senanayake, Sanjaya D., additional, Rodriguez, José A., additional, Zaluzec, Nestor J., additional, Yu, Lei, additional, Wen, Jianguo, additional, Johnson, Christopher, additional, Jenks, Cynthia J., additional, Kropf, A. Jeremy, additional, Liu, Cong, additional, Delferro, Massimiliano, additional, and Kaphan, David M., additional

Published
2022
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33. Advanced Materials for Energy-Water Systems: The Central Role of Water/Solid Interfaces in Adsorption, Reactivity, and Transport

Author

Barry, Edward, primary, Burns, Raelyn, additional, Chen, Wei, additional, De Hoe, Guilhem X., additional, De Oca, Joan Manuel Montes, additional, de Pablo, Juan J., additional, Dombrowski, James, additional, Elam, Jeffrey W., additional, Felts, Alanna M., additional, Galli, Giulia, additional, Hack, John, additional, He, Qiming, additional, He, Xiang, additional, Hoenig, Eli, additional, Iscen, Aysenur, additional, Kash, Benjamin, additional, Kung, Harold H., additional, Lewis, Nicholas H. C., additional, Liu, Chong, additional, Ma, Xinyou, additional, Mane, Anil, additional, Martinson, Alex B. F., additional, Mulfort, Karen L., additional, Murphy, Julia, additional, Mølhave, Kristian, additional, Nealey, Paul, additional, Qiao, Yijun, additional, Rozyyev, Vepa, additional, Schatz, George C., additional, Sibener, Steven J., additional, Talapin, Dmitri, additional, Tiede, David M., additional, Tirrell, Matthew V., additional, Tokmakoff, Andrei, additional, Voth, Gregory A., additional, Wang, Zhongyang, additional, Ye, Zifan, additional, Yesibolati, Murat, additional, Zaluzec, Nestor J., additional, and Darling, Seth B., additional

Published
2021
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34. Advanced Materials for Energy-Water Systems: The Central Role of Water/Solid Interfaces in Adsorption, Reactivity, and Transport

Author

Barry, Edward, Burns, Raelyn, Chen, Wei, De Hoe, Guilhem X., De Oca, Joan Manuel Montes, De Pablo, Juan J., Dombrowski, James, Elam, Jeffrey W., Felts, Alanna M., Galli, Giulia, Hack, John, He, Qiming, He, Xiang, Hoenig, Eli, Iscen, Aysenur, Kash, Benjamin, Kung, Harold H., Lewis, Nicholas H.C., Liu, Chong, Ma, Xinyou, Mane, Anil, Martinson, Alex B.F., Mulfort, Karen L., Murphy, Julia, Mølhave, Kristian, Nealey, Paul, Qiao, Yijun, Rozyyev, Vepa, Schatz, George C., Sibener, Steven J., Talapin, Dmitri, Tiede, David M., Tirrell, Matthew V., Tokmakoff, Andrei, Voth, Gregory A., Wang, Zhongyang, Ye, Zifan, Yesibolati, Murat, Zaluzec, Nestor J., Darling, Seth B., Barry, Edward, Burns, Raelyn, Chen, Wei, De Hoe, Guilhem X., De Oca, Joan Manuel Montes, De Pablo, Juan J., Dombrowski, James, Elam, Jeffrey W., Felts, Alanna M., Galli, Giulia, Hack, John, He, Qiming, He, Xiang, Hoenig, Eli, Iscen, Aysenur, Kash, Benjamin, Kung, Harold H., Lewis, Nicholas H.C., Liu, Chong, Ma, Xinyou, Mane, Anil, Martinson, Alex B.F., Mulfort, Karen L., Murphy, Julia, Mølhave, Kristian, Nealey, Paul, Qiao, Yijun, Rozyyev, Vepa, Schatz, George C., Sibener, Steven J., Talapin, Dmitri, Tiede, David M., Tirrell, Matthew V., Tokmakoff, Andrei, Voth, Gregory A., Wang, Zhongyang, Ye, Zifan, Yesibolati, Murat, Zaluzec, Nestor J., and Darling, Seth B.

Abstract

The structure, chemistry, and charge of interfaces between materials and aqueous fluids play a central role in determining properties and performance of numerous water systems. Sensors, membranes, sorbents, and heterogeneous catalysts almost uniformly rely on specific interactions between their surfaces and components dissolved or suspended in the water - and often the water molecules themselves - to detect and mitigate contaminants. Deleterious processes in these systems such as fouling, scaling (inorganic deposits), and corrosion are also governed by interfacial phenomena. Despite the importance of these interfaces, much remains to be learned about their multiscale interactions. Developing a deeper understanding of the molecular- and mesoscale phenomena at water/solid interfaces will be essential to driving innovation to address grand challenges in supplying sufficient fit-for-purpose water in the future. In this Review, we examine the current state of knowledge surrounding adsorption, reactivity, and transport in several key classes of water/solid interfaces, drawing on a synergistic combination of theory, simulation, and experiments, and provide an outlook for prioritizing strategic research directions.

Published
2021

37. Ion irradiation of the Ti[O.sub.2] polymorphs and cassiterite

Author

Lumpkin, Gregory R., Blackford, Mark G., Smith, Katherine L., Whittle, Karl R., Zaluzec, Nestor J., Ryan, Edward A., and Baldo, Pete

Subjects
Ion bombardment -- Usage, Polymorphism (Crystallography) -- Research, Tin ores -- Properties, Earth sciences
Abstract

Thin crystals of rutile, brookite, anatase, and cassiterite were irradiated in situ in the transmission electron microscope using 1.0 MeV Kr ions at 50-300 K. Synthetic rutile and natural cassiterite, with 0.1-0.2 wt% impurities, remain crystalline up to a fluence of 5 x [10.sup.15] ions [cm.sup.-2] without evidence for amorphization at 50 K. Natural brookite and anatase, with 0.3-0.5 wt% impurities, become amorphous at fluences of 8.1 x [10.sup.14] and 2.3 x [10.sup.14] ions [cm.sup.-2], respectively. We have also studied two natural rutile samples containing ~1.7 and 1.2 wt% impurities. These samples became amorphous at 9.2 x [10.sup.14] and 8.6 x [10.sup.14] ions [cm.sup.-2] at 50 K, respectively. Further analyses of the fluence-temperature data for natural brookite, rutile, and anatase give critical amorphization temperatures of 168 [+ or -] 11,209 [+ or -] 8, and 242 [+ or -] 6 K, respectively. Results are briefly discussed with respect to several criteria for radiation resistance, including aspects of the structure, bonding, and energetics of defect formation and migration. Keywords: Ti[O.sub.2] polymorphs, anatase, brookite, rutile, cassiterite, ion irradiation, defect migration DOI: 10.2138/am.2010.3329

Published
2010
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39. Electron inelastic mean free path in water

Author

Yesibolati, Murat Nulati, Lagana, Simone, Kadkhodazadeh, Shima, Mikkelsen, Esben Kirk, Sun, Hongyu, Kasama, Takeshi, Hansen, Ole, Zaluzec, Nestor J., Mølhave, Kristian, Yesibolati, Murat Nulati, Lagana, Simone, Kadkhodazadeh, Shima, Mikkelsen, Esben Kirk, Sun, Hongyu, Kasama, Takeshi, Hansen, Ole, Zaluzec, Nestor J., and Mølhave, Kristian

Abstract

Liquid phase transmission electron microscopy (LPTEM) is rapidly developing as a powerful tool for probing processes in liquid environments with close to atomic resolution. Knowledge of the water thickness is needed for reliable interpretation and modelling of analytical studies in LPTEM, and is particularly essential when using thin liquid layers, required for achieving the highest spatial resolutions. The log-ratio method in electron energy-loss spectroscopy (EELS) is often applied in TEM to quantify the sample thickness, which is measured relative to the inelastic mean free path (λIMFP). However, λIMFP itself is dependent on sample material, the electron energy, and the convergence and divergence angles of the microscope electronoptics. Here, we present a detailed quantitative analysis of the λIMFP of water as functions of the EELS collection angle (β) at 120 keV and 300 keV in a novel nanochannel liquid cell. We observe good agreement with earlier studies conducted on ice, but find that the most widely used theoretical models significantly underestimate λIMFP of water. We determine an adjusted average energy-loss term Em, water, and characteristic scattering angle θE, water that improve the accuracy. The results provide a comprehensive knowledge of the λIMFP of water (or ice) for reliable interpretation and quantification of observations in LPTEM and cryo-TEM studies.

Published
2020

45. Electron inelastic mean free path in water

Author

Yesibolati, Murat Nulati, primary, Laganá, Simone, additional, Kadkhodazadeh, Shima, additional, Mikkelsen, Esben Kirk, additional, Sun, Hongyu, additional, Kasama, Takeshi, additional, Hansen, Ole, additional, Zaluzec, Nestor J., additional, and Mølhave, Kristian, additional

Published
2020
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47. In Situ Industrial Bimetallic Catalyst Characterization using Scanning Transmission Electron Microscopy and X‐ray Absorption Spectroscopy at One Atmosphere and Elevated Temperature

Author

Prestat, Eric, Kulzick, Matthew A., Dietrich, Paul J., Smith, Mr. Matthew, Tien, Mr. Eu‐Pin, Burke, M. Grace, Haigh, Sarah J., and Zaluzec, Nestor J.

Subjects
electron microscopy, Communication, energy dispersive X-ray spectroscopy, X-ray absorption spectroscopy, nanoparticles, supported catalysts, Communications
Abstract

We have developed a new experimental platform for in situ scanning transmission electron microscope (STEM) energy dispersive X‐ray spectroscopy (EDS) which allows real time, nanoscale, elemental and structural changes to be studied at elevated temperature (up to 1000 °C) and pressure (up to 1 atm). Here we demonstrate the first application of this approach to understand complex structural changes occurring during reduction of a bimetallic catalyst, PdCu supported on TiO2, synthesized by wet impregnation. We reveal a heterogeneous evolution of nanoparticle size, distribution, and composition with large differences in reduction behavior for the two metals. We show that the data obtained is complementary to in situ STEM electron energy loss spectroscopy (EELS) and when combined with in situ X‐ray absorption spectroscopy (XAS) allows correlation of bulk chemical state with nanoscale changes in elemental distribution during reduction, facilitating new understanding of the catalytic behavior for this important class of materials.

Published
2017

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