Article
Chemistry, Physical
Daniel S. Mosiman, Yi-Sheng Chen, Limei Yang, Brian Hawkett, Simon P. Ringer, Benito J. Marinas, Julie M. Cairney
Summary: Two techniques were developed to encapsulate and prepare HAP NPs into APT tips for characterization, revealing significant tradeoffs between encapsulant methods/materials for HAP characterization and the need for further technique development to select a more robust approach. This work serves as an essential starting point for advancing knowledge about the nanoscale spatiochemistry of HAP NPs.
Article
Chemistry, Physical
Yu Xia, Jiaming Liu, Xingchu Zhang, Renlong Zhou
Summary: Research findings show that laser energy absorption and field evaporation mechanisms can be described by an effective cross section, while the fluctuation of charge state is influenced by collective excitation of electrons. The average charge state is only dependent on the static field strength.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Materials Science, Multidisciplinary
Jan P. Josten, Peter J. Felfer
Summary: This work presents a method for lifting out single nanoparticles in the scanning electron microscope, providing compositional and structural insights for nanoparticles and demonstrating segregation in nanorods. The approach allows for analysis of unsupported nanoparticles and produces well-defined structured samples.
MICROSCOPY AND MICROANALYSIS
(2022)
Article
Anatomy & Morphology
Nora Vorlaufer, Jan Josten, Simon Carl, Erik Goebel, Alexander Sogaard, Nicola Taccardi, Erdmann Spiecker, Peter Felfer
Summary: This paper introduces a workflow for preparing atom probe specimens from suspended particles, achieving a near-tip shape geometry without the need for time-consuming FIB lift-out. The method combines dielectrophoresis and electrodeposition to enable a simple and quick preparation process with high throughput. The resulting specimens allow for stable measurements with low fracture rates.
MICROSCOPY RESEARCH AND TECHNIQUE
(2023)
Article
Nanoscience & Nanotechnology
Martin Detrois, Zongrui Pei, Tao Liu, Jonathan D. Poplawsky, Michael C. Gao, Paul D. Jablonski, Jeffrey A. Hawk
Summary: The study found that silicon has a negative impact on the improvement of creep properties in Ni-based superalloys when using B, as silicon decreases the grain boundary cohesion, offsetting the effects of B segregation.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
Tim M. Schwarz, Hongyi Zhan, Baptist Gault, Christopher M. Gourlay, Ingrid McCarroll
Summary: The peak-aged magnesium-aluminum-rare earth (Mg-Al-RE) alloy AE44-2, produced through high-pressure die casting, exhibits a 10% increase in yield strength due to the formation of nanoscale AlMn precipitates. Atom probe tomography reveals the presence of Ce-rich clusters in the dendritic region rather than the inter-dendritic alpha-Mg in the as cast state, indicating their formation is mainly determined by solidification kinetics rather than concentration. These Ce-rich clusters act as heterogeneous nucleation sites for the formation of Al10Mn7RE2 nanoscale precipitates during the T5 heat treatment, suggesting a potential pathway for tailoring mechanical properties.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Colin A. Stewart, Richard W. Fonda, Keith E. Knipling
Summary: An ICME approach was utilized to design a fully Austenitic, Mn-stabilized steel strengthened by nano-scale precipitate phases. Experimental verification confirmed that significant strengthening can be achieved by adding Cu together with Ni+Al, forming FCC-Cu and beta-NiAl nano-precipitates.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
P. Maugis, M. Jouiad, F. Roch, C. Perrin-Pellegrino, K. Hoummada
Summary: Experimental and modeling studies on carbon and nitrogen segregation to dislocations in C-Mn ferritic steels were reported. A model based on McLean theory was established to describe the competitive segregation of carbon and nitrogen in the Cottrell atmospheres around dislocations, taking into account the effect of dislocation density. It was found that the plastic strain during tensile test can modify the material properties by changing the nature and quantity of segregated atoms around dislocations, leading to a preferential segregation of nitrogen over carbon.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Geochemistry & Geophysics
Rick Verberne, Steven M. Reddy, David W. Saxey, Denis Fougerouse, William D. A. Rickard, Zakaria Quadir, Noreen J. Evans, Chris Clark
Summary: Element mobility is crucial in geological processes, and understanding how elements migrate in minerals is essential for geochemical and geochronological applications. This study investigates the trace-element composition of dislocations on twin boundaries in rutile using atom probe tomography and transmission electron microscopy. The findings reveal that dislocations in rutile can act as both fast-diffusion pathways and traps for trace elements.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Physics, Applied
Constantinos Hatzoglou, Benjamin Klaes, Fabien Delaroche, Gerald Da Costa, Brian Geiser, Markus Kuehbach, Peter B. Wells, Francois Vurpillot
Summary: Reconstructions in atom probe tomography are biased by image distortions arising from dynamic changes of the specimen geometry. Current models for understanding and reproducing image artifacts are too slow or not adapted to be routinely used in image correction approaches. To address this, we propose an alternative simulation tool based on a coarse-grained model of the sample surface that accurately reproduces the effects of temperature and electric field on ion projection.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Arjun BalaKrishnan, Niclas Blanc, Ulrich Hagemann, Parham Gemagami, Kevin Wonner, Kristina Tschulik, Tong Li
Summary: The effect of different surface orientations on the formation of iridium oxide species during the oxygen evolution reaction (OER) was studied using a needle-shaped iridium atom probe specimen as a nanosized working electrode. It was found that a thick subsurface oxide layer consisting of sub-stoichiometric Ir-O species on the open (024) planes contributes additional activity to the OER process. This study highlights the importance of surface morphological effects on iridium electrocatalysts for OER and provides a new method to directly reveal surface species on electrocatalysts at the atomic scale.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Chanwon Jung, Biswanath Dutta, Poulumi Dey, Seong-jae Jeon, Seungwoo Han, Hyun-Mo Lee, Jin-Seong Park, Seong-Hoon Yi, Pyuck-Pa Choi
Summary: A novel method of fabricating nanostructured Heusler compounds is proposed by crystallizing an amorphous precursor, resulting in two distinct nanostructures. One of the structures exhibits enhanced negative Seebeck coefficients, potentially due to low energy electron filtering and Co interstitial defects at the interfaces within the nano precipitates. Advanced characterization techniques and theoretical calculations provide detailed insights into the samples.
Article
Microscopy
Jiangtao Qu, Wenjie Yang, Tianhao Wu, Wenhao Ren, Jun Huang, Haijun Yu, Chuan Zhao, Matthew J. Griffith, Rongkun Zheng, Simon P. Ringer, Julie M. Cairney
Summary: This paper demonstrates three effective methods to prepare needle-shaped specimens for atom probe tomography measurements from nanoparticles of different sizes, providing high quality data critical to understanding and controlling the performance of functional nanoparticles. These methods address the challenge of specimen preparation from particle samples for atom probe measurement and expands the application of atom probe tomography.
Review
Engineering, Biomedical
Kathryn Grandfield, Chiara Micheletti, Joseph Deering, Gabriel Arcuri, Tengteng Tang, Brian Langelier
Summary: Biominerals and biomaterials play important roles in our daily lives. Atom probe tomography (APT) is a promising three-dimensional characterization technique that can provide insights into the structures and compositions of biominerals and biomaterials at the nanoscale. APT has the potential to enhance our understanding of biomineralization mechanisms and inform biomaterial design.
ACTA BIOMATERIALIA
(2022)
Article
Chemistry, Multidisciplinary
Mathias Kraemer, Bar Favelukis, Ayman A. El-Zoka, Maxim Sokol, Brian A. Rosen, Noam Eliaz, Se-Ho Kim, Baptiste Gault
Summary: A study reveals the presence of alkali and halogen elements, as well as unetched aluminum in MXenes materials, which are often overlooked when considering the activity and performance.
ADVANCED MATERIALS
(2023)
Article
Physics, Multidisciplinary
Su-Hyun Yoo, Se-Ho Kim, Eric Woods, Baptiste Gault, Mira Todorova, Joerg Neugebauer
Summary: Atom probe tomography (APT) analysis provides near-atomic-scale information on the composition of complex materials. This study combines density-functional theory (DFT) calculations and APT measurements to investigate the origin of hydrogen residuals in APT experiments. The results demonstrate that material-specific physical properties strongly influence the detection of hydrogen residuals, contradicting the hypothesis of direct ionization of residual hydrogen without interaction with the specimen's surface.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
Heena Khanchandani, Ayman A. El-Zoka, Se-Ho Kim, Uwe Tezins, Dirk Vogel, Andreas Sturm, Dierk Raabe, Baptiste Gault, Leigh T. Stephenson
Summary: Numerous metallurgical and materials science applications rely on quantitative atomic-scale characterizations of environmentally-sensitive materials and their transient states. This paper discusses two examples demonstrating the realization of ex-situ thermochemical treatment using a reaction chamber called the Reacthub, and characterizing the treated materials using atom probe or scanning Xe+/electron microscopes.
Article
Chemistry, Physical
Se-Ho Kim, Stoichko Antonov, Xuyang Zhou, Leigh T. Stephenson, Chanwon Jung, Ayman A. El-Zoka, Daniel K. Schreiber, Michele Conroy, Baptiste Gault
Summary: The global development of electric vehicles and energy storage has sparked interest in battery technology, requiring detailed understanding of battery microstructure and chemistry for long-term, sustainable, and safe operation. Atom probe tomography (APT) with sub-nanometre resolution plays a key role in battery research, but faces challenges such as electric field-driven migration and sample preparation. Methods to shield from the electric field and address these challenges are discussed to enable accurate analysis of battery materials.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Robotics
Ue-Hwan Kim, Se-Ho Kim, Jong-Hwan Kim
Summary: This study proposes the SimVODIS++ architecture, which combines neural semantic visual odometry, object detection, and instance segmentation to improve VO performance in dynamic environments. Experimental results demonstrate the effectiveness of SimVODIS++ and the solution to the data leakage problem in the conventional experiment setting.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Se-Ho Kim, Su-Hyun Yoo, Sangyong Shin, Ayman A. El-Zoka, Olga Kasian, Joohyun Lim, Jiwon Jeong, Christina Scheu, Joerg Neugebauer, Hyunjoo Lee, Mira Todorova, Baptiste Gault
Summary: Fuel cells can power cars or houses with no direct carbon emissions by recombining water from H-2 and O-2. Anion-exchange membrane fuel cells (AEMFCs) achieve high power densities by operating at high pH instead of using large volumes of noble metal catalysts. However, the slow kinetics of the hydrogen-oxidation reaction (HOR) limits scaling up.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Se-Ho Kim, Kang Dong, Huan Zhao, Ayman A. El-Zoka, Xuyang Zhou, Eric V. Woods, Finn Giuliani, Ingo Manke, Dierk Raabe, Baptiste Gault
Summary: By using cryo-atom probe tomography, we have discovered the degradation process between the liquid electrolyte and Si electrode. We found that the Si electrode corrodes before the charge-discharge cycles begin, and the delithiation process leads to the formation of nanograins. These nanograins are pulverized into nanoscale fragments that float in the electrolyte. The electrolyte also decomposes during this process. Understanding these microstructures is crucial for understanding the degradation of Si anodes and can potentially inform the design of new batteries.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Chanwon Jung, Hosun Jun, Kyuseon Jang, Se-Ho Kim, Pyuck-Pa Choi
Summary: This study utilizes atom probe tomography to investigate the structure-property relationships of carbon-supported nanoparticles. It synthesizes and analyzes carbon-supported Pt, PtMn alloy, and ordered Pt3Mn nanoparticles as model systems. The research provides insights into the 3D elemental distribution and the field evaporation behavior of the carbon support, and offers guidance for future studies and applications.
MICROSCOPY AND MICROANALYSIS
(2022)
Article
Materials Science, Multidisciplinary
Se-Ho Kim, Leigh T. Stephenson, Alisson K. da Silva, Baptiste Gault, Ayman A. El-Zoka
Summary: This study investigates the phase separation and mixing processes of EGaIn alloy during thermal cycling using cryogenically-enabled advanced microscopy and microanalysis. The results reveal a thermal-stimulus-response behavior of EGaIn at cryogenic temperatures, with a sudden volume expansion associated with the formation of metastable Ga phases. These findings highlight the importance of rejuvenation kinetics and open new possibilities for the application of EGaIn as a self-healing material.
Article
Materials Science, Multidisciplinary
Se-Ho Kim, Leigh T. Stephenson, Torsten Schwarz, Baptiste Gault
Summary: This study compared the distribution of constituent elements in two different smartphone glass samples using X-ray spectroscopy techniques and atom probe tomography (APT). The results demonstrated that APT can be considered as an alternative technique for imaging the chemical distribution in glass for mobile applications.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Physics, Multidisciplinary
Xuyang Zhou, Yang Bai, Ayman A. El-Zoka, Se -Ho Kim, Yan Ma, Christian H. Liebscher, Baptiste Gault, Jaber R. Mianroodi, Gerhard Dehm, Dierk Raabe
Summary: Solid-state redox-driven phase transformations can create pores, and the accumulation of redox products inside the pores can influence the local equilibrium and kinetics of the transformation process. Studying the reduction of iron oxide by hydrogen helps us understand the sluggish reduction process and its significance for sustainable steelmaking.
PHYSICAL REVIEW LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Se-Ho Kim, Kihyun Shin, Xuyang Zhou, Chanwon Jung, Hyun You Kim, Stella Pedrazzini, Michele Conroy, Graeme Henkelman, Baptiste Gault
Summary: Atom probe tomography is a useful technique for obtaining sub-nanoscale information from technologically-relevant materials. However, the analysis of functional ceramics, especially perovskites, remains challenging due to low yield and success rate. This study shows that a metallic coating can prevent charge penetration and suppress the volume change associated with the piezoelectric effect, allowing for successful analysis of BaTiO3 particles in a metallic matrix.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Multidisciplinary
Yan Ma, Jae Wung Bae, Se-Ho Kim, Matic Jovicevic-Klug, Kejiang Li, Dirk Vogel, Dirk Ponge, Michael Rohwerder, Baptiste Gault, Dierk Raabe
Summary: The authors demonstrate a method of sustainable steel production by reducing solid iron oxides with hydrogen released from ammonia. Ammonia, which can be synthesized with green hydrogen and release hydrogen again through the reduction reaction, connects with green iron making as a replacement for fossil reductants. The study shows that ammonia-based reduction of iron oxide is as effective as hydrogen-based direct reduction, and can be implemented industrially with existing technologies.
Article
Chemistry, Physical
Leonardo Shoji Aota, Chanwon Jung, Siyuan Zhang, Se-Ho Kim, Baptiste Gault
Summary: Pd-based electro-catalysts play a crucial role in enhancing the methanol oxidation reaction kinetics in alcohol fuel cells, but their performance degrades over time. Scanning electron microscopy and atom probe tomography were used to investigate the chemical changes at the microstructural/atomic scale responsible for this effect after accelerated degradation tests. No morphological changes were observed after 1000 MOR cycles, but leaching of Pd and B from PdAu nanoparticles and the formation of Au-rich regions on the catalyst's surface were identified. These insights underscore the importance of understanding the chemical modifications during MOR for the design of new catalysts.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Physical
Su-Hyun Yoo, Leonardo Shoji Aota, Sangyong Shin, Ayman A. El-Zoka, Phil Woong Kang, Yonghyuk Lee, Hyunjoo Lee, Se-Ho Kim, Baptiste Gault
Summary: The introduction of interstitial dopants offers a new approach to optimize the catalytic activity of nanoparticles. However, the stability of a property-enhancing dopant (B) introduced in the controlled synthesis of a Pd aerogel electrocatalyst is significantly reduced after the hydrogen oxidation reaction. First-principles calculations suggest that the presence of H on the surface leads to the departure of subsurface B from the Pd nanostructure. This destabilization of subsurface B is more pronounced with increased H occupation of surface and interstitial sites. Thus, H2 fuel itself promotes the microstructural degradation and activity drop of the electrocatalyst.
ACS ENERGY LETTERS
(2023)
Article
Green & Sustainable Science & Technology
Mahander P. P. Singh, Se-Ho Kim, Xuyang Zhou, Hiram Kwak, Alisson Kwiatkowski da Silva, Stoichko Antonov, Leonardo Shoji Aota, Chanwon Jung, Yoon Seok Jung, Baptiste Gault
Summary: This study uses cryogenic atom probe tomography to investigate the surface chemistry changes of cathode materials for Li-ion batteries. The formation of Li2CO3 species on the surface of a LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode material when exposed to air is observed. These findings are crucial for improving cathode synthesis and cell assembly protocols, as well as understanding cathode degradation processes.
ADVANCED ENERGY AND SUSTAINABILITY RESEARCH
(2023)
Article
Microscopy
C. Gao, C. Hofer, T. J. Pennycook
Summary: Ptychography provides high dose efficiency images that can reveal light elements next to heavy atoms. However, contrast reversals can occur when the projected potential becomes strong. Recent research has shown that these reversals can be counteracted by adapting the focus. This study explains why the best contrast is often found with the probe focused to the middle of the sample and highlights the importance of convergence angle in thin samples to remove contrast reversals.
Article
Microscopy
J. Lindner, U. Ross, T. Meyer, V. Boureau, M. Seibt, Ch. Jooss
Summary: Phase-shifting electron holography is an excellent method with high phase sensitivity to reveal electron wave phase information. An advanced drift correction scheme is proposed in this study, which exploits the interface of the TEM specimen and the vacuum area in the hologram. This method allows for obtaining reliable phase information.
Article
Microscopy
Ali Jaberi, Nicolas Brodusch, Jun Song, Raynald Gauvin
Summary: This study investigates knock-on damage in lithium-ion batteries (LIBs) by computing threshold displacement energies (TDEs) and performing Monte Carlo simulation. The results indicate that Li is most sensitive to knock-on damage at moderate electron energies, and TDE is the principal parameter for assessing Li sensitivity to knock-on damage across similar structures.
Article
Microscopy
Alexander Schroeder, Christopher Rathje, Leon van Velzen, Maurits Kelder, Sascha Schaefer
Summary: This study utilizes novel event-based electron detector platforms to extend the temporal resolution of electron microscopy. By training a neural network to predict electron arrival time, the researchers were able to improve the timing accuracy and achieve a promising solution for enhancing electron timing precision in various electron microscopy applications.
Article
Microscopy
Avi Auslender, Nivedita Pandey, Amit Kohn, Oswaldo Dieguez
Summary: This article describes a faster implementation based on DFT for computing the mean inner potential of crystals, providing quantum-mechanical calculations beyond the independent-atom approximation. The study also reveals the dependence of the mean inner potential on sample boundary conditions, mass density, and magnetic susceptibility, highlighting its correlation with various material properties.
Article
Microscopy
Zhidong Yang, Dawei Zang, Hongjia Li, Zhao Zhang, Fa Zhang, Renmin Han
Summary: In this work, we propose a self-supervised deep learning model for cryo-ET volumetric image denoising based on noise modeling and sparsity guidance. Experimental results demonstrate that our method can achieve reliable denoising by training on single noisy volume and outperform existing methods.
Article
Microscopy
J. Kuttruff, J. Holder, Y. Meng, P. Baum
Summary: In this study, a robust clustering algorithm is proposed that can find clusters in a continuous stream of raw data in real time. This algorithm converts pixel hits measured by hybrid pixel detectors to real single-electron events. By continuously comparing with previous hits, the algorithm efficiently identifies the merging of new and old events.
Article
Microscopy
D. G. Senturk, C. P. Yu, A. De Backer, S. Van Aert
Summary: This article presents a statistics-based method for accurately counting the number of atoms in nanostructures, especially for images acquired with low electron doses and multiple element structures.
Article
Microscopy
Mauricio J. Prieto, Lucas de Souza Caldas, Liviu C. Tanase, Thomas Schmidt, Oscar Rodriguez de la Fuente
Summary: This study presents a synchrotron-based investigation of the synthesis process of a magnetite/hematite bilayer. Ion bombardment gradually transforms hematite into magnetite, and the growth of magnetite leads to the formation of stable boundaries. These findings are significant for understanding novel oxide heterostructures.
Article
Microscopy
Emre Yoruk, Holger Klein, Stephanie Kodjikian
Summary: Beam sensitive nanomaterials pose challenges for crystallographic structure determination. A dose symmetric electron diffraction tomography (DS-EDT) method is developed to reduce beam damage and obtain complete data sets by merging individual datasets from multiple crystals.
Article
Microscopy
A. Pofelski, Y. Zhu, G. A. Botton
Summary: The precision and sensitivity of the GPA method for strain characterization is a widely discussed topic. This study introduces the concept of phase noise and analyzes the parameter of sampling to improve the precision of GPA. Experimental and theoretical results demonstrate that using a larger pixel spacing in STEM can enhance the precision and sensitivity of the GPA method.
Article
Microscopy
Sangjun Kang, Di Wang, Christian Kuebel, Xiaoke Mu
Summary: Transmission electron microscopy is a valuable tool for assessing strain fields within materials. However, using thin specimens in TEM analysis can affect atomic configuration and deformation structure.
