On the Role of the Porous Transport Layer Structure in Polymer Electrolyte Water Electrolysis

Non-optimal oxygen transport in polymer electrolyte water electrolysis is expected to cause severe efficiency losses at high current density. In this study, we shed the first light on the complex fluid transport in PTL materials using operando X-ray tomographic microscopy.

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Polymer Electrolyte Water Electrolysis: Correlating Porous Transport Layer Structural Properties and Performance: Part I. Tomographic Analysis of Morphology and Topology

Journal of The Electrochemical Society ◽

10.1149/2.0561904jes ◽

2019 ◽

Vol 166 (4) ◽

pp. F270-F281 ◽

Cited By ~ 22

Author(s):

Tobias Schuler ◽

Ruben De Bruycker ◽

Thomas J. Schmidt ◽

Felix N. Büchi

Keyword(s):

Polymer Electrolyte ◽

Structural Properties ◽

Water Electrolysis ◽

Transport Layer ◽

And Topology ◽

And Performance ◽

Tomographic Analysis

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Effect of High Salt Concentration on Ion Clustering and Transport in Polymer Solid Electrolytes: a Molecular Dynamics Study of PEO-LiTFSI

10.26434/chemrxiv.6294941.v1 ◽

2018 ◽

Author(s):

Nicola Molinari ◽

Jonathan P. Mailoa ◽

Boris Kozinsky

Keyword(s):

Polymer Electrolyte ◽

Salt Concentration ◽

Rational Design ◽

Material System ◽

Ion Dynamics ◽

High Concentration ◽

Anion Clusters ◽

Poly Ethylene Oxide ◽

Poly Ethylene

<div> <div> <div> <p>The model and analysis methods developed in this work are generally applicable to any polymer electrolyte/cation-anion combination, but we focus on the currently most prominent polymer electrolyte material system: poly(ethylene) oxide/Li- bis(trifluoromethane) sulfonamide (PEO + LiTFSI). The obtained results are surprising and challenge the conventional understanding of ionic transport in polymer electrolytes: the investigation of a technologically relevant salt concentration range (1 - 4 M) revealed the central role of the anion in coordinating and hindering Li ion movement. Our results provide insights into correlated ion dynamics, at the same time enabling rational design of better PEO-based electrolytes. In particular, we report the following novel observations. 1. Strong binding of the Li cation with the polymer competes with significant correlation of the cation with the salt anion. 2. The appearance of cation-anion clusters, especially at high concentration. 3. The asymmetry in the composition (and therefore charge) of such clusters; specifically, we find the tendency for clusters to have a higher number of anions than cations.</p> </div> </div> </div>

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Effect of High Salt Concentration on Ion Clustering and Transport in Polymer Solid Electrolytes: a Molecular Dynamics Study of PEO-LiTFSI

10.26434/chemrxiv.6294941 ◽

2018 ◽

Author(s):

Nicola Molinari ◽

Jonathan P. Mailoa ◽

Boris Kozinsky

Keyword(s):

Polymer Electrolyte ◽

Salt Concentration ◽

Rational Design ◽

Material System ◽

Ion Dynamics ◽

High Concentration ◽

Anion Clusters ◽

Poly Ethylene Oxide ◽

Poly Ethylene

<div> <div> <div> <p>The model and analysis methods developed in this work are generally applicable to any polymer electrolyte/cation-anion combination, but we focus on the currently most prominent polymer electrolyte material system: poly(ethylene) oxide/Li- bis(trifluoromethane) sulfonamide (PEO + LiTFSI). The obtained results are surprising and challenge the conventional understanding of ionic transport in polymer electrolytes: the investigation of a technologically relevant salt concentration range (1 - 4 M) revealed the central role of the anion in coordinating and hindering Li ion movement. Our results provide insights into correlated ion dynamics, at the same time enabling rational design of better PEO-based electrolytes. In particular, we report the following novel observations. 1. Strong binding of the Li cation with the polymer competes with significant correlation of the cation with the salt anion. 2. The appearance of cation-anion clusters, especially at high concentration. 3. The asymmetry in the composition (and therefore charge) of such clusters; specifically, we find the tendency for clusters to have a higher number of anions than cations.</p> </div> </div> </div>

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Effect of Anisotropic Gas Diffusion Layer Structure on the Cathode Dead-End Mode of Polymer Electrolyte Membrane Fuel Cells for the Submarine

Journal of the KNST ◽

10.31818/jknst.2019.09.2.2.66 ◽

2019 ◽

Vol 2 (2) ◽

pp. 66-70

Author(s):

Jeong Hoon Seo ◽

Dong Kyu Kim ◽

Hyun Min Baek

Keyword(s):

Fuel Cells ◽

Polymer Electrolyte ◽

Diffusion Layer ◽

Layer Structure ◽

Polymer Electrolyte Membrane ◽

Gas Diffusion Layer ◽

Gas Diffusion ◽

Electrolyte Membrane ◽

Dead End

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Applications of two dimensional material-MXene for proton exchange membrane fuel cells (PEMFCs) and water electrolysis

Current Nanoscience ◽

10.2174/1573413716999200614140513 ◽

2020 ◽

Vol 16 ◽

Author(s):

Chanchan Fan ◽

Peng Zhang ◽

Ranran Wang ◽

Yezhu Xu ◽

Xingrui Sun ◽

...

Keyword(s):

Fuel Cells ◽

Water Splitting ◽

Proton Exchange Membrane ◽

Layer Structure ◽

Metal Layer ◽

Water Electrolysis ◽

Proton Exchange ◽

Two Dimensional ◽

Max Phases ◽

Early Transition Metal

: A new kind of two-dimensional (2D) materials MXene (early transition metal carbides, nitrides and carbonitrides) is obtained by selective etching the A element from the MAX phases. MXene exhibits both the metallic conductivity and the hydrophilic nature due to its metal layer structure and hydroxyl or oxygen terminated surfaces. This review provides an overview of the MXene used in the electrolytes and electrodes for the fuel cells and water splitting. MXene with functional groups termination could construct ion channels that significantly benefits to the ion conductivity through the electrolyte. The metal supported by MXene interaction offers electronic, compositional, and geometric effects that could enhance the catalytic activity and stability. MXene have already shown promising performance for fuel cells and water electrolysis. Herein, the etching and intercalation methods of MXene in recent years are summarized. The applications of MXene for fuel cells electrolyte, catalyst and water splitting catalyst are revealed to provide more brief idea for MXene used as new energy materials.

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Functional Specificity of the Members of the Sos Family of Ras-GEF Activators: Novel Role of Sos2 in Control of Epidermal Stem Cell Homeostasis

Cancers ◽

10.3390/cancers13092152 ◽

2021 ◽

Vol 13 (9) ◽

pp. 2152

Author(s):

Fernando C. Baltanás ◽

Cynthia Mucientes-Valdivieso ◽

L. Francisco Lorenzo-Martín ◽

Natalia Fernández-Parejo ◽

Rósula García-Navas ◽

...

Keyword(s):

Stem Cell ◽

Layer Structure ◽

3D Culture ◽

Hair Follicles ◽

Specific Cell ◽

Epidermal Stem Cell ◽

Primary Keratinocytes ◽

Cell Homeostasis ◽

Primary Mouse

Prior reports showed the critical requirement of Sos1 for epithelial carcinogenesis, but the specific functionalities of the homologous Sos1 and Sos2 GEFs in skin homeostasis and tumorigenesis remain unclear. Here, we characterize specific mechanistic roles played by Sos1 or Sos2 in primary mouse keratinocytes (a prevalent skin cell lineage) under different experimental conditions. Functional analyses of actively growing primary keratinocytes of relevant genotypes—WT, Sos1-KO, Sos2-KO, and Sos1/2-DKO—revealed a prevalent role of Sos1 regarding transcriptional regulation and control of RAS activation and mechanistic overlapping of Sos1 and Sos2 regarding cell proliferation and survival, with dominant contribution of Sos1 to the RAS-ERK axis and Sos2 to the RAS-PI3K/AKT axis. Sos1/2-DKO keratinocytes could not grow under 3D culture conditions, but single Sos1-KO and Sos2-KO keratinocytes were able to form pseudoepidermis structures that showed disorganized layer structure, reduced proliferation, and increased apoptosis in comparison with WT 3D cultures. Remarkably, analysis of the skin of both newborn and adult Sos2-KO mice uncovered a significant reduction of the population of stem cells located in hair follicles. These data confirm that Sos1 and Sos2 play specific, cell-autonomous functions in primary keratinocytes and reveal a novel, essential role of Sos2 in control of epidermal stem cell homeostasis.

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