Article
Chemistry, Physical
Oscar Cabeza, Luisa Segade, Montserrat Dominguez-Perez, Esther Rilo, David Ausin, Julio A. Seijas, M. Pilar Vazquez-Tato, Vladimir Matleev, Alexandr Ievlev, Josefa Salgado, Luis M. Varela
Summary: This paper presents a study on a new family of ionic liquids, investigating the differences in electrical conductivity, viscosity, and diffusion coefficient among various metal thiocyanate ILs. Despite their chemical similarities, these compounds exhibit significant variations in transport properties.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Physical
Jane Banner, Emily Ghosh, Srikanth Gopalan
Summary: The role of porosity in equilibration kinetics in electrical conductivity relaxation (ECR) experiments is highlighted in this study. The use of porous conductivity bars allows for quicker experiments and is critical for determining oxygen exchange kinetics. Both porous and dense bars show similar trends with oxygen partial pressure and differences between oxidation and reduction transients.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Environmental Sciences
Marita Piglowska, Beata Kurc, Lukasz Rymaniak
Summary: The main purpose of these studies is to compare the diffusion coefficient and ionic conductivity of carbon-based anode materials at different temperatures, and propose an interesting method for determining the thermodynamic and kinetic parameters of lithium ion diffusion.
WASTE AND BIOMASS VALORIZATION
(2023)
Article
Chemistry, Physical
Hamideh Basouli, Farkhondeh Mozaffari, Hossein Eslami
Summary: Molecular dynamics simulations were used to study the properties of 1-ethyl-3-methylimidazolium methylsulfate ionic liquid at different temperatures and atmospheric pressures, finding that considering the joint movement of counterions can improve the accuracy of the calculated ionic conductivity compared to experimental data. The study also revealed the quick dissociation of hydrogen bonds and the importance of translational motion in fracture ion-pairing.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Materials Science, Multidisciplinary
Linhao Li, Teresa Roncal-Herrero, John Harrington, Steven J. Milne, Andy P. Brown, Julian S. Dean, Derek C. Sinclair
Summary: The study investigated the influence of adding a small amount of Bi2O3 on grain boundaries in high temperature dielectric solid solution series, leading to significant changes in conductivity and ion switch behavior. At low temperatures, grain boundaries act as electrically blocking layers, while they become highly conductive at higher temperatures due to a phase transition and melting of δ-Bi2O3.
Article
Chemistry, Physical
Tae-Ung Wi, Chanhee Lee, M. Fahmi Rahman, Wooseok Go, Su Hwan Kim, Dae Yeon Hwang, Sang Kyu Kwak, Youngsik Kim, Hyun-Wook Lee
Summary: Studying the stability of NASICON pellets in different aqueous solutions revealed that increasing the concentration and types of ions in the solutions can suppress detrimental reactions between solid electrolytes and water media, while insufficient dissolved ions can lead to inferior chemical stability of the solid electrolyte.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Physical
K. A. Niradha Sachinthani, Jenny R. Panchuk, Yuhang Wang, Tong Zhu, Edward H. Sargent, Dwight S. Seferos
Summary: Polymeric mixed ionic/electronic conductors (MIECs) with controlled structure and mechanically robust properties were prepared and investigated. Copolymers containing thiophene and selenophene repeat units showed significantly higher Li-ion conductivity and electronic conductivity compared to homopolymer counterparts, indicating potential for designing new MIECs.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Farid Taherkhani, Alessandro Fortunelli
Summary: This study investigates the thermal conductivity behavior of silver-gold and silver-palladium alloys using molecular dynamics simulations. The results show that the thermal conductivity exhibits a non-monotonic trend with doping concentration, with the electronic contribution dominant at room temperature and the phonon contribution becoming dominant at high temperature.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Electrochemistry
Junqiao Lee, Jesse W. Mullen, Ghulam Hussain, Debbie S. Silvester
Summary: Microelectrodes are popular in electroanalysis for high current density, which can be further increased by multiplying the number of electrodes in an array configuration. The spacing between microelectrodes significantly affects the deposition effects and current responses, with smaller spacing potentially allowing for higher electrode density.
ELECTROCHIMICA ACTA
(2021)
Article
Engineering, Electrical & Electronic
S. Behera, B. N. Parida, R. K. Parida, R. Padhee
Summary: The eco-friendly polycrystalline sample Mg2LaVO6 was synthesized using the solid state reaction technique. By optimizing the calcination temperature, a single phase new compound was obtained. The sample shows potential applications in multilayer capacitors and micro-electronics, as well as useful thermistor devices.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Physics, Applied
Rakesh Ram, Sanjib Bhattacharya
Summary: In this study, the electrical transport behavior of newly developed Na2O-ZnO-CdO glassy electrolytes at ambient temperature was investigated. The AC conductivity and relaxation behavior were analyzed using the Almond-West formalism. Both frequency and temperature were found to affect the electrical conductivity, which exhibited a flat pattern at low frequencies and dispersion at high frequencies. The DC conductivity and hopping frequency were calculated based on the best fitted experimental data. The study also revealed the dynamical behavior of charge carriers in sodium oxide glassy systems through hopping conduction.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Electrochemistry
Alexander Rudy, Alexander Mironenko, Victor Naumov, Alena Novozhilova, Alexander Skundin, Ivan Fedorov
Summary: A structural model of LiPON solid electrolyte was proposed, and the impedance dependence on frequency was calculated to determine the parameters for best approximation of experimental data. Based on these parameters, the ion diffusion coefficient and conductivity of LiPON were calculated.
Article
Chemistry, Physical
T. M. Cassol, A. R. Duarte, C. S. Ribas, P. R. G. Fernandes
Summary: Broadband Dielectric Spectroscopy (BDS) technique was applied to investigate two ionic liquids, MC1 and MC2, analyzing the variations of complex permittivity and complex conductivity with temperature. The results provide insights into the electrical properties of ionic liquids at different temperatures.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Engineering, Environmental
Linbin Hu, Run Liu, Yang Yang, Qian Fu, Liang Zhang, Xun Zhu, Qiang Liao, Jun Li
Summary: Maintaining electroactive biofilms with good metabolic activity is essential for high and stable performance in bioelectrochemical systems (BESs). Proton transport plays a significant role in biofilm metabolic activity through microenvironment pH, making it crucial to investigate proton transfer properties within the biofilms to enhance BES performance. In this study, the proton transport in electroactive biofilms was explored using in situ microelectrode measurements, which innovatively measured the diffusion coefficient in live biofilms under non-destructive conditions. The non-destructive measurement of diffusion coefficients not only brings the results closer to reality, but also enriches the understanding of biochemical processes and physicochemical information. By combining with a mathematical model, it was demonstrated that the accumulation of protons in the biofilm is a key factor in inhibiting electricity generation. The efficient characterization of proton transfer within the biofilm provides realistic guidance for constructing high-performance BESs.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Rasoul Fallahzadeh, Latif Aref, Nabiollah Gholamiarjenaki, Hormoz Gholami
Summary: This research work investigated the ionic conductivity performance of a prospective polymer electrolyte membrane using molecular dynamics simulation. The results showed that with increasing sulfonation levels, the diffusion coefficients of ions increased, leading to enhanced ionic conductivity. The simulated ionic conductivities of the membrane were comparable to other electrolyte membranes, making it suitable for high-temperature applications.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Physical
Christoph Riedl, Matthaus Siebenhofer, Andreas Nenning, Gernot Friedbacher, Maximilian Weiss, Christoph Rameshan, Johannes Bernardi, Andreas Limbeck, Markus Kubicek, Alexander Karl Opitz, Juergen Fleig
Summary: The addition of minor amounts of Pt into LSF thin film electrodes has been found to improve their oxygen exchange performance, with even a 5 nm layer of Pt doped LSF showing a 2.5-fold increase in polarization resistance. In situ impedance measurements were conducted to compare the p(O-2) and temperature dependent impedance properties of pure and Pt doped LSF, leading to the conclusion that Pt4+ introduces additional active sites.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Matthaeus Siebenhofer, Christoph Riedl, Alexander Schmid, Andreas Limbeck, Alexander Karl Opitz, Juergen Fleig, Markus Kubicek
Summary: The oxygen exchange reaction mechanism on pristine surfaces of SOFC cathode materials was investigated using in situ impedance spectroscopy, revealing similar characteristics among materials with moderate ionic conductivity. By controlling defect concentrations through electrode polarization, significantly different activation energies for oxygen incorporation and evolution were determined.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
C. Herzig, J. Frank, A. Nenning, M. Gerstl, A. Bumberger, J. Fleig, A. K. Opitz, A. Limbeck
Summary: The impact of sulfur incorporation into GDC thin films on their in-plane ionic conductivity was investigated, revealing a detrimental effect on grain boundary conductivity. Online-LASIL was employed to quantify the amount of sulfur incorporated into the films, highlighting a potential pathway for sulfur incorporation and ion transport degradation along GDC grain boundaries with oxysulfide formation.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Ceramics
Matthaeus Siebenhofer, Federico Baiutti, Juan de Dios Sirvent, Tobias M. Huber, Alexander Viernstein, Stefan Smetaczek, Christopher Herzig, Maciej Oskar Liedke, Maik Butterling, Andreas Wagner, Eric Hirschmann, Andreas Limbeck, Albert Tarancon, Jurgen Fleig, Markus Kubicek
Summary: The defect chemistry and electronic trapping energies in undoped single crystalline SrTiO3 were investigated using electrochemical impedance spectroscopy and positron annihilation lifetime spectroscopy. The results showed that the chemical capacitance is a valuable tool for establishing a defect model based on electrochemical measurements and analyzing defect concentrations. The chemical capacitance analysis and positron annihilation lifetime spectroscopy are consistent in quantifying the defect concentrations in SrTiO3.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Nanoscience & Nanotechnology
Martin Krammer, Alexander Schmid, Andreas Nenning, Andreas Ewald Bumberger, Matthaeus Siebenhofer, Christopher Herzig, Andreas Limbeck, Christoph Rameshan, Markus Kubicek, Juergen Fleig
Summary: Electrochemical impedance spectroscopy was used to investigate the chemical capacitance of LSC thin-film electrodes under anodic polarization. The study found that the chemical capacitance decreased with increasing anodic overpotentials for both dense electrodes and electrodes with open porosity. However, after annealing in synthetic air or applying high anodic bias voltages, extremely high chemical capacitance peaks were observed. These peaks were attributed to the development of closed pores in the electrodes. Model calculations based on a real-gas equation accurately predicted the experimentally obtained capacitance increase. The analysis of chemical capacitance in solid oxide electrolysis cells can serve as a nondestructive tool to detect and quantify closed porosity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Electrochemistry
Matthaeus Siebenhofer, Ulrich Haselmann, Andreas Nenning, Gernot Friedbacher, Andreas Ewald Bumberger, Stefan Wurster, Werner Artner, Herbert Hutter, Zaoli Zhang, Juergen Fleig, Markus Kubicek
Summary: The surface morphology and chemistry changes of LSC thin films grown on different substrates were studied under SOFC operation conditions for 100 hours. The formation of particles at the LSC surface was monitored using atomic force microscopy. Different particle formation dynamics were observed depending on the thin film structure. Electron microscopy revealed that the particles were rich in Sr and S. Various measurements were performed on degraded LSC thin films, showing the presence of sulfur on the LSC surface and A-site cation enrichment. Impedance spectroscopy demonstrated an increase in polarization resistance and its activation energy for LSC grown on YSZ over the degradation period.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Christoph Riedl, Matthaeus Siebenhofer, Andreas Nenning, George E. Wilson, John Kilner, Christoph Rameshan, Andreas Limbeck, Alexander K. Opitz, Markus Kubicek, Juergen Fleig
Summary: The oxygen exchange kinetics of Pr0.1Ce0.9O2-delta electrodes were modified by decorating with submonolayer amounts of binary oxides. The OER rate and total conductivity were measured using i-PLD and changes in electrochemical properties were observed after each pulse of surface decoration. The surface chemistry of the electrodes was investigated using NAP-XPS and LEIS. The results showed that the OER rate was significantly altered by the surface decorations, but the fundamental OER mechanism was not affected.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Vedran Vonk, Alexander K. Opitz, Sergey Volkov, Thomas F. Keller, Alexander Hutterer, Pirmin Lakner, Florian Bertram, Ju''rgen Fleig, Andreas Stierle
Summary: Three different platinum oxides were observed during electrochemical potential cycles of platinum thin film model electrodes on yttria-stabilized zirconia at 702 K in air. Electron and atomic microscopy showed delamination and the formation of pyramidlike blisters on the platinum electrode. The identified oxides were an ultrathin PtOx at the buried Pt/YSZ interface, polycrystalline beta-PtO2 inside the blisters, and an ultrathin alpha-PtO2 at the Pt/air interface.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Electrochemistry
Joseph Ring, Lisa Laa, Andreas Limbeck, Vedran Vonk, Sergey Volkov, Andreas Nenning, Juergen Fleig
Summary: In this study, the electrochemical and analytical experiments were conducted to investigate the stability of LLTO with Li-ion-blocking Pt electrodes. It was found that at voltages above 2.5 V, the electrolyte degradation occurred due to the movement of a darkened color front from cathode to anode. The cathode region showed the presence of Ti3+ polarons with high mobility, leading to mixed ion-electron conductivity, while the anode region exhibited a spatially confined, weakly conductive Li depletion zone.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Electrochemistry
Joseph Ring, Andreas Nenning, Juergen Fleig
Summary: LLTO is a promising material in Li ion battery application due to its stable ambient and high ionic conductivity. Under high Li chemical potential, LLTO undergoes a transition from an electrolyte to a high rate capable electrode material. However, the exact voltage of this transition and the electronic conductivity of reduced LLTO were unknown. In this study, we investigated the thermodynamics of lithium insertion and the ion and electron conductivity of reduced LLTO, and proposed a defect chemical model that fits well with the experimental data.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Mattha''us Siebenhofer, Christoph Riedl, Andreas Nenning, Sergej Raznjevic, Felix Fellner, Werner Artner, Zaoli Zhang, Christoph Rameshan, Ju''rgen Fleig, Markus Kubicek
Summary: The oxygen exchange kinetics and surface chemistry of dense LSC thin films on different orientations were investigated using in-situ impedance spectroscopy and NAP-XPS. The results showed that the exchange kinetics on pristine LSC surfaces were fast and independent of orientation. However, in the presence of acidic, gaseous impurities, the (001) orientation was more susceptible to the formation of sulfate adsorbates and performance degradation. This finding has implications for solid oxide cell electrodes with porous materials.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Matthaeus Siebenhofer, Andreas Nenning, George E. Wilson, John A. Kilner, Christoph Rameshan, Markus Kubicek, Juergen Fleig, Peter Blaha
Summary: This study investigates the effects of sulphur adsorbates and other SOFC poisons on the electronic and ionic properties of an SrO-terminated LSC surface and its oxygen exchange kinetics. Experimental and computational methods were used to analyze the surface modifications caused by the adsorbates. The results show that sulphur adsorbates strongly deactivate the LSC surface and affect oxygen vacancy formation energies. The study also reveals a correlation between work function changes and redistributed charge with the acidity of the adsorbed oxide.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Materials Science, Multidisciplinary
Stefan Smetaczek, Andreas Limbeck, Veronika Zeller, Joseph Ring, Steffen Ganschow, Daniel Rettenwander, Juergen Fleig
Summary: LLZO garnets are potential solid electrolytes for solid-state Li batteries, but suffer from chemical interaction with air and humidity. This study investigates the kinetics of Li+/H+ exchange and its dependence on microstructural features, revealing the importance of microstructure in determining the exchange kinetics of LLZO.
MATERIALS ADVANCES
(2022)
Article
Chemistry, Physical
Christoph Riedl, Matthaeus Siebenhofer, Andreas Nenning, Alexander Schmid, Maximilian Weiss, Christoph Rameshan, Andreas Limbeck, Markus Kubicek, Alexander Karl Opitz, Juergen Fleig
Summary: In this study, mixed conducting cathode materials were characterized for their catalytic performance using in situ impedance spectroscopy. The results showed excellent catalytic properties, with polarization resistances two orders of magnitude lower than previously reported. However, traditional measurement setups often led to contamination by sulfate adsorbates, resulting in increased surface polarization resistances. This study highlights the importance of accurately assessing the catalytic properties of these materials.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Multidisciplinary
Alexander Viernstein, Markus Kubicek, Maximilian Morgenbesser, Tobias M. Huber, Matthaeus Siebenhofer, Juergen Fleig
Summary: UV irradiation significantly affects the conductivity of undoped SrTiO3 single crystals, with opposite effects observed in oxidizing and reducing atmospheres. In N2/O2 atmospheres, UV exposure enhances the conductivity, while in H2 atmosphere, it surprisingly decreases the conductivity. The changes in defect concentrations due to UV-driven oxygen incorporation from the gas phase into the oxide are identified as the main cause of these conductivity changes.
MATERIALS ADVANCES
(2022)