Review
Chemistry, Multidisciplinary
Haofei Zhao, Yuchen Zhu, Huanyu Ye, Yang He, Hao Li, Yifei Sun, Feng Yang, Rongming Wang
Summary: Nanocrystals play a crucial role in material sciences and industry. Designing nanocrystals with desired structures and properties is a major challenge that requires a deep understanding of atomic-scale dynamics. In situ transmission electron microscopy (TEM), especially environmental TEM, has provided valuable insights into nanocrystals. This comprehensive review highlights the progress in the understanding of nanocrystal dynamics, including nucleation and growth, structure evolution, and dynamics in reaction conditions.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Jhih H. Liang, Zac Milne, Mehdi Rouhani, Yi-Pan Lin, Rodrigo A. Bernal, Takaaki Sato, Robert W. Carpick, Yeau R. Jeng
Summary: This study presents the first in situ transmission electron microscope (TEM) investigation of diamond-like carbon (DLC) sliding on diamond. The tribological properties of amorphous carbon (a-C) are explored under the harsh condition of sliding against diamond in a vacuum. Real-time TEM imaging provides insights into wear mechanisms and damage. The study reveals that high contact stresses lead to increased adhesion and accelerated wear of a-C on diamond.
Review
Chemistry, Physical
Han-Wen Cheng, Shan Wang, Guanyu Chen, Zhengwang Liu, Dominic Caracciolo, Merry Madiou, Shiyao Shan, Jincang Zhang, Heyong He, Renchao Che, Chuan-Jian Zhong
Summary: This review emphasizes the latest insights into heterogeneous catalysts under relevant reaction conditions using in situ/operando transmission electron microscopic techniques. By discussing atomic-scale and nanoscale details, it highlights the challenges and opportunities in terms of catalytic properties and design applications.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Angela Strass-Eifert, Thomas L. Sheppard, Christian D. Damsgaard, Jan-Dierk Grunwaldt, Robert Guttel
Summary: Designing stable materials for harsh reaction conditions is challenging in catalysis, but HZSM-5 supported cobalt catalysts with encapsulated or exterior cobalt nanoparticles show resistance to sintering even after prolonged operation under CO hydrogenation conditions. In situ environmental TEM experiments demonstrate the high sintering resistance of cobalt nanoparticles up to 700°C, indicating the potential for preparing sinter-stable catalysts for harsh reaction environments.
Article
Chemistry, Physical
Ziqiang Qin, Elizabeth Barsotti, Mohammad Piri
Summary: In this study, new insights into wettability were gained through in situ high-resolution observations, including the fluid-solid occupancies and the physics-based interpretation of sub-nanometer-scale contact angles. Experimental findings revealed density differences between adsorbed wetting film and bulk wetting phase, while discussing the differences between apparent and sub-nanometer contact angles.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Physical
Tobias Meyer, Birte Kressdorf, Vladimir Roddatis, Jorg Hoffmann, Christian Jooss, Michael Seibt
Summary: The study investigates the rich phase diagram of Pr1-xCaxMnO3 and the structural transition in epitaxial thin films, highlighting the importance of controlling the environment during heating.
Article
Materials Science, Multidisciplinary
A. Veverkova, P. Harcuba, J. Vesely, P. Barriobero-Vila, P. Dolezal, J. Pospisil, K. Bartha, J. Smilauerova, J. Kozlik, J. Strasky, M. Janecek
Summary: Phase transformations in a metastable beta Zr-12Nb alloy were investigated using high-energy X-ray diffraction (HEXRD) and complementary in-situ methods. Two bcc phases, l3Zr and l3Nb, were observed in the temperature range studied. The formation of l3Nb phase starts at about 300 degrees C, gradually replacing the original l3Zr phase. Ex-situ observations revealed a cuboidal shape of the u particles and the dissolution of u particles followed by the growth of the a phase at 560 degrees C.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
F. Vogel, S. Ngai, X. Y. Zhou, E. Zaiser, A. M. Manzoni, Y. Wu, W. W. Zheng, P. Zhang, G. B. Thompson
Summary: The study investigates the hierarchical phase separation behavior and microstructural evolution of a single crystal Fe79.5Si15.5V5.0 alloy using transmission electron microscopy (TEM) and atom probe tomography (APT). A complex maze-like microstructure is formed, and the supersaturation in precipitates with Fe and V drives the formation of plates. The study also explores the potential for improving the properties of high-temperature structural materials through the stabilization of hierarchical microstructures.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Yi-Chi Wang, Thomas J. A. Slater, Gerard M. Leteba, Candace I. Lang, Zhong Lin Wang, Sarah J. Haigh
Summary: Tailoring the composition and morphology of nanoparticles is crucial for improving their catalytic performance. This study presents an in situ 3D imaging methodology using single particle reconstruction (SPR) that allows for the investigation of structural transformations and elemental redistribution in nanoparticles. The methodology is applied to study the restructuring of PtNi nanoparticles at elevated temperatures and reveals a transition from a disordered to an ordered phase. The changes in structure and elemental distribution are correlated with a decrease in catalytic activity. This in situ SPR methodology can be extended to study nanoparticle evolution in various environments.
Article
Chemistry, Physical
Xing Li, Shaobo Cheng, Yanghua He, Lixiang Qian, Dmitri Zakharov, Gang Wu, Chongxin Shan, Liang Zhang, Dong Su
Summary: This study investigates the formation and segregation behaviors of Pt-Co alloyed nanoparticles using in-situ environmental transmission electron microscopy. It is found that the formation of Pt-Co nanoparticles occurs consecutively through particle migration coalescence and the Ostwald ripening process. The presence of Pt nanoparticles affects the migration of Co nanoparticles. Theoretical calculations uncover the correlations between the composition and migration of Pt and Co during the ripening process. The findings of this study have important implications for the design, synthesis, and durability of Pt-based nanocatalysts.
Article
Chemistry, Physical
Xing Li, Shaobo Cheng, Yanghua He, Lixiang Qian, Dmitri Zakharov, Gang Wu, Chongxin Shan, Liang Zhang, Dong Su
Summary: This study investigates the formation dynamics and segregation behaviors of Pt-Co alloyed nanoparticles during thermal treatment through in-situ environmental transmission electron microscopy. The research uncovers the complex alloying processes and surface faceting phenomena under oxidation environment, providing fundamental understanding for the design, synthesis, and durability of Pt-based nanocatalysts.
Article
Chemistry, Physical
Alexi L. Pauls, Michael T. Y. Paul, Rana Faryad Ali, Byron D. Gates
Summary: This study analyzed the hydrated form of nickel electrocatalysts prepared by electrochemical aging under alkaline conditions. It was found that the surfaces of aged Ni electrocatalysts contained an electrochemically active layer with predominantly nanocrystalline beta nickel hydroxide. The formation of this gel-like layer has implications for dynamic processes taking place at their interface with the electrolyte, affecting diffusion rates, O-2 bubble nucleation, and bubble release mechanics.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Maanas Togaru, Rajat Sainju, Lichun Zhang, Weilin Jiang, Yuanyuan Zhu
Summary: This study used in situ environmental transmission electron microscopy (ETEM) to investigate the thermal oxidation of pristine and self-ion irradiated polycrystalline tungsten for the first time. Two distinctive tungsten oxide microstructures were observed, showing sensitivity to tungsten surface orientation and dynamic changes during oxidation. The study highlights the importance of surface orientation in influencing the microstructure and oxidation kinetics of tungsten oxide scales.
MATERIALS CHARACTERIZATION
(2021)
Article
Chemistry, Multidisciplinary
Zhirong Zhang, Chen Feng, Xiangyang Li, Chunxiao Liu, Dongdi Wang, Rui Si, Jinlong Yang, Shiming Zhou, Jie Zeng
Summary: A single-atom iron catalyst with in-situ generated Fe4+ centers has been shown to have high activity towards the Oxygen Evolution Reaction (OER), requiring a low overpotential and exhibiting comparable performance to transitional-metal based catalysts. The strong interaction between atomic Fe and carbon support via C-O-Fe bonding was found to be the key factor in lowering the energy barrier for the rate-limiting step of *OOH formation during OER.
Article
Chemistry, Multidisciplinary
Zahra Abdi, Robabeh Bagheri, Mohammad Reza Mohammadi, Zhenlun Song, Mikaela Gorlin, Holger Dau, Mohammad Mahdi Najafpour
Summary: The study presents a new and promising strategy for in situ catalyst synthesis by adding Mn-II to CAN or KMnO4/CAN solution to form Mn-based catalysts for OER. Characterization of the catalysts revealed nano-sized particles catalyzing OER in the presence of CAN. The turnover frequencies for both catalysts were found to be 0.02 (mmolO2 /mol(Mn) • s).
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Niklas A. Weber, Hendrik Schmidt, Tim Sievert, Christian Jooss, Friedrich Guethoff, Vasily Moshneaga, Konrad Samwer, Matthias Krueger, Cynthia A. Volkert
Summary: This study investigates the mechanism of friction at sliding contacts, proposing that friction can be explained by considering the damping of stick-slip pulses. The findings provide a basis for reconciling controversies in literature studies on friction and suggest possible tactics for controlling friction.
Article
Biochemical Research Methods
Zbigniew Zawada, Zijian Guo, Bruno L. Oliveira, Claudio D. Navo, He Li, Pedro M. S. D. Cal, Francisco Corzana, Gonzalo Jimenez-Oses, Goncalo J. L. Bernardes
Summary: This study reports the development of potassium arylethynyltrifluoroborates as unstrained dienophiles for fast, chemically triggered IEDDA reactions, which were applied to protein labeling and enabled mutually orthogonal labeling of two distinct proteins.
BIOCONJUGATE CHEMISTRY
(2021)
Article
Thermodynamics
Julia Zinsmeister, Nina Gaiser, Jens Melder, Thomas Bierkandt, Patrick Hemberger, Tina Kasper, Manfred Aigner, Markus Koehler, Patrick Osswald
Summary: Recent progress in molecular combustion chemistry enables detailed investigation of the intermediate species pool in complex technical fuels. This study provides a comprehensive investigation of complex alternative gasoline fuels using molecular-beam sampling techniques in laminar flow reactors. The ionization techniques used enable deeper mechanistic insights into the reaction network relevant for technical fuels.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Multidisciplinary
Mona Christin Maass, Alexander Tasch, Christian Jooss, Thomas Waitz
Summary: This article presents an experiment on photocatalytic hydrogen production using LED irradiation, which is safer, more environmentally friendly, and suitable for school laboratories or chemistry classes, fostering students' digital competences.
JOURNAL OF CHEMICAL EDUCATION
(2022)
Article
Biochemical Research Methods
Marco Pritzi, Tobias F. Pascher, Marie-Luise Grutza, Philipp Kurz, Milan Oncak, Martin K. Beyer
Summary: Molybdenum sulfides are a promising and inexpensive substitute for platinum catalysts. Through gas-phase experiments, we find that the dissociation pathways of halogenated molybdenum sulfides are drastically different from pure molybdenum sulfides, highlighting possible reaction pathways in a catalytic environment.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2022)
Article
Chemistry, Physical
Gaurav Lole, Fatemeh Ebrahimi, Tobias Meyer, Daniel Mierwaldt, Vladimir Roddatis, Janis Geppert, Marcel Risch, Christian Jooss
Summary: In this study, the stability of the (001) surfaces of Pr1-xCaxMnO3 perovskite films with doping of x = 0.1 and x = 0.33 for catalyzing the oxygen evolution reaction (OER) was investigated using electrochemical and environmental transmission electron microscopy (ETEM) studies. The results showed that the Pr1-xCaxMnO3 (PCMO) x = 0.33 system exhibited Mn leaching due to oxygen vacancy formation at the surface, while the PCMO x = 0.1 system showed higher stability. The enhanced stability in the low-doped system was attributed to the modified Mn 3d-O 2p hybridization, i.e., covalence.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Microscopy
J. Lindner, U. Ross, V. Roddatis, Ch. Jooss
Summary: We report on the development of a Langmuir probe to diagnose the dilute plasma state of Ar and He in the differentially pumped volume at the TEM sample position. The applicability of Langmuir type analysis for the identification of plasma parameters is examined through systematic studies. The results reveal cold plasma characteristics.
Article
Chemistry, Physical
Jens Melder, Stefan Mebs, Florian Lessing, Holger Dau, Philipp Kurz
Summary: This study investigates the influence of incorporating different metal cations on the performance of layered manganese oxides in the OER at different pH values. It is found that doping with Ni and Co ions can significantly enhance the catalytic activity and stability under alkaline and neutral conditions.
SUSTAINABLE ENERGY & FUELS
(2022)
Article
Energy & Fuels
Jens Melder, Julia Zinsmeister, Tobias Grein, Sophie Juergens, Markus Koehler, Patrick Osswald
Summary: This study presents a universal comprehensive two-dimensional gas chromatography method for the analysis of fossil and alternative fuels, allowing for the prediction of combustion properties. The results successfully predicted the sooting behavior of various types of gasoline fuels.
Article
Chemistry, Physical
Marco Pritzi, Tobias F. Pascher, Marie-Luise Grutza, Philipp Kurz, Milan Oncak, Martin K. Beyer
Summary: Molybdenum sulfides and molybdenum oxysulfides are potential and cost-effective alternatives to platinum catalysts for hydrogen evolution reaction (HER). Through collision induced dissociation experiments, stable species [Mo2O2S4]- and [HMo2O2S4]- with potential HER activity are identified.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Emanuel Ronge, Jonas Ohms, Vladimir Roddatis, Travis Jones, Frederic Sulzmann, Axel Knop-Gericke, Robert Schloegl, Philipp Kurz, Christian Jooss, Katarzyna Skorupska
Summary: Investigation of the interaction between a well-established Ca-birnessite catalyst material and an aqueous potassium phosphate buffer electrolyte revealed that the Ca-birnessite electrodes exhibited highly stable oxygen evolution activity in the phosphate buffer. The study suggests that HnPO4(3-n)- anions are incorporated into the catalyst material, acting as stabilizing units for the highly active Mn3+ centers and as internal bases for protons released during the water-oxidation reaction. This unique relationship between (hydrogen)phosphates and Ca-birnessites may play a key role in enhancing catalytic performance in electrocatalytic water oxidation.
SUSTAINABLE ENERGY & FUELS
(2021)