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Perfluorosulfonic acid proton exchange membrane with double proton site side chain for high-performance fuel cells at low humidity

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Journal of materials science & Technology 2023年第35期166卷 155-163页

作者： Hongyun Tan Shengqiu Zhao S.Eltahir Ali Shuhong Zheng Abdullah K.Alanazi Rui Wang Haining Zhang Hala M.Abo-Dief Ben Bin Xu Hassan Algadi Handong Li Priyanka Wasnik Zhanhu Guo Haolin Tang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Science and Technology University College-RanyahTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200China Integrated Composites Laboratory(ICL) Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Electrical Engineering Faculty of EngineeringNajran UniversityNajran11001Saudi Arabia

Structural optimization of ionomers is an effective strategy for achieving high-performance proton ex-change membranes(PEMs)under low relative humidity(RH)*** this study,sulfonimide group and trifluoromethanesulfonate acid(TFSA)ionic liquids were introduced to the perfluorosulfonic acid(PFSA)side chain,resulting in polymer membranes with varying chain lengths(i.e.,PFC_(2)-TF-SI,PFC_(4)-TF-SI,and PFC_(5)-TF-SI).This dual proton-conducting structure extended the length of the hydrophilic side chain and enhanced the hydrophobic-hydrophilic phase separation,aiding in the formation of proton transport ***,the proton conductivity of PFC_(5)-TF-SI and PFC_(2)-TF-SI membranes reached 7.1 and 10.6 mS/cm at 30%RH and 80℃,respectively,which were approximately 29.1%and 92.7%higher than that of the pristine PFC_(5)-SA membrane(5.5 mS/cm).Furthermore,the maximum power density of the PFC_(5)-TF-SI and PFC_(2)-TF-SI membranes from the built single fuel cell achieved 649 and 763 mW/cm^(2) at 30%RH and 80℃,respectively,which were higher than that of the pristine PFC_(5)-SA membrane(567 mW/cm^(2))by about 14.5%and 34.6%,***,this study provides a strategy for PEM design under low RH conditions.

关键词： Proton exchange membrane Structural design Dual proton conduction Hydrophilic channel Proton conductivity Fuel cells

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Experimental and Numerical Evaluation of the Integrity of Cement and Geopolymer Under Low and Elevated Temperature Well Conditions 57

Experimental and Numerical Evaluation of the Integrity of Ce...

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57th US Rock Mechanics/Geomechanics Symposium

作者： Wu, Y. Salehi, S. Kamali, M. Khalifeh, M. Samarakoon, S.M.S.M.K. Mewbourne School of Petroleum and Geological Engineering University of Oklahoma United States Department of Energy and Petroleum Engineering University of Stavanger Stavanger Norway Department of Mechanical and Structural Engineering and Materials Science University of Stavanger Stavanger Norway

ISBN: (纸本)9780979497582

Rock-based geopolymer is an inorganic polymer consisting of granite mine waste and metallurgical industry byproducts. Previous studies have investigated that the rock-based geopolymer has a potential to be an alternative to Portland cement for preventing long-term degradation. In this paper, instead of mechanical well integrity, the performance of mud displacement using the rock-based geopolymer with different retarding additives is evaluated. The investigation includes experimental and simulated studies. In the experiments, rheological properties (i.e., shear stress-shear rate curves and thickening time) are measured. A 3D computational fluid dynamic (CFD) model is developed to simulate the mud displacement in the annulus between the casing and formation. Since previous reports and publications presented that the well inclination was a major challenge in cementing procedures due to gravity effects, this paper focuses on the displacement in horizontal and high-inclined wells. Oil-base drilling fluidwas used as the representative fluid. The effect of different cement additives adding to the geopolymer on the mud displacement, including gluconic acid, sucrose, calcium chelator, and sodium poly-naphthalene as dispersant and retarder are evaluated to provide a recommendation for rock-based geopolymer additives. Wellbore geometries is another investigating parameter. The paper compares the performance of normal, rectangle, and real-shape annulus. The real-shape well geometry was developed based on the caliper log generated from a well in Tuscaloosa Marine Shale (TMS) area. Compared with the ideal annulus, the model can provide an accurate recommendation for applying rock-based geopolymer in field conditions. The results aim to provide more information on the application and mud displacement performance of rock-based geopolymer in high-inclined and horizontal wells. Recommended additives were proposed for the optimization of pumpability and displacement efficiency. Evalua

关键词： Geopolymers

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Evaluation of Information Content in 2D and 3D Microstructural Characterization of Brush Particle-Based Hybrid materials 22

Evaluation of Information Content in 2D and 3D Microstructur...

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IS and T International Symposium on Electronic Imaging 2024: 22nd Computational Imaging, COIMG 2024

作者： Abdullah, Ayesha Ferguson, Kevin Drummy, Lawrence Kara, Levent Burak Bockstaller, Michael R. Carnegie Mellon University Department of Materials Science & Engineering PittsburghPA United States Carnegie Mellon University Department of Mechanical Engineering PittsburghPA United States Air Force Research Laboratory FairbornOH United States

In the field of polymers, 2D images are often used to discern information about the microstructure of bulk polymer materials. For brush particle assembly structures, this work evaluates microstructure information retrieved from different material characterization techniques for thin film (i.e., electron imaging of brush particle monolayers) and bulk materials (small angle X-ray scattering), respectively. The effect of confinement of polymer chains into thin (2D) films on the conformation of tethered chains is discussed and used to rationalize systematic discrepancies between characteristic nanoparticle spacings in thin films and bulk materials. An approach to rationalize bulk material properties based on thin film measurements is presented. © 2024, Society for Imaging science and Technology.

关键词： Microstructure

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ELECTROPHORETIC DEPOSITION OF CARBON NANOTUBES: TOWARDS ROLL-TO-ROLL MANUFACTURING AND NOVEL MULTIFUNCTIONAL COMPOSITE SENSORS 23

ELECTROPHORETIC DEPOSITION OF CARBON NANOTUBES: TOWARDS ROLL...

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23rd International Conference on Composite materials, ICCM 2023

作者： Sung, Dae Han Chaudhari, Amit Doshi, Sagar M. Thostenson, Erik T. Center for Composite Materials University of Delaware NewarkDE United States Department of Mechanical Engineering University of Delaware NewarkDE United States Department of Materials Science & Engineering University of Delaware NewarkDE United States

This research focuses on the utilization of electrophoretic deposition (EPD) as an innovative technique for integrating nanostructured films into fiber-based composites, resulting in the creation of multiscale smart textiles. The use of an aqueous dispersion system in EPD offers the potential for large-scale manufacturing, thanks to its advantageous features such as room temperature processing, absence of harsh chemicals, and flexibility in selecting substrate fabrics. In this study, carbon nanotubes (CNTs) that were functionalized with a cationic polymer were deposited onto various fabrics to assess their multifunctionality as piezo-resistive sensors for detecting human motion. By controlling EPD processing parameters like electric field and deposition time, the morphology of the CNT coatings on non-conductive fabrics could be customized due to the unique film formation mechanism. When incorporated into stretchable wearable woven fabrics, the CNTs formed a nanostructured conductive network, resulting in exceptional sensitivity for detecting arm bending and inhale/exhale motion. The resistance change observed reached up to 3000%. Furthermore, a laboratory-scale roll-to-roll pilot line was developed, enabling continuous fabrication of multifunctional textiles and industrialization of smart composites. The outcomes of this research demonstrate the significant potential of EPD-processed CNT-based resistive sensors in motion detection, robotics, and clinical device applications, particularly when combined with large-scale manufacturing capabilities. © 2023 International Committee on Composite materials. All rights reserved.

关键词： Carbon nanotubes

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Effect of Yttrium Treatment on Germanium-Oxide-Based Interfacial Layer of Ge P-Channel Metal–Oxide–Semiconductor Field-Effect Transistor Fabricated Through In Situ Plasma-Enhanced Atomic Layer Deposition

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IEEE Transactions on Electron Devices 2024年第3期71卷 1-6页

作者： Li, Hui-Hsuan Lin, Kuan-Yu Tsai, Yi-He Lin, Yu-Hsien Chien, Chao-Hsin Institute of Electronics National Yang Ming Chiao Tung University Hsinchu Taiwan Graduate Program for Nanotechnology Department of Materials Science and Engineering National Yang Ming Chiao Tung University Hsinchu Taiwan Department of Electronic Engineering National United University Miaoli Taiwan

This study investigated the effect of yttrium (Y) treatment on a germanium (Ge)-oxide-based interfacial layer (IL) through in situ plasma-enhanced atomic layer deposition (PEALD). Time-of-flight secondary-ion mass spectrometry revealed that the surface reaction and deposition could be successfully performed with a Y precursor, and X-ray photoelectron spectroscopy (XPS) revealed that Y treatment on an IL can suppress GeO

$_{\text{x}}$

volatilization. A metal–oxide–semiconductor capacitor gate-stack with a Y-GeO

$_{\text{x}}$

IL has a low leakage current density (2.1

$\times$

$^{-\text{5}}$

A/cm

$^{\text{2}}$

) and a low interface trap density (approximately 5.5

$\times$

$^{\text{11}}$

$^{-\text{1}}$

$^{-\text{2}}$

) under optimized temperatures. Moreover, the Ge P-channel metal–oxide–semiconductor field-effect transistor (P-MOSFET) containing a gate-stack with a Y-treated Ge-oxide-based IL exhibited a high I

$_{\biosc{on}}$

$_{\biosc{off}}$

ratio and low OFF-state current. Therefore, applying the proposed Y treatment on the IL of a Ge P-MOSFET can help achieve a subnanometer equivalent oxide thickness (EOT) and an

关键词： Ge-oxide-based germanium germanium oxide (GeOx) in situ interfacial layer (IL) plasma-enhanced atomic layer deposition (PEALD) Y-GeOx yttrium

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Accelerating self-consistent field iterations in Kohn-Sham density functional theory using a low-rank approximation of the dielectric matrix

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Physical Review B 2023年第12期107卷 125133-125133页

作者： Sambit Das Vikram Gavini Department of Mechanical Engineering and Department of Materials Science and Engineering University of Michigan Ann Arbor Michigan 48109 USA

We present an efficient preconditioning technique for accelerating the fixed-point iteration in real-space Kohn-Sham density functional theory (DFT) calculations. The preconditioner uses a low-rank approximation of the dielectric matrix (LRDM) based on Gâteaux derivatives of the residual of fixed-point iteration along appropriately chosen direction functions. We develop a computationally efficient method to evaluate these Gâteaux derivatives in conjunction with the Chebyshev filtered subspace iteration procedure, an approach widely used in large-scale Kohn-Sham DFT calculations. Further, we propose a variant of LRDM preconditioner based on adaptive accumulation of low-rank approximations from previous self-consistent field iterations, and also extend the LRDM preconditioner to spin-polarized Kohn-Sham DFT calculations. We demonstrate the robustness and efficiency of the LRDM preconditioner against other widely used preconditioners on a range of benchmark systems with sizes ranging from ∼100 to 1100 atoms (∼500–20 000 electrons). The benchmark systems include various combinations of metal-insulating-semiconducting heterogeneous material systems, nanoparticles with localized d orbitals near the Fermi energy, nanofilm with metal dopants, and magnetic systems. In all benchmark systems, the LRDM preconditioner converges robustly within 20–30 iterations. In contrast, other widely used preconditioners show slow convergence in many cases, as well as divergence of the fixed-point iteration in some cases. Finally, we demonstrate the computational efficiency afforded by the LRDM method, with up to 3.4-fold reduction in computational cost for the total ground-state calculation compared to other preconditioners.

关键词： Electronic structure First-principles calculations Density functional theory

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MATHEMATICAL MODELING CONCERNING CERAMIC COMPACTION DURING A CLAY MASS PRESSING PROCESS

International Journal of Mechatronics and Applied Mechanics

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International Journal of Mechatronics and Applied Mechanics 2024年第15期2024卷 113-119页

作者： Shakirov, Shukhrat Bektemirov, Begali Sadaddinova, Sanobar Umirov, Ulugbek Tilavov, Yunus Materials Science department Tashkent State Technical University Uzbekistan Higher Mathematics department Tashkent University of Information Technologies Named After Muhammad Al-Khwarizmi Uzbekistan Mechanical Engineering department Almalyk branch of Tashkent State Technical University Uzbekistan Karshi State University Karshi Uzbekistan

In this article, a mathematical model was developed that determines the geometric and kinematic parameters of the clay mass pressing process based on the properties of the components that make up the clay mass and their initial maximum compressibility in the pressing of cylindrical ceramic products from clay masses. This mathematical model allows carrying out analytical calculations of the current compressibility, relative porosity, and current density of the clay mass depending on the size of the chamber of matrix of the press mold, the current and final displacement values of the punch and also pre-planning the geometric parameters of the press mold based on the initial properties of the clay mass. © 2024, Cefin Publishing House. All rights reserved.

关键词： Porosity

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Efficacy of Fleurya aestuans on Mild Steel Protection in Acidic Systems: Combined Gravimetry, Gasometry, and Electrochemical Evaluations

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Journal of Bio- and Tribo-Corrosion 2024年第2期10卷 1-15页

作者： Obike, Anthony I. Udorji, Franklin I. Ekerenam, Okpo O. Emori, Wilfred Onyeije, Ugomma C. Onyedinma, Ukaogo P. Okonkwo, Paul C. Ikeuba, Alexander I. Department of Pure and Industrial Chemistry Abia State University Uturu Nigeria Department of Biochemistry School of Pure & ampApplied Sciences Federal University of Technology Ikot Abasi Nigeria School of Materials Science and Engineering Sichuan University of Science and Engineering Sichuan Zigong643000 China Key Laboratory of Material Corrosion and Protection of Sichuan Province Sichuan Zigong643000 China Department of Pure and Industrial Chemistry Nnamdi Azikiwe University Awka Nigeria Mechanical and Mechatronics Engineering Dhofar University Salalah Oman Materials Chemistry Research Group Department of Pure and Applied Chemistry University of Calabar Calabar Nigeria

The anticorrosion studies of Fleurya aestuans extract on mild steel in acidic media was carried out in 2 M HCl and 1 M H2SO4 using gasometric, gravimetric, and electrochemical techniques at room temperature and at elevated temperatures (303 and 323 K). In all test settings, the inhibitory effectiveness changed in direct proportion to the extract concentration and in inverse proportion to the exposure duration and temperature. The anticorrosion potential of the extract is attributed to the adsorption of its phytoconstituents on the metal surface, blocking the active corrosion sites on mild steel. The adsorption mechanism conformed to the Langmuir, Freundlich, and Temkin adsorption isotherm models with the best fits recorded for the Langmuir model (R2 of 0.9777 and 0.9850 in HCl and H2SO4, respectively). The calculated thermodynamic parameters, namely Gibbs free energy (∆Goads), activation energy (Ea), and heat of adsorption (Qads) all favored a spontaneous and exothermic physical adsorption reaction mechanism of the extract. Potentiodynamic polarization experiments revealed that the extract displayed mixed-type corrosion suppression ability and electrochemical impedance spectroscopy (EIS) evaluations showed increasing charge transfer resistance with increasing extract concentration. Moreover, scanning electron microscopy examinations disclosed the presence of a protective covering on the surface of mild steel coupons in the acid solutions containing F. aestuans extract. The outcomes of the several tests show strong correlations with one another. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.

关键词： Adsorption

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Electrochemical Corrosion Behavior and mechanical Response of Selective Laser Melted Porous Metallic Biomaterials

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Acta Metallurgica Sinica(English Letters) 2023年第8期36卷 1235-1246页

作者： Kai Hu Lei Zhang Yuanjie Zhang Bo Song Shifeng Wen Qi Liu Yusheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Department of Mechanical Engineering City University of Hong KongTat Chee AvenueKowloonHong KongChina AVIC Manufacturing Technology Institute Science and Technology on Power Beam Processes LaboratoryBeijing Key Laboratory of High Power Beam Additive Manufacturing Technology and EquipmentAeronautical Key Laboratory for Additive Manufacturing TechnologiesBeijing100024China

The porous metallic biomaterials have attracted significant attention for implants because their lower young's modulus matches the human bones, which can eliminate the stress shielding effect and facilitate the growth of bone tissue cells. The porous metallic biomaterials fabricated by selective laser melting (SLM) have broad prospects, but the surface of the SLM-built porous structure has been severely adhered with unmelted powders, which affects the forming accuracy and surface quality. The porous metallic biomaterials face the corrosion problem of complex body fluid environments during service, so their corrosion resistance in the human body is extremely important. The surface quality will affect the corrosion resistance of the porous metallic biomaterials. Therefore, it is necessary to study the effect of post-treatment on the corrosion resistance of SLMed samples. In this work, the mechanical response and the electrochemical corrosion behavior in simulated body fluid of diamond and pentamode metamaterials Ti-6Al-4V alloy fabricated by SLM before and after sandblasting were studied. After sandblasting, the mechanical properties of the two porous metallic biomaterials were slightly improved, and the self-corrosion potential and pitting potential were more negative;meanwhile, the self-corrosion current density and passive current density increased, indicating that its corrosion performance decreased, and the passive film stability of sandblasted samples got worse.

关键词： Selective laser melting Porous metallic biomaterials mechanical behavior Electrochemical corrosion behavior Ti-6A1-4V

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Effect of electrolyte anions on the cycle life of a polymer electrode in aqueous batteries

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escience 2022年第1期2卷 110-115页

作者： Ye Zhang Lihong Zhao Yanliang Liang Xiaojun Wang Yan Yao Department of Electrical and Computer Engineering Materials Science and Engineering ProgramUniversity of HoustonHoustonTX77204USA Texas Center for Superconductivity at the University of Houston HoustonTX77204USA

Redox polymers are a class of high-capacity, low-cost electrode materials for electrochemical energy storage, butthe mechanisms governing their cycling stability are not well understood. Here we investigate the effect of anionson the longevity of a p-dopable polymer through comparing two aqueous zinc-based electrolytes. Galvanostaticcycling studies reveal the polymer has better capacity retention in the presence of triflate anions than that withsulfate anions. Based on electrode microstructural analysis and evolution profiles of the cell stacking pressure, theorigin of capacity decay is ascribed to mechanical fractures induced by volume change of the polymer activematerials during repeated cycling. The volume change of the polymer with the triflate anion is 61% less than thatwith the sulfate anion, resulting in fewer cracks in the electrodes. The difference is related to the different anionsolvation structures—the triflate anion has fewer solvated water molecules compared with the sulfate anion,leading to smaller volume expansion. This work highlights that anions with low solvation degree are preferablefor long-term cycling.

关键词： Aqueous batteries Polymer electrode Anions Volume chang

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