Article
Electrochemistry
Niroodha R. Pitawela, Scott K. Shaw
Summary: This study focuses on the capacitance measurements at the gold-IL interface with [Emim][TFO] IL, and reveals the impact of experimental data collection methods on capacitive hysteresis. A systematic approach to collect reproducible capacitance data for IL systems is suggested.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Electrochemistry
Aleksey Khlyupin, Irina Nesterova, Kirill Gerke
Summary: Electrode surface roughness has a significant impact on the molecular scale structure of the electric double layer. We derived analytical solutions for the differential capacitance of the electric double layer near a rough electrode surface and compared them with experimental and numerical studies. Two causes of ion separation, ion size asymmetry and electrode surface roughness, were considered. The model predicts a transformation of the differential capacitance curve from a bell shape to a camel shape due to electrode surface roughness.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Qianlu Zheng, Zachary A. H. Goodwin, Varun Gopalakrishnan, Alexis G. Hoane, Mengwei Han, Ruixian Zhang, Nathaniel Hawthorne, James D. Batteas, Andrew A. Gewirth, Rosa M. Espinosa-Marzal
Summary: This study investigates the influence of water on the performance of electrochemical devices using hydrophilic and hydrophobic ionic liquids as electrolytes. The results show that water uptake slightly reduces the electrochemical stability of ionic liquids and significantly affects the potential of zero charge of graphene. Hydrophilic ionic liquids efficiently screen surface charge, while hydrophobic ones are less efficient. Water uptake also leads to changes in the interfacial layering, which is important for the design of graphene-based electrochemical devices.
Article
Chemistry, Physical
Maximilian Schalenbach, Yasin Emre Durmus, Shay A. Robinson, Hermann Tempel, Hans Kungl, Ruediger-A Eichel
Summary: Gold is used as a model electrode to study the frequency dispersion and capacitance changes of the double layer in perchloric acid. The study reveals that the frequency dispersion of capacitance is mainly influenced by the electric field-driven ion separation, and is almost independent of the excitation amplitude.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Electrochemistry
Junsoo Han, Ho Lun Chan, Marlene G. Wartenberg, Helge H. Heinrich, John R. Scully
Summary: The impedance of metal/oxide/RTIL interfaces can be separated into oxide layer and double layer capacitances using electrochemical impedance spectroscopy, allowing for determination of oxide layer thickness and monitoring of structural metal interfaces in RTILs containing water.
ELECTROCHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Tatau Shimada, Norio Takenaka, Yasunobu Ando, Minoru Otani, Masashi Okubo, Atsuo Yamada
Summary: In this study, the atomic-scale double-layer structure of MXene electrodes with different terminated halogen elements was systematically investigated using density functional theory calculations. The results showed a clear relationship between the atomic number of the terminated halogen atoms and the capacitance.
CHEMISTRY OF MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Yong An, Hongquan Wang, Zhigao Yang, Jingxian Yu, Shengping Wang
Summary: An integrated configuration of organic active material electrode-solid polymer electrolyte has been synthesized via in situ polymerization. The use of a bridge - the naphthalene urethane bond - improves the Li+ transport at the electrode/SPE interface, resulting in enhanced electrochemical and safety performance of the battery.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Review
Chemistry, Physical
Lulu Zhang, Jun Huang
Summary: This Opinion article addresses the challenges in measuring and interpreting the electric double layer (EDL) at Pt(111)/aqueous solution interfaces using classical electrochemical methods. The article discusses discrepancies in measuring double layer capacitance, examines assumptions and limitations of the Frumkin-Melik-Gaikazyan (FMG) model, and compares the capacitance values derived from cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The article aims to contribute to a better understanding of the EDL at Pt(111)/aqueous solution interfaces.
CURRENT OPINION IN ELECTROCHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Duoling Cao, Zuhong Li, Wenbo Li, Ke Pei, Xu Zhang, Li Wan, Li Zhao, Alexey Cherevan, Dominik Eder, Shimin Wang
Summary: Carbon counter electrode-based perovskite solar cells (C-PSCs) are considered promising due to their stability and low cost. This study used two novel pheniramine halides to modify the interface between the electron transport layer and perovskite layer, resulting in improved device performance. The modified C-PSCs achieved higher power conversion efficiency compared to the control device, and the unencapsulated modified device maintained a high level of its initial efficiency under ambient conditions for 800 hours. This study suggests the potential application of multifunctional complex molecules in high-efficiency and stable C-PSCs.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Zachary A. H. Goodwin, Michael McEldrew, J. Pedro de Souza, Martin Z. Z. Bazant, Alexei A. A. Kornyshev
Summary: The understanding of the properties of super-concentrated electrolytes, particularly ionic liquids, in both bulk and interfacial states has been of great interest for their potential applications in supercapacitors and batteries. A recent theoretical development by McEldrew et al. provides insights into reversible ion associations in bulk ionic liquids, which considers the formation of various clusters and an ionic network. In this study, the authors adopt and expand this approach to understand the associations of ionic liquids in the electrical double layer at electrified interfaces.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Austin Yuhang Yap, Sook Wai Phang, Chiam-Wen Liew
Summary: In this study, gel polymer electrolytes (GPEs) based on poly(vinyl acetate) (PVAc) were synthesized using ex-situ polymerization. The GPEs were prepared from precursor solutions containing different volume ratios of vinyl acetate monomer and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIMTFSI) with a fixed concentration of lithium bis(trifluoromethylsulfonyl)imide (LiTFSI). The GPE with 35% (v/v) of BMIMTFSI showed the highest ionic conductivity and a glass transition temperature of -28.01°C. Addition of BMIMTFSI increased the specific capacitance of the GPEs and improved their energy and power densities.
Article
Chemistry, Physical
Oumaima Gharbi, Mai T. T. Tran, Mark E. Orazem, Bernard Tribollet, Mireille Turmine, Vincent Vivier
Summary: This study identifies the different contributions of interfacial capacitance in passive materials or thin protective coatings deposited on electrode surfaces. The method involves a graphical analysis of EIS results to determine both passive-film capacitance in the high-frequency domain and double-layer capacitance in the low-frequency domain. It demonstrates the necessity of correcting high-frequency data for the double-layer contribution and provides a method independent of the physicochemical origins of frequency dispersion in interfacial capacitances.
Article
Nanoscience & Nanotechnology
Leon Katzenmeier, Simon Helmer, Stephan Braxmeier, Edwin Knobbe, Aliaksandr S. Bandarenka
Summary: This study observed the formation of space charge layer in Li-conducting solid electrolytes, analyzed its properties using impedance spectroscopy and physical equivalent circuit, and calculated the effective thickness of the space charge layer to be around 60 nm. The relative permittivity of the electrolytes, specific resistance of the space charge layer, and the effective thickness of the electric double layer (around 0.7 nm) were also estimated.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Electrochemistry
W. D. Judge, J. Paeng, G. Azimi
Summary: This study conducted a detailed electrochemical investigation of pure molten iron in slag using impedance spectroscopy, measuring various fundamental physiochemical properties for the first time and discussing the electric double layer formed between molten iron and slag.
ELECTROCHIMICA ACTA
(2021)
Article
Electrochemistry
Jinju Kim, Jinsik Shin, Hyun Ju Yang, Chung Mu Kang, Donghoon Han, Je Hyun Bae
Summary: This study investigates the influence of ion size and hydrophobicity on the charging dynamics of nanoporous electrodes. As the size of ions decreases and their hydrophobicity increases, the capacitance increases and the movement of ions within the nanopores becomes less restricted. The microporous Pt electrode exhibits better performance than the mesoporous carbon electrode when used with a hydrophilic electrolyte.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Virology
Christoph Jung, Dorota Kmiec, Lennart Koepke, Fabian Zech, Timo Jacob, Konstantin M. J. Sparrer, Frank Kirchhoff
Summary: The recently identified Omicron variant of SARS-CoV-2 is the fifth variant of concern and is characterized by significant changes in the viral Spike protein, possibly leading to increased transmission efficiency and evasion of neutralizing antibodies. Despite quickly outcompeting the Delta variant, Omicron appears to be overall less pathogenic than other variants.
JOURNAL OF VIROLOGY
(2022)
Article
Electrochemistry
Sven J. Zeller, Tanja Geng, Maximilian U. Ceblin, Matthias Uhl, Alexander J. C. Kuehne, Ludwig A. Kibler, Timo Jacob
Summary: The electrochemical behavior of Au(111) in contact with deep eutectic solvents (DESs) was investigated through cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and immersion experiments. The adsorption of chloride, nitrate, and sulfate anions on Au(111) in DESs was found to be similar to that in dilute aqueous solutions.
Article
Chemistry, Physical
Laura Braunwarth, Christoph Jung, Timo Jacob
Summary: This study uses molecular dynamics simulations to investigate the structure and dynamics of electrode-electrolyte interfaces, focusing on the Pt(111)/water interface. The results reveal changes in water molecule orientation and intermolecular ordering, challenging previous assumptions about their correlation to free charge density. This work contributes to our understanding of electric double layers and electrochemical processes.
Editorial Material
Electrochemistry
Tanja Geng, Benjamin W. Schick, Matthias Uhl, Alexander J. C. Kuehne, Ludwig A. Kibler, Maximilian U. Ceblin, Timo Jacob
Article
Chemistry, Multidisciplinary
Matthias Uhl, Tanja Geng, Philipp A. Schuster, Benjamin W. Schick, Matthias Kruck, Alexander Fuoss, Alexander J. C. Kuehne, Timo Jacob
Summary: By replacing the electrolyte with a deep eutectic solvent and using a polymer as the electrode, an all-organic battery can be achieved. The combination of different solvents and salt concentrations affects the stability and viscosity of the battery. The eutectic mixture with a 1:6 ratio offers the best balance between stability and viscosity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Evelyn Artmann, Lukas Forschner, Konstantin M. Schuettler, Mohammad Al-Shakran, Timo Jacob, Albert K. Engstfeld
Summary: Researchers propose a simple method for the preparation of nanoporous gold films, which can be achieved by high voltage electrolysis or anodic contact glow discharge electrolysis. The structural properties of the resulting films can be controlled by adjusting the electrolysis conditions and the reduction reaction conditions.
Article
Chemistry, Multidisciplinary
Florian Fiesinger, Daniel Gaissmaier, Matthias van den Borg, Julian Bessner, Adri C. T. van Duin, Timo Jacob
Summary: One of the key challenges in the development of magnesium-ion batteries (MIB) is the formation of a passivating boundary layer at the magnesium anode. A Mg/O ReaxFF parameter set was developed to accurately model the degradation process of the magnesium anode by O-2 impurities. It was found that O-2 immediately dissociates upon first contact with the magnesium anode, leading to high temperatures and further oxidation. The trained force field can be used to study reactions in Mg-air batteries and the oxidation of magnesium metal in general.
Article
Electrochemistry
Daniel Rutz, Ingolf Bauer, Felix Brauchle, Timo Jacob
Summary: In this study, user-defined reference electrodes based on LFP were fabricated using an ultrashort pulse laser. The results showed that these electrodes have minimal impact on the cell capacity and can provide reproducible voltage output at low to moderate C-rates. They also do not affect the cell expansion during cycling.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Julia Bord, Bjoern Kirchhoff, Matthias Baldofski, Christoph Jung, Timo Jacob
Summary: Density functional theory (DFT) is utilized to investigate the electronic structure of platinum clusters on different graphene substrates. The size and defects of both the clusters and the graphene substrates are examined. The results reveal that larger vacancies lead to stronger binding of Pt clusters, while defect-free graphene shows more exothermic formation energy with increasing cluster size. Oxygen-free graphene supports are crucial for successful attachment of Pt, and cluster stability depends on the number and ratio of Pt-C, Pt-Pt, and Pt-O bonds rather than the cluster geometry.
Article
Chemistry, Physical
Hongyuan Yang, Pramod V. Menezes, Guoliang Dai, Gonela Vijaykumar, Ziliang Chen, Mohammad Al-Shakran, Timo Jacob, Matthias Driess, Prashanth W. Menezes
Summary: Developing bifunctional electrodes for oxidation catalysis is highly desirable for hydrogen and value-added chemicals production. Here, we directly activate the nickel foam through the incorporation of elemental P (P-NF) using a facile, controllable, and ultrafast in-liquid plasma electrolysis approach. The practical bifunctionality of P-NF is additionally verified with selective oxygenation of organics forming value-added chemicals.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Changbin Im, Bjorn Kirchhoff, Igor Krivtsov, Dariusz Mitoraj, Radim Beranek, Timo Jacob
Summary: Computational investigation of PCN materials can lead to better understanding and optimization strategies. Thermochemical calculations predict stable structural motifs and show that condensed PCN domains in a less condensed framework can have desirable optical properties.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Lukas Forschner, Evelyn Artmann, Timo Jacob, Albert K. Engstfeld
Summary: Applying an external potential difference between two electrodes leads to a voltage drop in an ion conducting electrolyte. The electrolyte potential is relevant in electrochemistry and various applications such as bipolar electrochemistry, ohmic microscopy, or contact glow discharge electrolysis. This study focuses on the electrolyte potential during high voltage electrolysis in an electrolysis cell using reversible hydrogen electrodes as reference electrodes. A computational COMSOL model is used to support the experimental findings, and the influence of cell geometry on the electrolyte potentials is evaluated. The amount of oxide formed during high voltage electrolysis is found to be related to the current rather than the applied voltage, based on the knowledge of potential distribution.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Review
Chemistry, Physical
Bjoern Kirchhoff, Christoph Jung, Daniel Gaissmaier, Laura Braunwarth, Donato Fantauzzi, Timo Jacob
Summary: Nanoparticles (NPs) as heterogeneous catalysts have large active surface area and size-dependent catalytic properties. The ability to computationally predict the most favorable NP structures for catalytic reactions is important for material optimization. However, simulations of NP model systems present unique challenges to computational scientists and require different data analysis strategies compared to simulations of single crystal surface models. This work aims to review analytical methods and data analysis strategies for extracting thermodynamic trends from NP simulations.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Andreas Hoffmann, Matthias Uhl, Maximilian Ceblin, Felix Rohrbach, Joachim Bansmann, Marcel Mallah, Holger Heuermann, Timo Jacob, Alexander J. C. Kuehne
Summary: In this study, carbonization of polyacrylonitrile nanofiber nonwovens using an atmospheric pressure plasma jet was explored. The resulting carbon nanofiber nonwovens showed high conductivity and surface roughness, making them suitable for supercapacitor electrode applications with good capacitance performance.
C-JOURNAL OF CARBON RESEARCH
(2022)
Article
Electrochemistry
Hagar K. Hassan, Attila Farkas, Alberto Varzi, Timo Jacob
Summary: One of the main issues with metal organic framework (MOF)-based solid electrolytes (SE) is the high content of guest solvent, which reduces the hardness and stability of SE. This study presents a strategy to minimize guest solvent content and demonstrates the use of mixed metal organic frameworks to enhance ionic conductivity. The mixed MOF-SEs show good stability and reversibility in the presence of Mg electrodes.
BATTERIES & SUPERCAPS
(2022)
