Article
Chemistry, Physical
Congfan Zhao, Shu Yuan, Xiaojing Cheng, Lu An, Jiazhen Li, Shuiyun Shen, Jiewei Yin, Xiaohui Yan, Junliang Zhang
Summary: The study investigates the influence of equivalent weight (EW) and side-chain length of perfluorosulfonic acid (PFSA) ionomers on the membrane electrode assemblies (MEAs) of proton exchange membrane water electrolyzers (PEMWEs). It is found that the change in PFSA ionomer EWs affects the surface wettability and MEA performance, resulting in a voltage difference due to changed mass transport overpotential.
JOURNAL OF POWER SOURCES
(2023)
Article
Mechanics
Vineet Nair, Ishan Sharma, V. Shankar
Summary: In this study, the equilibrium of an axisymmetric system of sessile and pendent drops on pre-stretched nonlinear elastic membranes is investigated. The non-unique equilibrium solutions due to force balance alone are shown, and the uniqueness of the equilibrium solution is determined by requiring the continuity of meridional stretches across the three-phase contact circle. The equilibrium configurations of the drop-membrane system are computed for a range of drop volumes and membrane pre-tensions using a special class of nonlinear elastic materials - I2 materials. This work enables applications such as using the system as an elastocapillary probe for membrane pre-tension and suggesting an experimental protocol for measuring the membrane's surface properties.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Stefano Sirotti, Matteo Pelliciari, Angelo Aloisio, Angelo Marcello Tarantino
Summary: This study proposes an analytical formula to compute the pressure-deflection curves of pre-stretched circular membranes. The formula is calibrated by fitting numerical solutions and can be used for both compressible and incompressible materials. A code is available for computing the formula.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Chemistry, Physical
Chang Jin Lee, Jaeheon Song, Kyung Seok Yoon, Yecheol Rho, Duk Man Yu, Keun-Hwan Oh, Jang Yong Lee, Tae-Ho Kim, Young Taik Hong, Hyung-Joong Kim, Sang Jun Yoon, Soonyong So
Summary: This study focuses on improving the performance and durability of perfluorinated sulfonic acid membranes for polymer electrolyte membrane water electrolysis by controlling the membrane microstructure. The stretched and thinned Nafion membrane shows better cell performance and durability, with reduced ohmic resistance and enhanced interfacial stability.
JOURNAL OF POWER SOURCES
(2022)
Article
Mechanics
Vineet Nair, Ishan Sharma
Summary: We study the equilibrium of planar systems consisting of sessile and pendent drops on pre-stretched, nonlinear elastic membranes. The membrane experiences large deformations due to both capillary forces and the drop's weight. The membrane's surface energies are allowed to depend upon stretches in the membrane. We solve these coupled nonlinear equations to obtain the global equilibria of the drop-membrane system, and report the effects of drop's volume and membrane's pre-tension on the system's geometry and tension distribution in the membrane.
Article
Nanoscience & Nanotechnology
Zhi Long, Kenji Miyatake
Summary: Researchers have developed a novel sulfonated polyphenylene membrane for high-temperature and low-humidity operation of proton exchange membrane fuel cells (PEMFCs), demonstrating superior proton conductivity and catalytic activity. The membrane achieved a high power density of 390 mW cm(-2) at 120 degrees Celsius and 30% relative humidity, with confirmed durability under accelerated degradation conditions for 1000 hours.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Wei Yuan, Lingping Zeng, Ying Li, Jianchuan Wang, Xi Wang, Qiang Liao, Li Li, Zidong Wei
Summary: In this study, composite anion exchange membranes (AEMs) based on ultrahigh molecular weight polyethylene (UHMWPE) were successfully prepared by in situ bulk polymerization. The as-prepared composite membranes exhibited super high strength, ultrathin thickness, and excellent properties including low permeation, low water uptake, low dimensional swelling, high conductivity and good alkaline stability. Moreover, the fuel cell performance based on the ultrathin composite AEMs showed outstanding peak power density and good short-term durability.
Article
Chemistry, Physical
Wanjie Song, Xian Liang, Huaqing Zhang, Xiang Liu, Xin Zhang, Liang Wu, Xiaolin Ge, Tongwen Xu
Summary: In this study, a freestanding ultrathin AEM with excellent mechanical strength and ionic conductivity was successfully fabricated, which is suitable for improving the performance of alkaline anion exchange membrane fuel cells.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Engineering, Electrical & Electronic
Peng-Fa Li, Shi-Wei Qu, Shiwen Yang, Ming Jiang, Jun Hu
Summary: This article derives formulas for calculating phased array scattering fields under oblique incidences, providing a theoretical basis for reducing scattering sidelobe levels (SLL). Additionally, a method is proposed to compute and evaluate the array impedance matching performance based on an equivalent network model, aiming to improve antenna radiation performance. Numerical study validates the accuracy and efficiency of the formulas in predicting array scattering fields and reflection coefficients. Furthermore, a microstrip phased array antenna with a tapered array shape and optimized element feed networks is designed, employing a modified particle swarm optimization algorithm to search for solutions that simultaneously reduce monostatic scattering SLL and improve antenna impedance matching. The optimized phased array antenna achieves an 8.8 dB reduction in scattering SLL in the angular range of 10 degrees-30 degrees and operating band of 5.5-7.5 GHz compared to its conventional counterpart, while also improving impedance matching and slightly increasing gains. The numerical results are well validated through experiments.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Chemical
Parthapratim Bera, Jaladhi S. Trivedi, Suresh K. Jewrajka
Summary: Double network thin film composite (TFC) nanofiltration membranes were prepared by in situ interfacial polymerization, showing enhanced rejection towards heavy metal ions and organic solutes and improved fouling resistance compared to conventional TFC membranes.
Article
Chemistry, Physical
Yajie Wang, Yannan Wang, Maolian Guo, Tao Ban, Xiuling Zhu
Summary: In this study, a design strategy for anion exchange membranes (AEMs) incorporating ether-bond free and piperidinium cationic groups was proposed to enhance chemical stability. A series of poly (isatin-piperidium-terphenyl) based AEMs were synthesized, and the effect of functionalization on their performance was investigated. The results showed that the introduction of N-propargylisatin resulted in high molecular weight polymers with robust mechanical properties and adjustable ion exchange capacity (IEC). The AEMs also exhibited improved dimensional stability and high OH- conductivity. The alkali-stabilized AEM demonstrated excellent OH- conductivity retention after prolonged exposure to NaOH. Furthermore, the direct borohydride fuel cells (DBFC) with the AEM membrane as a separator exhibited promising performance. This work highlights the potential of poly (isatin-N-dimethyl piperidinium triphenyl) as an AEM for fuel cells.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Panpan Guan, Jianlong Lei, Yecheng Zou, Yongming Zhang
Summary: The addition of Ti3C2Tx filler into the SSC PFSA membrane significantly enhances proton conductivity, reduces hydrogen permeation, and improves thermo-mechanical properties, making the composite membrane a potential material for PEM fuel cells operating above the water boiling temperature.
Article
Mathematics, Interdisciplinary Applications
T. Liu, W. Zhang, Y. Zheng, Y. F. Zhang
Summary: This study investigates the nonlinear vibrations of a large deployable space antenna (LDSA) subjected to thermal load with 1:3 internal resonance. The frequencies of LDSA are analyzed and a threefold relationship between different frequencies is discovered. The thermal load significantly influences the stability of LDSA, as shown by the amplitude-frequency response curves.
CHAOS SOLITONS & FRACTALS
(2021)
Article
Chemistry, Physical
Sandip Pal, Arani Choudhury, Pratyush Patnaik, Suman Sarkar, Uma Chatterjee
Summary: The objective of this work is to prepare functional copolymer/GO composite membranes by a simple and cost-effective method, and evaluate their structural, thermal, mechanical, and fuel cell performance. The results show that the addition of GO significantly enhances the mechanical properties and thermal stability of the composite membranes, while maintaining low methanol permeability and high ion conductivity.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Review
Chemistry, Physical
Sahng Hyuck Woo, So Young Lee, Young-Gi Yoon, Arnaud Rigacci, Jung-Je Woo, Christian Beauger, Hyoung-Juhn Kim
Summary: The incorporation of nanoclays into polymer matrixes improves the performance of proton exchange membranes (PEMs) in proton exchange membrane fuel cells (PEMFCs), especially at high temperatures and low relative humidity (RH). Nanoclays also enhance the mechanical properties and reduce the cost of composite membranes.
JOURNAL OF POWER SOURCES
(2022)
Review
Materials Science, Ceramics
Fabricio Eduardo Bortot Coelho, Giuliana Magnacca, Vittorio Boffa, Victor M. Candelario, Mieke Luiten-Olieman, Wenjing Zhang
Summary: Zirconia (ZrO2) membranes have gained popularity due to their superior chemical resistance and hydrophilicity compared to silica and alumina. They are widely used in various industries for producing drinking water, treating wastewater, and in petrochemical, food, and beverages industries. However, fabricating ZrO2 membranes for advanced filtration and gas separation is still challenging.
CERAMICS INTERNATIONAL
(2023)
Article
Engineering, Environmental
Dan Zhao, Maria Louise Leth, Maher Abou Hachem, Iram Aziz, Natalija Jancic, Thomas Luxbacher, Claus Helix-Nielsen, Wenjing Zhang
Summary: Biocatalytic nanofibrous membranes have efficient catalytic performance and operational catalytic stability in wastewater treatment. The fabrication of flexible SiO2 biocatalytic nanofiber membranes and their application in emerging pollutant bioremediation have been reported. The membranes showed high enzyme immobilization yield and maintained residual activity after multiple cycles.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Green & Sustainable Science & Technology
Guan Wang, Kai Tang, Yuechao Yao, Wenjing (Angela) Zhang, Henrik Rasmus Andersen, Yifeng Zhang
Summary: In this study, the introduction of granular sludge into the biocathode of a microbial electrolysis cell (MEC) improved the regeneration rate of Fe(II) from actual ferric sludge at near neutral pH. The wastewater constituents served as the reducing power to regenerate Fe(II). A high regeneration rate of 175 mg/L dissolved Fe(II) was achieved in the flow-through biocathode.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Chemistry, Multidisciplinary
Oguz Gozcu, H. Utkucan Kayaci, Yibo Dou, Wenjing Zhang, Niklas Hedin, Alma B. Jasso-Salcedo, Andreas Kaiser, Simge Cinar Aygun
Summary: This study investigated the colloidal characteristics of submicron-sized zeolite NaA in mixed ethanol-water solvents. The effects of solvent mixing ratio and various additives on zeolite dispersion were studied. Zeolite NaA particles became unstable in solvent mixtures with a high ethanol-to-water ratio, and the destabilization was explained by the DLVO theory. Improved stabilization of zeolite NaA suspensions was achieved in ethanol-rich solvent mixtures using nonionic low molecular weight organic additives, particularly PEG-400.
Article
Chemistry, Multidisciplinary
Jibo Qin, Yibo Dou, Jianchi Zhou, Victor M. Candelario, Henrik Rasmus Andersen, Claus Helix-Nielsen, Wenjing Zhang
Summary: The conversion of waste plastic into high-value-added chemicals is considered a promising approach to address global plastic pollution and promote the circular economy. This study developed a partial calcination strategy to create a zinc oxide/UiO66-NH2 heterojunction for photocatalytic valorization of plastic. The obtained heterojunction exhibited high activity for converting polylactic acid and polyvinyl chloride into acetic acid, along with hydrogen production. This work provides insights into the process of photocatalytic valorization of plastic and offers a feasible strategy for designing heterojunction photocatalysts.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Zhongtao Ma, Waynah Lou Dacayan, Christodoulos Chatzichristodoulou, Kristian Speranza Molhave, Francesco Maria Chiabrera, Wenjing Zhang, Soren Bredmose Simonsen
Summary: The combination of electrical impedance spectroscopy (EIS) and environmental transmission electron microscopy (ETEM) is demonstrated by testing a specially designed micro gadolinia-doped ceria (CGO) sample. The EIS-TEM method provides valuable information on the structural and compositional aspects relevant to electrochemical performance. The developed platform is important for understanding nanoscale processes in green energy technologies.
Article
Engineering, Environmental
Feiyan Wu, Yibo Dou, Jianchi Zhou, Jibo Qin, Tao Jiang, Yuechao Yao, Claus Helix-Nielsen, Wenjing Zhang
Summary: This study reports a feasible strategy for synthesizing high-entropy photocatalysts-based fibrous membranes with a dual function of capturing and upcycling plastic. The researchers found that polyacrylonitrile nanofiber templates enable the growth of highly arranged high-entropy metal tungstates (FeCoNiCuZn)WO4, and the lattice distortion in XWO4 modulates the band gap structure, leading to enhanced upgradability of captured polylactic acid. This research provides important insights into tailoring the structure and composition of high-entropy photocatalysts for plastic upcycling.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Feiyan Wu, Changming Li, Yibo Dou, Jianchi Zhou, Tao Jiang, Yuechao Yao, Na Yeon Lee, Sung Yul Lim, Claus Helix-Nielsen, Wenjing Zhang
Summary: This study uses subnano-sized platinum-based photocatalysts to effectively convert plastic waste into high-value chemicals, such as acetic acid and formic acid. The research provides insight into the rational design of efficient photocatalysts for plastic upcycling and offers a useful solution to waste management and environmental sustainability challenges.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Iram Aziz, Xing Chen, Xuhui Hu, Wenjing (Angela) Zhang, Rabiya Javed Awan, Ali Rauf, Salman Noshear Arshad
Summary: There is a need for the design of economical, large-scale, stable, and highly active bifunctional electrocatalysts for Zn-air batteries with enhanced oxygen reduction and oxygen evolution performance. In this study, a series of electrocatalysts were fabricated by the in situ formation of bimetallic nanoparticles aiding in the growth of carbon nanotubes over carbon nanofibers during thermal treatment. The FeNi-CNT@CNF catalyst exhibited greatly improved bifunctional catalytic activity for both oxygen reduction and evolution reactions, as well as superior stability compared to benchmark materials.
Article
Chemistry, Inorganic & Nuclear
Yuechao Yao, Zhangjian Li, Yibo Dou, Tao Jiang, Jizhao Zou, Sung Yul Lim, Poul Norby, Eugen Stamate, Jens Oluf Jensen, Wenjing Zhang
Summary: High entropy alloys (HEAs) have attracted significant attention in the field of electrocatalysis due to their tunable alloy composition and synergistic effects between different metals. However, their potential is limited by inefficient and unscalable fabrication methods. This study proposes a novel solid-state thermal reaction method to synthesize HEA nanoparticles encapsulated in an N-doped graphitized hollow carbon tube. The synthesized HEA nanoparticles are confined by the graphitized hollow carbon tube, which can prevent the aggregation of alloy particles during the oxygen reduction reaction (ORR). The HEA catalyst FeCoNiMnCu-1000(1:1) exhibits promising performance in a 0.1 M KOH solution, demonstrating potential applications in energy storage and conversion.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Jibo Qin, Yibo Dou, Jianchi Zhou, Dan Zhao, Tobias Orlander, Henrik Rasmus Andersen, Claus Helix-Nielsen, Wenjing Zhang
Summary: This study presents a method of combining carbon nanodots with metal-organic frameworks for the photocatalytic upcycling of polyvinyl chloride (PVC) waste. The fabricated CDs/Zr-MOF catalyst exhibits high activity and yield in PVC conversion, while providing insights into the key roles in the reaction mechanism. This work offers a new approach for fabricating nanoparticle-embedded MOF-based photocatalysts and is of great significance for the chemical upcycling of plastics.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Thermodynamics
Xuhang Shi, Fuqiang Wang, Yaping Fan, Jintao Song, Jie Xu, Ziming Cheng, Wenjing Zhang
Summary: This study proposes a novel method of ordering radiation regulation of foam structural catalyst, which can improve the efficiency of solar to fuel conversion.
ENERGY CONVERSION AND MANAGEMENT
(2023)