Article
Chemistry, Applied
Machi Takeuchi, Tsuyoshi Mashima, Michael Sztucki, Abdrei Petukhov, Mark Vis, Heiner Friedrich, Remco Tuinier
Summary: Phosvitins are important egg yolk proteins found in food emulsions. They have both ion binding and emulsifying abilities and are influenced by pH and ionic strength. Our experiments using SAXS revealed that the interactions between charged phosvitin assemblies are strongly affected by pH and ionic strength. We also found that metal ions can induce the aggregation of phosvitin by electrostatic attraction.
FOOD HYDROCOLLOIDS
(2022)
Article
Multidisciplinary Sciences
Rui Shi, Anthony J. Cooper, Hajime Tanaka
Summary: The behaviour of ions solvated in water is highly ion-specific and can be explained by considering the interplay between ion-water and inter-water interactions as well as the bond-orientational order of the hydration shell. This study provides insight into the ion-specific effects observed in salt solutions and their impact on solution dynamics. The findings have fundamental implications for ionic processes in aqueous solutions, offering a physical principle for electrolyte design and application.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Hikari Watanabe, Nana Arai, Erika Nozaki, Jihae Han, Kenta Fujii, Kazutaka Ikeda, Toshiya Otomo, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe, Yasuo Kameda, Yasuhiro Umebayashi
Summary: The study found that the local structure of Li+ changes with increasing LiTFSA concentration, forming oligomers when the molar fraction of LiTFSA exceeds 0.25. In superconcentrated LiTFSA aqueous solution, the average structure is determined by the coordination of two water molecules and two oxygen atoms of the TFSA anion(s) to Li+.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Chaya Weeraratna, Oleg Kostko, Musahid Ahmed
Summary: In this study, X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy were used to investigate the solvation of NH4NO3. The results indicate that the nitrate anion prefers the surface, while the ammonium and nitrate ions are equally present in the bulk.
Article
Chemistry, Physical
Li Sun
Summary: The individual ionic activity coefficients of chloride salts in aqueous solutions are predicted using the II + IW theory. Two combinations of the II + IW theory, mean spherical approximation plus Born equation, are proposed in this work. Different ion radii are used for calculations. The predicted results are presented and compared with experimental data. The study finds that the II + IW theory can reasonably predict the individual ionic activity coefficients of specific electrolytes in aqueous solutions, and adjusting ion radius can improve the modeling performance.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Physical
Xueling Pan, Qiutian Wang, Zihao Ma, Yao Qin, Xiaohua Lu, Wanqin Jin, Yudan Zhu
Summary: 18-Crown-6 ether has been widely studied for its excellent ionic recognition performance in biomimetic and smart nanomaterials for membrane separation, chemical sensing, and adsorption. However, the specific role of water molecules in ionic recognition by 18-crown-6 ether remains poorly understood. This study used molecular dynamics simulation to investigate the mechanism of water molecules in the ionic recognition performance of 18-crown-6 ether. The results showed that the recognition order of ions followed K+ > Na+ > Li+ > Fe2+ > Mg2+. The presence of Mg2+ enhanced the selectivity of K+ recognition compared to Na+. Detailed analysis revealed that changes in the hydrogen bond network structure of water molecules played a major role in the recognition process.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Sahar Ehsani-Tabar, Abbas Mehrdad, Ali Shayanfar
Summary: The salt effect of sodium chloride, potassium chloride, choline acetate, choline lactate, and choline propionate on ibuprofen in aqueous solutions of 1-propanol was investigated using various methods. It was found that sodium chloride and potassium chloride have a salting-out effect, while choline acetate, choline lactate, and choline propionate have a salting-in effect.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Materials Science, Multidisciplinary
Yuta Ito, Isao Tsuyumoto
Summary: Nanocrystalline lithium niobate, LiNbO3, is prepared through an aqueous solution process, starting from peroxo - polyniobic acid solution. The crystalline LiNbO3 has the same structure as conventional LiNbO3 with a small crystallite size. The nanocrystalline LiNbO3 prepared at 500 degrees Celsius exhibits a high ionic conductivity.
MATERIALS CHEMISTRY AND PHYSICS
(2021)
Article
Chemistry, Physical
Zhuanfang Jing, Yongquan Zhou, Wenqian Zhang, Toshio Yamaguchi, Koji Yoshida, Guangguo Wang, Li Han
Summary: Wide angle X-ray scattering (WAXS) and density functional theory (DFT) were used to study the structures of aqueous 18-crown-6/CsCl solutions. The results showed the formation of strong hydrogen bonds between 18-crown-6 and Cs+. The hydration of the 18-crown-6/Cs+ complex was found to decrease with increasing CsCl concentration in the solution.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Applied
Han-Wei Chang, Yu-Cheng Huang, Jeng-Lung Chen, Chi-Liang Chen, Jin-Ming Chen, Da-Hua Wei, Wu-Ching Chou, Chung-Li Dong, Yu-Chen Tsai
Summary: Electrochemistry and X-ray absorption spectroscopy (XAS) were used to evaluate the capacitive performance and electronic structure of MnO2/reduced graphene oxide (RGO) as a supercapacitor. The specific capacitance of MnO2/RGO increased with the growth time, and the contributions to the capacitance were from electrochemical double-layer capacitance and pseudocapacitance.
Article
Multidisciplinary Sciences
Liwen Jiang, Ke Zhang, Yixin Yao, Shuai Li, Jiao Li, Zhen Tian, Weili Zhang
Summary: This article introduces a new method for analyzing aqueous salt solutions using terahertz optoacoustics. The method manipulates terahertz optoacoustic signals through temperature control to reduce water background and provide more solute information. The results demonstrate the significant potential of this method for distinguishing different salt solutions and quantitatively analyzing salt concentrations.
Article
Chemistry, Multidisciplinary
Steffen Staeck, Anna Andrle, Philipp Hoenicke, Jonas Baumann, Daniel Groetzsch, Jan Weser, Gesa Goetzke, Adrian Jonas, Yves Kayser, Frank Foerste, Ioanna Mantouvalou, Jens Viefhaus, Victor Soltwisch, Holger Stiel, Burkhard Beckhoff, Birgit Kanngiesser
Summary: This article introduces a technique called scan-free grazing-emission X-ray fluorescence spectroscopy (GEXRF) and applies it to the investigation of 2D nanostructures. The experimental results are in good agreement with the simulations, demonstrating the applicability of this method in quality control and process engineering.
Article
Astronomy & Astrophysics
Jiong Qiu
Summary: This study establishes a model to explain the relationship between flare heating energy and observed soft X-ray emission. By using UV emission as a proxy for heating energy and considering the discrete nature of heating and cooling, the Neupert effect model is modified. The results demonstrate that a two-phase heating model better aligns with observations.
ASTROPHYSICAL JOURNAL
(2021)
Article
Chemistry, Physical
Weifeng Huang, Jianxin Kang, Tingwen Chen, Dawei Pang, Lihua Wang, Hang Wei, Changchun Yang, Dongfeng Zhang, Lin Guo
Summary: Nickel based magnetic nanocrystals have wide applications in magnetic and catalytic fields. Tunable magnetic properties of nickel can be achieved through non-magnetic doping or phase transformation. This study presents a way to control the magnetism of Au@Ni-carbide magnetic materials by adjusting the amount of carbon in the Ni layer, and provides solid evidence for the carbonation process from fcc-Ni to Ni X C instead of phase transformation to hcp-Ni. Further investigation reveals that the magnetism of the hybrids is mainly contributed from the residual fcc-Ni.
Article
Chemistry, Multidisciplinary
Victor Kwan, Shoubhik R. Maiti, Ivan Saika-Voivod, Styliani Consta
Summary: This study investigates the interconversion reaction of NaCl in cold droplets. It is found that the closer the temperature is to the surface, the closer the ion interconversion reaction takes place. In supercooled droplets, there is an enrichment of salt in the subsurface. In the free-ion state, the number density of Cl- has a maximum value in the interior in addition to the well-known maximum in the surface. In terms of reaction dynamics, there is a weak coupling between the interionic NaCl distance reaction coordinate and the solvent degrees of freedom, which is different from the diffusive crossing of the free energy barrier found in bulk solution modeling. The H2O self-diffusion coefficient is at least an order of magnitude larger than that in the bulk solution. Exploiting the enhanced surface ion concentration at low temperature to improve native mass spectrometry ionization methods is proposed.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Xu Zhang, Jingteng Zhao, Gi-Hyeok Lee, Yuan Liang, Boya Wang, Shiqi Liu, Errui Wang, Wanli Yang, Haijun Yu
Summary: This study successfully improves the capacity retention and suppresses voltage decay of Li-rich layered oxides by regulating the surface of the material. The enhanced performance is attributed to the thin, uniform, robust, and compact cathode-electrolyte interphase (CEI) which suppresses surface degradation and stabilizes bulk oxygen reactions.
ADVANCED ENERGY MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Gi-Hyeok Lee, Jungwoo Lim, Jeongyim Shin, Laurence J. J. Hardwick, Wanli Yang
Summary: Cation-disordered rock-salt cathodes (DRX) show potential for high capacity and power density, but face challenges in material deterioration and scalability. Fluorination has been explored to improve performance, but further development is needed to address these issues and enable practical applications.
FRONTIERS IN CHEMISTRY
(2023)
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
Chemistry, Multidisciplinary
Lothar Weinhardt, Dirk Hauschild, Oliver Fuchs, Ralph Steininger, Nan Jiang, Monika Blum, Jonathan D. Denlinger, Wanli Yang, Eberhard Umbach, Clemens Heske
Summary: The sulfur L2,3 X-ray emission spectra of alkaline earth metal sulfides have been investigated. The results show distinct spectral shapes for different compounds, and the spectral calculations based on density functional theory provide an accurate description of the spectral shapes in the upper valence band region. Semi-Auger decays involving configuration interaction produce strong satellites on the low energy side of sulfur 3s-*2p transition, which become more intense as the bonding character becomes more ionic. These satellites can be used as a specific spectral fingerprint for speciation analysis.
Article
Chemistry, Multidisciplinary
Ji Qian, Yang Ha, Krishna Prasad Koirala, Di Huang, Zhi Huang, Vincent S. S. Battaglia, Chongmin Wang, Wanli Yang, Wei Tong
Summary: This study reports the synthesis of a highly fluorinated Li-excess cation-disordered rock salts (DRX) cathode, Li1.2Mn0.6Ti0.2O1.8F0.2, based on cost-effective and earth-abundant transition metals via a solid-state reaction. The fluorinated DRX cathode using an ammonium fluoride precursor exhibits uniform particle size, delivering a specific discharge capacity of 233 mAh g(-1) and specific energy of 754 Wh kg(-1), with 206 mAh g(-1) retained after 200 cycles. The study demonstrates the potential to develop next-generation cost-effective DRX cathodes with enhanced capacity retention for high-energy Li-ion batteries.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Clemens Heske, James C. Carter, Dirk Hauschild, Lothar Weinhardt, Kimberly Horsley, Dimitrios Hariskos, Nicolas Gaillard
Summary: This article presents the electronic surface level positions of different chalcopyrite [Cu(In,Ga)(S,Se)2] thin-film absorbers and discusses their suitability for photoelectrochemical (PEC) water splitting. Suitable band edge energies (CBM and VBM) at the electrode surfaces are necessary for efficient PEC water splitting to enable hydrogen and oxygen evolution. Strategies to optimize chalcopyrite PEC devices for solar water splitting with respect to redox potentials are derived through studying various chalcopyrite variants in growth process, composition, stoichiometry, and surface treatment.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
Tristan Heider, Gustav Bihlmayer, Jakub Schusser, Friedrich Reinert, Jan Minar, Stefan Bluegel, Claus M. Schneider, Lukasz Plucinski
Summary: We demonstrate a new type of geometry-induced spin filtering effect in photoemission in the important quantum material WTe2. The effect arises from its low symmetry, which also gives rise to its exotic transport properties. Through laser-driven spin-polarized angle-resolved photoemission Fermi surface mapping, we observe highly asymmetric spin textures of electrons emitted from the surface states of WTe2. The effect is a manifestation of time-reversal symmetry breaking in the photoemission process and can only be influenced by special experimental geometries.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Abdul-Vakhab Tcakaev, Bastian Rubrecht, Jorge. Facio, Volodymyr. B. Zabolotnyy, Laura. T. Corredor, Laura. C. Folkers, Ekaterina Kochetkova, Thiago R. F. Peixoto, Philipp Kagerer, Simon Heinze, Hendrik Bentmann, Robert. J. Green, Pierluigi Gargiani, Manuel Valvidares, Eugen Weschke, Maurits. W. Haverkort, Friedrich Reinert, Jeroen van den Brink, Bernd Buechner, Anja U. B. Wolter, Anna Isaeva, Vladimir Hinkov
Summary: The recent discovery of the quantum anomalous Hall effect (QAHE) in MnBi2Te4 and MnBi4Te7 indicates the potential of the (MnBi2Te4)(Bi2Te3)(n) family for further improvements in QAHE. The ferromagnetic (FM) ordered MnBi2Te4 septuple layers (SLs) in this family contribute to its promising nature. However, achieving QAHE in MnBi2Te4 and MnBi4Te7 is complicated due to the substantial antiferromagnetic (AFM) coupling between the SLs. By interlacing the SLs with an increasing number of Bi2Te3 quintuple layers (QLs), an FM state advantageous for QAHE can be stabilized. The mechanisms driving the FM state and the number of necessary QLs are not yet understood, and the surface magnetism remains unclear. This study demonstrates robust FM properties in MnBi6Te10 (n = 2) and establishes that its origin lies in the Mn/Bi intermixing phenomenon, thus consolidating its potential for QAHE at elevated temperatures.
Article
Energy & Fuels
Dirk Hauschild, Mary Blankenship, Amandee Hua, Ralph Steininger, Patrick Eraerds, Thomas Niesen, Thomas Dalibor, Wanli Yang, Clemens Heske, Lothar Weinhardt
Summary: The chemical and electronic structure of the interface between a sputter-deposited Zn(O,S) buffer layer and an industrial Cu(In,Ga)(S,Se)(2) (CIGSSe) absorber for thin-film solar cells was investigated using various spectroscopic techniques. It was found that the CIGSSe absorber surface band gap significantly increased compared to bulk-sensitive methods. The measurements also showed the presence of S-Zn and S-O bonds in the Zn(O,S) layer, and an enhanced carrier separation at the interface.
Article
Nanoscience & Nanotechnology
Elizaveta Pyatenko, Dirk Hauschild, Vladyslav Mikhnych, Raju Edla, Ralph Steininger, Dimitrios Hariskos, Wolfram Witte, Michael Powalla, Clemens Heske, Lothar Weinhardt
Summary: In this study, the chemical structure of the Cu(In,Ga)Se-2 (CIGSe) thin-film solar cell absorber surfaces and their interface with a Ga2O3 buffer layer were investigated. The effects of different treatments on the chemical composition and impurities at the absorber surface were analyzed using various spectroscopic techniques. The results suggest that a specific rinsing step can effectively remove impurities and alter the chemical composition of the absorber layer.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Multidisciplinary Sciences
A. de la Torre, B. Zager, F. Bahrami, M. H. Upton, J. Kim, G. Fabbris, G. -H Lee, W. Yang, D. Haskel, F. Tafti, K. W. Plumb
Summary: The authors characterize the material candidate H3LiIr2O6 and find a broad continuum of collective excitations absent of a momentum dependence, suggesting a disordered topological spin liquid. Understanding the interaction between inherent disorder and the fluctuating-spin ground state is crucial for the search of quantum spin liquids.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Raphael C. Vidal, Giovanni Marini, Lukas Lunczer, Simon Moser, Lena Fuerst, Julia Issing, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, Charles Gould, Hartmut Buhmann, Wouter Beugeling, Giorgio Sangiovanni, Domenico Di Sante, Gianni Profeta, Laurens W. Molenkamp, Hendrik Bentmann, Friedrich Reinert
Summary: This study presents a joint experimental and theoretical investigation of the electronic structure in strained HgTe(001) films in the 3D topological-insulator regime, using angle-resolved photoelectron spectroscopy and density functional theory. The results demonstrate detailed agreement with theoretical predictions, including electronic band dispersions and orbital symmetries, surface and bulk contributions, and the importance of Hg 5d states in valence-band formation. The experiments directly image the paradigmatic band inversion in HgTe, revealing its nontrivial band topology.
Article
Chemistry, Physical
Marianne van der Merwe, Raul Garcia-Diez, Leopold Lahn, R. Enggar Wibowo, Johannes Frisch, Mihaela Gorgoi, Wanli Yang, Shigenori Ueda, Regan G. Wilks, Olga Kasian, Marcus Baer
Summary: This study investigates the correlation between the catalytic performance of mixed Ir-TiOx catalysts and the electronic structure of the surface layers. It is found that the degree of titanium oxidation strongly depends on the titanium content, with lower content leading to less oxidation. The addition of titanium stabilizes the catalyst while maintaining high OER activity.
Article
Chemistry, Physical
Wei Yin, Judith Alvarado, Elyse A. Kedzie, Bryan D. McCloskey, Chaochao Dun, Jeffrey J. Urban, Zengqing Zhuo, Wanli Yang, Marca M. Doeff
Summary: An in-depth study of Li4Mn2O5 reveals that the anomalously high charge and discharge capacity in lithium cells is caused by the electrochemical decomposition of Li2O and the reduction of Mn. There is no evidence of reversible oxygen redox contributing to the capacities. The over-reduction is worsened by high charging limits, resulting in rapid capacity fading. Adding spinel LiMn2O4 improves the cycling behavior but decreases the discharge capacity.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
