Based on a previously developed polyamide proton conductive macromolecule, the nano-scale structure of the self-assembled proton conductive channels (PCCs) is adjusted via enlarging the nano-scale pore size within the macromolecules. Hyperbranched polyamide macromolecules with different size are synthesized from different monomers to tune the nano-scale pore size within the macromolecules, and a series of hybrid membranes are prepared from these two micromoles to optimize the PCC structure in the proton exchange membrane. The optimized membrane exhibits methanol permeability low to 2.2 × 10 cm²/s, while the proton conductivity of the hybrid membrane can reach 0.25 S/cm at 80 °C, which was much higher than the value of the Nafion 117 membrane (0.192 S/cm). By considering the mechanical, dimensional, and the thermal properties, the hybrid hyperbranched polyamide proton exchange membrane (PEM) exhibits promising application potential in direct methanol fuel cells (DMFC).
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6418661 | PMC |
| http://dx.doi.org/10.3390/polym9120703 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Bimetallic constrained aluminum alkoxide complexes for ring-opening polymerization of cyclic esters: activity enhancement cationic activation.
Dalton Trans
January 2025
Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan, Rayong 21210, Thailand.
Dinuclear aluminum complexes bearing a constrained 'indanimine' ligand based on a short hydrazine bridge were synthesized. Single-crystal X-ray crystallography reveals bimetallic penta-coordinated aluminum centers having a distorted trigonal bipyramidal geometry. A short Al-Al distance of 4.
View Article and Find Full Text PDFTime-resolved spectroscopy uncovers deprotonation-induced reconstruction in oxygen-evolution NiFe-based (oxy)hydroxides.
Nat Commun
January 2025
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, PR China.
Transition-metal layered double hydroxides are widely utilized as electrocatalysts for the oxygen evolution reaction (OER), undergoing dynamic transformation into active oxyhydroxides during electrochemical operation. Nonetheless, our understanding of the non-equilibrium structural changes that occur during this process remains limited. In this study, utilizing in situ energy-dispersive X-ray absorption spectroscopy and machine learning analysis, we reveal the occurrence of deprotonation and elucidate the role of incorporated iron in facilitating the transition from nickel-iron layered double hydroxide (NiFe LDH) into its active oxyhydroxide.
View Article and Find Full Text PDFDesigning High Content Carbonylated β-Cyclodextrin/PBI Mixed Matrix Membrane as HT-PEM to Reduce HPO Loss.
Langmuir
January 2025
Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang, 414000 Hunan, P. R. China.
The high-temperature proton exchange membranes suffer from weak binding strength for phosphoric acid molecules, which seriously reduce the fuel cell efficiency, especially operation stability. Introduction of microporous material in the membrane can effectively reduce the leaching of phosphoric acid. However, due to the poor compatibility between the polymer and fillers, the membrane's performance significantly reduced at high fillers content.
View Article and Find Full Text PDFComputational Explorations of Th First Hydrolysis Reaction Constants: Insights from Molecular Dynamics and Density Functional Theory Calculations.
J Phys Chem A
January 2025
Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education, Tsinghua University, Beijing 100084, China.
The fundamental hydrolysis behavior of tetravalent actinide cations (An) with a high charge is crucial for understanding their solution chemistry, particularly in nuclear fuel reprocessing and environmental behavior. Using Th as a reference of the An series, this work employed both the periodic model and the cluster model to calculate the first hydrolysis reaction constant (p) of the Th aqua ion and conducted a detailed evaluation of these approaches. In the periodic model, molecular dynamics (AIMD) simulations of Th in the explicit solvation environment are conducted, using metadynamics and constrained molecular dynamics to calculate p values.
View Article and Find Full Text PDFNucleophilic and Electrophilic Molybdenum Terminal Oxo Complexes by Coordination-Induced Bond Weakening of Hydroxo O-H Bonds.
Inorg Chem
January 2025
Department of Chemistry, University of Calgary, 2500 University Dr. NW, T2N 1N4 Calgary, AB Canada.
The extent of coordination-induced bond weakening in aquo and hydroxo ligands bonded to a molybdenum(III) center complexed by a dianionic, pentadentate ligand system was probed by reacting the known complex (BPzPy)Mo(III)-NTf, , with degassed water or dry lithium hydroxide. The aquo adduct was not observed, but two LiNTf-stabilized hydroxo complexes were fully characterized. Computational and experimental work showed that the O-H bond in these complexes was significantly weakened (to ≈57 kcal mol), such that these compounds could be used to form the diamagnetic, neutral terminal molybdenum oxo complex (BPzPy)Mo(IV)O, , by hydrogen atom abstraction using the aryl oxyl reagent ArO• (Ar = 2,4,6-tri--butylphenyl).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!