Article
Chemistry, Physical
Shichang Xu, Yanjie Zhang, Xiuping Wu, Jinlong Wang, Bing Li, Jingjie Yu
Summary: The red@green core-shell emitting phosphor with monodisperse luminescence center was successfully constructed using a deposition-precipitation (DP) method, showing dual emission features under near-ultraviolet (NUV) excitation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Electrochemistry
Walter Cistjakov, Vincent Laue, Fridolin Roeder, Ulrike Krewer
Summary: All-solid state lithium polymer batteries offer high safety and energy density, and their success depends on an improved design of cathode manufacturing process. A model-based analysis was conducted to study the impact of cathode particle structure on electrochemical cell performance. The study found that the formation of large agglomerates during production of solid-state cathodes significantly affects transport properties.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Bastian Haehnle, Philipp A. Schuster, Lisa Chen, Alexander J. C. Kuehne
Summary: A synthetic toolbox has been developed to create monodisperse core-shell and core-shell-shell particles composed entirely of different types of conjugated polymers. Seeded and fed-batch dispersion polymerizations based on Suzuki-Miyaura-type cross-coupling allow precise control over the interface between conjugated polymer phases, facilitating control over energy transfer phenomena. This new approach offers synthetic freedom for fine-tuning the optical properties of CPP, potentially enabling the synthesis of individual white light-emitting particles.
Article
Optics
Y. F. Chen, D. Li, Y. M. Lee, C. C. Lee, H. Y. Huang, C. H. Tsou, H. C. Liang
Summary: The new output coupler significantly improves the output power and efficiency of the laser, with the double-sided coating effectively increasing the cavity reflectivity. This results in a conversion efficiency of 26.3% for the yellow laser and an output power of 7.0 W for the orange laser, representing a significant enhancement in performance.
Article
Materials Science, Multidisciplinary
Qiliang Zhu, Fan Ye, Wei Yan, Jingrun Zhu, Jianhua Shen, Kan-Hao Xue, Yihua Zhu, Chunzhong Li
Summary: A surface reconstruction strategy is used to synthesize CsPbBr3/CsPb2Br5 core/shell nanocrystals with a uniform coating structure, which exhibit excellent optoelectronic properties and good stability. The core/shell structure is characterized at the atomic scale, and the binding energy between the CsPb2Br5 (116) facet and the CsPbBr3 (100) facet is revealed by density functional theory calculations. The prepared core/shell perovskite nanocrystals can maintain photoluminescence emission after >30 days in water.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Rachel Cherry, Joseph Joel Muhanga, Hamed Mehrabi, Samuel K. Conlin, Robert H. Coridan
Summary: Nanostructured dielectric overlayers can enhance light absorption in nanometer-thin films for optoelectronic applications. By self-assembling a monolayer of polystyrene nanospheres, a core-shell polystyrene-TiO2 structure is grown at temperatures below the polystyrene glass-transition temperature using atomic layer deposition. This tailor-made nanostructured overlayer can significantly increase light absorption in thin film light absorbers.
Article
Chemistry, Applied
Richard Fiedler, Bastian Beizinger, Paul Walther, Mika Lind
Summary: Superparamagnetic iron oxide nanoparticles, particularly in the form of nanoscopic aggregates, have various applications in contrast agents, biological tools, and sensors. The particle size and refractive index can be modified by coating the nanoparticles with another oxide, typically silica. Additionally, introducing mesoporous silica layers enables the nanoparticles to serve as theranostic nanoparticles and high-capacity adsorbers, as well as colorimetric sensors.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Yifan Chen, Xun Zhan, Sandra L. A. Bueno, Ibrahim H. Shafei, Hannah M. Ashberry, Kaustav Chatterjee, Lin Xu, Yawen Tang, Sara E. Skrabalak
Summary: A new method for converting core@shell NPs into HEA NPs through annealing was reported, showing potential for high-quality HEA NPs synthesis. By seed-mediated co-reduction, PdCu@PtNiCo NPs were prepared, which were then converted into singlecrystalline and single-phase PdCuPtNiCo NPs through annealing.
NANOSCALE HORIZONS
(2021)
Article
Chemistry, Multidisciplinary
Fenglei Shi, Jiaheng Peng, Fan Li, Ningkang Qian, Hao Shan, Peng Tao, Chengyi Song, Wen Shang, Tao Deng, Hui Zhang, Jianbo Wu
Summary: In this study, an optimized nanocube with enhanced corrosion resistance was designed based on in-situ study on nanoscale corrosion kinetics. The modified nanocube (MNC) showed the best stability performance in practical electrochemical stability testing, with a minimal loss in specific and mass activity after accelerated durability test. This work highlights the importance of in-situ study in guiding the design of materials with improved properties for practical applications.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Physical
Jinhe Wei, Fei Hu, Xiong Shen, Bingkun Chen, Lin Chen, Zhongming Wang, Chenglong Lv, Qiuyun Ouyang
Summary: The vertically oriented NiCo2S4/MnO2 core-shell nanocomposites, activated by oxygen vacancy engineering, show enhanced electrochemical performance. The hierarchical core-shell nanostructures increase conductivity and provide redox chemical reactions. The NiCo2S4/MnO2-60 electrode delivers appreciable areal capacity and rate capability, and can be used in solid-state hybrid supercapacitors with high energy density and cyclic stability.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Physical
Yuliya Mindarava, Remi Blinder, Valery A. Davydov, Mustapha Zaghrioui, Viatcheslav N. Agafonov, Cecile Autret, Priyadharshini Balasubramanian, Raul Gonzalez Brouwer, Fedor Jelezko
Summary: The article demonstrates the synthesis of core-shell diamond nanoparticles with nitrogen-vacancy centers and naturally abundant C-13 in the core and highly isotopically enriched shell. The particles were formed by overgrowth on previously electron-irradiated nanodiamonds under high-pressure high-temperature conditions. The research showed promising potential for these particles in transferring spin polarization and hyperpolarization of nuclear spins in a fluid environment.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Yuliya Mindarava, Remi Blinder, Valery A. Davydov, Mustapha Zaghrioui, Viatcheslav N. Agafonov, Cecile Autret, Priyadharshini Balasubramanian, Raul Gonzalez Brouwer, Fedor Jelezko
Summary: This article discusses the synthesis of core-shell diamond nanoparticles with nitrogen-vacancy (NV-) centers and isotopically enriched C-13, formed by overgrowth on previously electron-irradiated nanodiamonds. These particles have potential for hyperpolarizing nuclear spins in fluids.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Optics
Nicola Pellizzi, Alfredo Mazzulla, Pasquale Pagliusi, Gabriella Cipparrone
Summary: The development of efficient and cost-effective micromachines is a challenge for applied and fundamental science. The rotational dynamics of core-shell particles with specific architecture when irradiated by light has been studied, providing important insights for optimizing the design of light controlled micro-objects.
PHOTONICS RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Maria Letizia De Marco, Taizhi Jiang, Jie Fang, Sabrina Lacomme, Yuebing Zheng, Alexandre Baron, Brian A. Korgel, Philippe Barois, Glenna L. Drisko, Cyril Aymonier
Summary: This study demonstrates the synthesis of Mie-resonant core-shell particles with overlapping electric and magnetic dipole resonances in the visible spectrum, allowing for tuning of the relative position and intensity of these resonances. Coating high-index particles with low-index shells coalesces the dipoles while maintaining high scattering efficiency, leading to broadband forward scattering. This synthetic strategy opens up new possibilities for metamaterial fabrication with unprecedented control over visible light manipulation.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Allison Wustrow, Guanglong Huang, Matthew J. McDermott, Daniel O'Nolan, Chia-Hao Liu, Gia Thinh Tran, Brennan C. McBride, Shyam S. Dwaraknath, Karena W. Chapman, Simon J. L. Billinge, Kristin A. Persson, Katsuyo Thornton, James R. Neilson
Summary: The study identified a cooperative effect in solid-state metathesis reactions that involves using alkaline earth metals instead of alkali metals to lower the formation temperature of orthorhombic YMnO3. Experiments showed that by reacting MgMn2O4 and CaMn2O4 with YOCl in a cooperative cometathesis reaction, reaction temperatures can be reduced to 550°C while maintaining phase selectivity. This approach also showed potential in synthesizing other metastable targets such as TbMnO3, ErMnO3, and DyMnO3 with reduced temperatures and preserved reaction selectivity.
CHEMISTRY OF MATERIALS
(2021)
Article
Energy & Fuels
Tianyu Zhu, Hadas Sternlicht, Yang Ha, Chen Fang, Dongye Liu, Benjamin H. H. Savitzky, Xiao Zhao, Yanying Lu, Yanbao Fu, Colin Ophus, Chenhui Zhu, Wanli Yang, Andrew M. M. Minor, Gao Liu
Summary: Electrically conductive polymers with hierarchically ordered structures (HOS) show significant enhancement in charge transport properties and mechanical robustness, making them critical for practical lithium-ion batteries. The conventional design of conductive polymers using bottom-up synthetic approaches and functional group modification has limitations that restrict their scaled synthesis and broad applications. By using simple primary building blocks and thermal processing, we developed conductive polymers with HOS, enabling exceptional cycling performance in lithium-ion batteries.
Article
Nanoscience & Nanotechnology
Alexander Vogel, Alicia Ruiz Caridad, Johanna Nordlander, Martin F. Sarott, Quintin N. Meier, Rolf Erni, Nicola A. Spaldin, Morgan Trassin, Marta D. Rossell
Summary: Recent studies have found that oxygen defects on the surface of improper ferroelectric thin films can result in the loss of ferroelectric response. We investigated hexagonal YMnO3 thin films and discovered that the polarization suppression in thinner films is due to oxygen vacancies. We demonstrated that these vacancies form on the film surfaces to screen the large internal electric field. Furthermore, by modifying the oxygen concentration, we can significantly tune the phase transition temperatures. These findings are expected to be applicable to other ferroelectric oxide films, highlighting the importance of controlling oxygen content and cation oxidation states for successful integration in nanoscale applications.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Materials Science, Multidisciplinary
Colin Ophus
Summary: Scanning Transmission Electron Microscopy (STEM) is a powerful characterization tool in materials science research, allowing examination of materials from functional devices to single atoms. This review outlines various STEM experimental methods, with a focus on quantitative data analysis and simulation enabled by open source software. It aims to introduce both classic and new methods to materials scientists, summarizing recent progress in STEM characterization and discussing strengths, weaknesses, and future directions for quantitative STEM research.
ANNUAL REVIEW OF MATERIALS RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Thomas C. Valenza, Paul Chao, Peter K. Weber, Owen K. Neill, Emmanuelle A. Marquis
Summary: We investigated the oxidation behavior of pure titanium and Ti-0.8 at.% Si in Ar-O2 and O2 at 800 degrees C. The enhanced oxidation resistance of Ti-0.8 at.% Si was attributed to the formation of a continuous Ti5Si3 layer at the oxide-metal interface, which initially reduced outward oxide growth and eliminated inward growth. After the breakdown of the Ti5Si3 layer, the oxide on Ti-0.8 at.% Si became lamellar but remained more compact and possibly slower growing than the oxide on pure titanium.
Article
Nanoscience & Nanotechnology
Jiayuwen Qi, Christian Oberdorfer, Emmanuelle A. Marquis, Wolfgang Windl
Summary: In atom probe tomography (APT), atoms are evaporated from a needle-shaped specimen in high field, and their positions and mass are analyzed to reconstruct a 3D image. However, artifacts in the evaporation map can lead to inaccurate reconstructions. Through a new simulation technique, we show that the misalignment of electrostatic and interatomic forces can result in an accumulation of hit events around certain zones, explaining the origin of the artifacts.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Faruk Okur, Huanyu Zhang, Dogan Tarik Karabay, Konrad Muench, Annapaola Parrilli, Antonia Neels, Walid Dachraoui, Marta D. Rossell, Claudia Cancellieri, Lars P. H. Jeurgens, Kostiantyn V. Kravchyk, Maksym V. Kovalenko
Summary: The formation of cavities at the LLZO/Li interface hinders the further development of Li-garnet solid-state batteries. To address this issue, a method of fabricating porous LLZO membranes is proposed, which not only reduces cavity formation but also increases energy densities. The fabricated porous LLZO membranes exhibit long cycling stability.
ADVANCED ENERGY MATERIALS
(2023)
Article
Physics, Applied
Juhyeok Lee, Moosung Lee, YongKeun Park, Colin Ophus, Yongsoo Yang
Summary: Electron tomography provides valuable three-dimensional structural information that cannot be observed by two-dimensional imaging. A new method called multislice electron tomography (MSET) based on four-dimensional scanning transmission electron microscopy (STEM) tilt series is developed to overcome the limitations of the annular dark-field (ADF) STEM-based tomography. The MSET method effectively reduces undesirable reconstruction artifacts and allows precise determination of atomic structures with improved sensitivity for low-Z elements at considerably low electron-dose conditions.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Kevin J. A. Franke, Colin Ophus, Andreas K. Schmid, Christopher H. Marrows
Summary: We used spin-polarized low-energy electron microscopy to study domain pattern transfer in a multiferroic heterostructure consisting of a (111)-oriented BaTiO3 substrate and an epitaxial Ni film. Interfacial strain transfer and inverse magnetostriction induce a uniaxial in-plane magnetic anisotropy that rotates between alternating stripe regions. Two types of magnetic domain walls can be initialized, and the competition between exchange and magnetostatic energies influences the magnetic domain configuration.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Anshul Kamboj, Mukesh N. Bachhav, Megha Dubey, Nathan Almirall, Takuya Yamamoto, Emmanuelle A. Marquis, Robert Odette
Summary: Embrittlement of light water reactor pressure vessel steels by fast neutron irradiation is primarily due to the formation of nanoscale precipitates containing Cu, Ni, Mn, and Si. However, phosphorus (P) also plays a role in embrittlement, with hardening and embrittlement increasing with trace P concentrations in low-Cu steels. Atom probe tomography analysis showed that P and Ni promote precipitation of specific precipitates, which correlates with the observed irradiation hardening.
JOURNAL OF NUCLEAR MATERIALS
(2023)
Article
Multidisciplinary Sciences
Samra Husremovic, Berit H. Goodge, Matthew P. Erodici, Katherine Inzani, Alberto Mier, Stephanie M. Ribet, Karen C. Bustillo, Takashi Taniguchi, Kenji Watanabe, Colin Ophus, Sinead M. Griffin, D. Kwabena Bediako
Summary: In this study, researchers demonstrate high-density phase change memory based on phase transition materials. By fabricating H-TaS2/1T-TaS2 heterostructures, they observe optically active heterochirality and correlate it with resistivity steps in the CDW superlattice structure. They also show the role of strain engineering in promoting multi-level switching.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Sangui Liu, Xinbao Han, Colin Ophus, Shiyuan Zhou, You-Hong Jiang, Yue Sun, Tiqing Zhao, Fei Yang, Meng Gu, Yuan-Zhi Tan, Shi-Gang Sun, Haimei Zheng, Hong-Gang Liao
Summary: When an ionic crystal dissolves in a solvent, the associated positive and negative ions are released. However, the understanding of the form, interaction, and dynamics of ions in real solution is limited due to experimental challenges. Using liquid phase transmission electron microscopy, we observed the diffusion and aggregation of POM ions in water. Real-time observation revealed unexpected local reciprocating hopping motion of ions, possibly due to short-range polymerized bridges of water molecules. Ion oligomers in dilute solution undergo frequent splitting, aggregation, and rearrangement, indicating weak counterion-mediated interaction. Furthermore, POM ions with tetrahedral geometry exhibit directional interaction and structure-dependent dynamics compared to spherical ions.
Article
Materials Science, Multidisciplinary
Kevin J. A. Franke, Colin Ophus, Andreas K. Schmid, Christopher H. Marrows
Summary: We present a study on the transfer of domain patterns from a (111)-oriented ferroelectric BaTiO3 substrate to an epitaxial Co film grown on a Pd buffer layer. The transfer is achieved through interfacial strain transfer and inverse magnetostriction, resulting in stripe regions with modulated in-plane uniaxial magnetic anisotropy direction. The formation of two distinct anisotropy configurations between stripe regions is observed, leading to different angles between adjacent domain magnetizations. The study also explores the initialization of different magnetization configurations by applying a magnetic field parallel or perpendicular to the stripes.
Article
Materials Science, Multidisciplinary
Zixuan Guo, Colin Ophus, Karen C. Bustillo, Ryan Fair, Stefan C. B. Mannsfeld, Alejandro L. Briseno, Enrique D. Gomez
Summary: Organic semiconductor materials have versatile applications in electrical devices such as solar cells and transistors. However, controlling the molecular packing at organic-organic interfaces and characterizing buried interlayer morphology is challenging. In this study, we demonstrate the growth of single-crystalline bilayer organic semiconductors on graphene using two small molecules, ZnPc and PTCDA, through vertical physical vapor transport. We use 4D-scanning transmission electron diffraction (4D-STEM) to directly observe the orientation distribution of ZnPc and PTCDA crystallites on graphene, elucidating different growth mechanisms and predicting the morphology of stacked ZnPc/PTCDA heterojunctions.
MRS COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Bengisu Sari, Steven E. Zeltmann, Chunsong Zhao, Philipp M. Pelz, Ali Javey, Andrew M. Minor, Colin Ophus, Mary C. Scott
Summary: In recent years, there has been a growing interest in 2D non-graphene materials, with tellurium (Te) as a single-element van der Waals semiconductor gaining attention due to its anisotropic physical properties. Combining electron microscopy with image simulations, researchers have determined the precise orientation of Te flakes on a WSe2 substrate and analyzed the resulting moire lattice structure. Additionally, local strain within the Te/WSe2 layered materials was investigated using scanning nanodiffraction techniques.
Article
Materials Science, Multidisciplinary
Tian Liu, Juliane Scholtz, Fei Xue, Audrey Yung, Gilles Guiglionda, Emmanuelle A. Marquis
Summary: This study systematically quantified the clustering behaviors in two Al-Mg-Si alloys and found that the addition of Cu can slow down the natural aging process and reduce the negative effect of post pre-aging natural aging on beta precipitation by changing the composition of the Mg and Si rich clusters.