Article
Chemistry, Physical
Prosper Ngabonziza, Rotraut Merkle, Yi Wang, Peter A. Aken, Tor S. Bjorheim, Joachim Maier, Jochen Mannhart
Summary: Ionically conducting oxide heterostructures are ideal for studying interfacial effects in solid state ionics, and 2D doping has not been applied in ion conductors before. In this study, epitaxial BaZrO3-BaYOx heterostructures and 2D doping of BaZrO3 by yttrium were reported, with effects on proton conductivity studied. This research not only provides fundamental insight into 2D doping of ion conductors, but also has the potential to improve protonic devices.
ADVANCED ENERGY MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Evgeniy Makagon, Olga Kraynis, Rotraut Merkle, Joachim Maier, Igor Lubomirsky
Summary: The study finds that doping decreases Young's modulus, and nominally dry samples generally have higher Young's modulus. All samples exhibit large non-classical electrostriction effects.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Piotr Winiarz, Kacper Dzierzgowski, Aleksandra Mielewczyk-Gryn, Maria Gazda, Sebastian Wachowski
Summary: Lanthanum orthoantimonate was synthesized using a solid-state synthesis method, with the addition of 1 mol % Ca to enhance protonic conductivity. The materials were found to be single-phase and exhibited non-linear expansion with temperature. Studies showed the material to be a proton conductor under oxidizing conditions, with a conductivity of around 10(-6) S cm(-1) at 800 degrees C, which could be improved through microstructure and doping optimization.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Inorganic & Nuclear
Cyrille Galven, Valerie Albin, Simon Hubert, Virginie Lair, Armelle Ringuede, Marie-Pierre Crosnier-Lopez, Francoise Le Berre
Summary: Two new acentric oxycarbonates Na6Li4MO4(CO3)(4) (M = W and Mo) with promising potential as electrolytes for electrochemical devices were successfully synthesized. The crystal structures of Na6Li4MO4(CO3)(4) (M = W and Mo) were determined to be acentric cubic P-43m space group. The conductivity of both solid and molten phases showed purely ionic behavior and was comparable to classical molten alkali electrolytes.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Wojciech Skubida, Daniel Jaworski, Aleksandra Mielewczyk-Gryn, Sebastian Wachowski, Tadeusz Miruszewski, Kacper Cichy, Konrad Swierczek, Maria Gazda
Summary: This research focuses on the transport properties of high-entropy BaZr1/8Hf1/8Sn1/8Ti1/8Y1/8In1/8Sm1/8Yb1/8O3-x perovskite oxide, with a particular emphasis on proton transport. The presence of proton defects is analyzed using thermogravimetry, and the proton and deuterium conductivities are evaluated using electrochemical impedance spectroscopy. The isotope effect is observed, and the contribution of proton conductivity to the total conductivity is established. Electrical conductivity relaxation studies are performed for the first time on high-entropy oxides, allowing the calculation of water kinetic coefficients and the determination of the chemical diffusion coefficient and chemical surface exchange coefficient of water.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Jagoda Urban-Klaehn, Clarita Y. Regalado Vera, Radoslaw Zaleski, Hanping Ding, Hongmei Luo, Dong Ding
Summary: The study focused on defect chemistry of doped BaZrO3 proton conductors, and its findings have significant implications for proton conductivity. Using positron annihilation lifetime spectroscopy, the researchers showed that yttrium doping increased the trapping rate of positrons, while scandium doping did not have the same effect. Additionally, low-temperature hydration significantly inhibited positron trapping in the samples.
SOLID STATE IONICS
(2023)
Article
Chemistry, Physical
Bettina Schwaighofer, Miguel Angel Gonzalez, Markus Appel, Michael Marek Koza, Ivana Radosavljevic Evans
Summary: In this study, we directly observed the dynamics of oxide ions in Bi0.852V0.148O1.648 and Bi0.852P0.148O1.648 solid electrolytes on nano- and picosecond timescales using quasielastic neutron scattering. By performing comprehensive ab initio molecular dynamics simulations, we successfully reproduced the experimental picosecond data and simulated the scattering function at different temperatures. Our analysis revealed that the picosecond dynamics involve localized motions within the V-O and P-O sublattices, while nanosecond dynamics correspond to oxide ion diffusion through vacancy-hopping in the Bi-O sublattice. The flexibility of the V coordination environment plays a crucial role in the different oxide ion migration pathways and mechanisms, consistent with the superior conductivity of the vanadate.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
A. Shlyakhtina, O. N. Kondrat'eva, G. E. Nikiforova, A. N. Shchegolikhin, D. N. Stolbov, I. Kolbanev, Wenping Liang, N. Lyskov
Summary: The composition, microstructure, electrical and thermal conductivity of Nd2+/-xHf2+/-xO7+/-delta ceramic materials were studied. Composite materials, (Nd2-xHfx)Hf2O7+x/2 (x = 0.2, 0.32, 0.39), containing 4-16 wt% HfO2, exhibited the highest conductivity and the brightest narrow-band luminescence. The (Nd2-xHfx)Hf2O7+x/2 (x = 0.2) composite, with approximately 4 wt% HfO2, had the lowest thermal conductivity.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Chemistry, Physical
Masahiro Shiraiwa, Takafusa Kido, Kotaro Fujii, Masatomo Yashima
Summary: (English Summary:)
This passage discusses the research findings on proton conductors based on (110) layered perovskite structures, achieving high electrical conductivity and proton conductivity through synthesis. Among the materials synthesized, BaNd0.8Ca0.2ScO3.9 exhibited the best performance, showing high proton conductivity at high temperatures.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Physical
Zhaoyu Zhong, Xiaoqian Xu, Zhenhao Zhang, Jiao Li, Xue Guo, Shigang Wu, Haibin Sun
Summary: This study successfully fabricated dense BZCYYb electrolytes at low temperatures using microwave sintering technique, effectively suppressing barium evaporation and promoting grain growth, leading to improved electrical conductivity. The microwave-sintered BZCYYb electrolyte exhibited excellent conductivity at 700 degrees C, indicating its potential application in SOFCs.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Peng Du, Nana Li, Xiao Ling, Zhijun Fan, Artur Braun, Wenge Yang, Qianli Chen, Arthur Yelon
Summary: Proton conductivity in Y-doped BaMO3 follows the Meyer-Neldel rule, indicating that tuning lattice vibration frequency can enhance proton conductivity at low temperatures. The conductivities intersect at an isokinetic temperature, where proton conductivity is independent of activation energy, suggesting the importance of lattice properties in proton conduction mechanism. It is suggested that materials with stiff lattices and high isokinetic temperature can achieve improved proton conductivity at lower temperatures.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Akanksha Yadav, Ram Pyare, Thandavarayan Maiyalagan, Preetam Singh
Summary: Ceramic fuel cells offer more advantages over PMFCs due to their fuel flexibility and high performance at elevated temperature. Simultaneous substitution of K and Ga can improve the low ionic conductivity issues of BaZrO3 based materials at high temperature.
Review
Nanoscience & Nanotechnology
Aroosa Javed, Paulina Palafox Gonzalez, Venkataraman Thangadurai
Summary: In the 21st century, proton exchange membrane fuel cells (PEMFCs) are a promising source of power generation due to their high efficiency and eco-friendly design. However, the critical component of PEMFCs, proton exchange membranes (PEMs), have drawbacks such as high cost and reduction in proton conductivity at high temperatures. Recent research has focused on modifying PEMs through composite materials to improve their stability and proton conductivity. This article discusses the current developments in membranes for PEMFCs, with emphasis on hybrid membranes based on Nafion, PBI, and other nonfluorinated proton conducting membranes.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Andrew J. E. Rowberg, Meng Li, Tadashi Ogitsu, Joel B. Varley
Summary: In this study, first-principles calculations based on density functional theory were used to investigate the properties of hole and electron polarons in barium zirconate (BZO) and barium cerate (BCO). It was found that hole polarons form in both materials, more favorably in BCO. Electron polarons, on the other hand, are stable only in BCO and Ce-containing alloys. Doping BZO and BCO can lead to negligible electron concentrations and larger concentrations of holes and hole polarons.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Coatings & Films
Naveen Manhar Chavan, Prita Pant, G. Sundararajan, P. Suresh Babu
Summary: It is well known that post treatments are necessary for cold sprayed coatings to achieve properties similar to their bulk counterparts, even with high pressure cold spray. In this study, high energy infrared emitters were used as a heating tool for post treating cold sprayed copper based coatings. The influence of heating power density and exposure duration on coating properties and microstructure was comprehensively explored. Pure copper coatings responded well to the mobile post treatment, showing improved microstructure and properties comparable to or better than furnace heat treatment. However, Cu-Al alloy coatings showed less favorable response to both infrared and furnace post treatments, which is discussed based on microstructural observations.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Engineering, Chemical
Roozbeh Mollaabbasi, Lene Jensberg Hansen, Tor Grande, Seyed Mohammad Taghavi, Houshang Alamdari
Summary: This study investigates the effects of fine particle concentration and temperature on the viscoelastic properties of the binder matrix in the formation of carbon anodes. It was found that increasing the fine particle concentration increases viscosity, while increasing temperature reduces viscosity. The three-element Maxwell model accurately predicts the elastic and viscous moduli of the binder matrix.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Chemistry, Physical
Vijayan Sobhana Dilimon, Ragnar Strandbakke, Truls Norby
Summary: This study investigated the impedance spectroscopy of Au electrodes on GDC-LNC composite electrolytes in O2 and O2+CO2 atmospheres. The results suggest that CO2 adsorption in O2+CO2 atmospheres hinders oxygen adsorption and slows down oxygen reduction kinetics. Incorporating LNC melt into GDC reduces polarisation resistance in O2 atmospheres, but increases it in O2+CO2 atmospheres due to the blocking adsorption of CO2.
JOURNAL OF POWER SOURCES
(2022)
Article
Materials Science, Multidisciplinary
Asem Hussein, Zhaohui Wang, Arne Petter Ratvik, Tor Grande, Houshang Alamdari
Summary: This study investigated the impact of bio-pitch on the electrochemical behavior of carbon anodes. The results showed that using bio-pitch as a binder slightly improved the electrochemical performance of the anodes.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Reshma K. K. Madathil, Truls Norby
Summary: This study introduces the use of stable and highly conducting ceramic oxide as interconnects in oxide thermoelectric generators, reducing contact resistance and improving performance and durability.
SOLID STATE SCIENCES
(2022)
Article
Materials Science, Multidisciplinary
Mtabazi G. Sahini, Kjell Wiik, Tor Grande
Summary: The study found that Co diffusion was significant in the La2NiO4+delta (LN) and CoO diffusion couples, while Ni diffusion was minor, leading to the formation of LaCoO3 and other compounds in the LN layer.
Article
Materials Science, Multidisciplinary
Inger-Emma Nylund, Maria Tsoutsouva, Tor Grande, Dennis Meier
Summary: In this study, we investigated the ferroelectricity of gadolinium molybdate using temperature-dependent X-ray diffraction. The results showed that the spontaneous polarization of gadolinium molybdate is induced by a structural instability in the ferroelectric phase, and the displacement of different cations follows different critical behavior.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Xiaolan Kang, Vilde Mari Reinertsen, Kevin Gregor Both, Augustinas Galeckas, Thomas Aarholt, Oystein Prytz, Truls Norby, Dragos Neagu, Athanasios Chatzitakis
Summary: There is a growing demand to control and enhance the stability and efficacy of nanoparticles (NPs) for photo- and electrochemical energy conversion applications. The galvanic replacement/deposition method offers a simpler and safer approach to produce a wide range of hybrid nanostructures with increased tailorability. These bimetallic nanostructures, supported on SrTiO3, show exceptional activity in plasmon-assisted photoelectrochemical water oxidation reactions.
Article
Chemistry, Multidisciplinary
Frode Hadegreesskjold Fagerli, Zhaohui Wang, Tor Grande, Henning Kaland, Sverre M. Selbach, Nils Peter Wagner, Kjell Wiik
Summary: This study demonstrates the use of hydrolyzation with a continuous gas flow to control the termination groups of multilayered MXene particles, resulting in nearly F-free and partly bare MXene materials. The hydrolyzation temperature was found to be crucial for controlling the properties and stability of the MXene materials. The results provide new insights into the thermal stability of MXene in hydrated atmospheres.
Article
Chemistry, Multidisciplinary
Viviann Hole Pedersen, Anders Bank Blichfeld, Kristine Bakken, Dmitry Chernyshov, Tor Grande, Mari-Ann Einarsrud
Summary: Aqueous chemical solution deposition (CSD) is a method for preparing oxide thin films, and this study investigates the formation mechanism of different crystal orientations using in situ synchrotron X-ray diffraction. The results highlight the importance of controlling nucleation and growth for film orientation and structure.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Chemistry, Inorganic & Nuclear
Inger-Emma Nylund, Nora Statle Londal, Julian Walker, Per Erik Vullum, Mari-Ann Einarsrud, Tor Grande
Summary: The crystal structure of tetragonal tungsten bronzes with different cations occupying the A1 and A2 lattice sites has been systematically studied in this research. The occupancy of alkali cations on the A1 and A2 sites was determined by combining X-ray diffraction and scanning transmission electron microscopy with energy-dispersive spectroscopy. The results revealed that the cation occupancy on the A1 and A2 sites is influenced by the size variation of the alkali cations.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Trygve M. Raeder, Shuyu Qin, Rama K. Vasudevan, Tor Grande, Joshua C. Agar, Michael J. Zachman
Summary: Ferroelectrics are increasingly used in electronic devices for extreme environments. This study investigates the collective switching behavior of ferroelectric domain structures and discovers high-speed switching with ordered domain walls. The findings have implications for high-speed tunable dielectrics and low-voltage ferroelectric memories and logic.
Article
Chemistry, Physical
Inger-Emma Nylund, Caren Regine Zeiger, Ding Peng, Per Erik Vullum, Julian Walker, Mari-Ann Einarsrud, Tor Grande
Summary: A first-principles study of the tetragonal tungsten bronze (TTB) K4Bi2Nb10O30 has found in-plane polarization in contrast to the out-of-plane polarization found in most TTBs due to the effect of Bi 6s lone pair. By replacing the lead-containing material PN with KBN, a lead-free analog to morphotropic phase boundaries can potentially be achieved. The synthesis and properties of A4Bi2Nb10O30 (ABN, A = Na, K, Rb) were investigated to determine the structure and electrical properties, with particular focus on the role of the Bi 6s lone pair.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Lulu Jiang, Truls Norby, Donglin Han
Summary: We investigated the proton conducting properties of doped SrZrO3 and found that it exhibits higher transport numbers and other advantages as an electrolyte in proton ceramic electrochemical cells. Through analysis of the chemical expansion properties of SrZr0.9Y0.1O3-δ (SZY10), we determined the partial conductivities of ions and electron holes, as well as the high ionic transport numbers in oxidizing atmospheres and the high electron transport numbers in reducing atmospheres. These results are explained based on defect chemistry and a brick layer model.
Article
Electrochemistry
Elise R. R. Ostli, Alma Mathew, Julian R. R. Tolchard, Daniel Brandell, Ann Mari Svensson, Sverre M. M. Selbach, Nils P. P. Wagner
Summary: The ionic liquid-based electrolyte comprising 1.2 M lithium bis(fluorosulfonyl)imide in N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide has been evaluated as a suitable system for the high-voltage cathode material LiNi0.5-xMn1.5+xO4 when cycled vs. graphite anodes. The IL electrolyte showed improved oxidative stability compared to the state-of-the-art LiPF6 electrolyte. The LNMO||graphite full cells with the IL electrolyte exhibited enhanced cycling performance, especially at elevated temperatures.
BATTERIES & SUPERCAPS
(2023)
Article
Chemistry, Physical
Frode Haskjold Fagerli, Per Erik Vullum, Tor Grande, Zhaohui Wang, Sverre M. Selbach, Kjell Wiik, Nils Peter Wagner
Summary: Gas hydrolysation is demonstrated as a selective and efficient method to substitute F terminations with O-related terminations in multilayered MXene particles. The pre-intercalation of cations and the hydrolysation process enable structural pillaring and achieve significant F reduction without significant oxidation. This approach has potential for controlling the electrochemical performance of MXene particles.
