We synthesized anion exchange polymers by a reaction of chloromethylated poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) with strongly basic 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). TBD contains secondary and tertiary amine groups in the guanidine portion. To favor the functionalization with the secondary amine, TBD was activated with butyl lithium. The yield of amine formation via the reaction of the benzyl chloride moiety with TBD was 85%. Furthermore, we prepared polymers with quaternary ammonium groups by the reaction of PPO-TBD with CHI. The synthesis pathways and ionomer structure were investigated by NMR spectroscopy. The thermal decomposition of both ionomers, studied by thermogravimetry, started above 200 °C, corresponding to the loss of the basic group. The ion exchange capacities, water uptake and volumetric swelling are also reported. The "intrinsic" anion conductivity of PPO-TBD due to the dissociation of grafted TBD was in the order of 1 mS/cm (Cl form). The quaternized ionomer (PPO-TBD-Me) showed an even larger ionic conductivity, above 10 mS/cm at 80 °C in fully humidified conditions.
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http://dx.doi.org/10.3390/membranes9050057 | DOI Listing |
Adv Sci (Weinh)
December 2024
Institute of Materials Science, Technische Universität Darmstadt, Peter-Grünberg-Str. 2, D-64287, Darmstadt, Germany.
The design of cathode/electrolyte interfaces in high-energy density Li-ion batteries is critical to protect the surface against undesirable oxygen release from the cathodes when batteries are charged to high voltage. However, the involvement of the engineered interface in the cationic and anionic redox reactions associated with (de-)lithiation is often ignored, mostly due to the difficulty to separate these processes from chemical/catalytic reactions at the cathode/electrolyte interface. Here, a new electron energy band diagrams concept is developed that includes the examination of the electrochemical- and ionization- potentials evolution upon batteries cycling.
View Article and Find Full Text PDFChem Sci
December 2024
College of Chemistry and Chemical Engineering, Chongqing University Chongqing 401331 China
Oxygen vacancies in Ruddlesden-Popper (RP) perovskites (PV) [AO][ABO] play a pivotal role in engineering functional properties and thus understanding the relationship between oxygen-vacancy distribution and physical properties can open up new strategies for fine manipulation of structure-driven functionalities. However, the structural origin of preferential distribution for oxygen vacancies in RP structures is not well understood, notably in the single-layer ( = 1) RP-structure. Herein, the = 1 RP phase SrNdZnO was rationally designed and structurally characterized by combining three-dimensional (3D) electron diffraction and neutron powder diffraction.
View Article and Find Full Text PDFJ Phys Chem B
December 2024
Department of Chemistry, Eszterházy Károly Catholic University, Leányka utca 12, H-3300 Eger, Hungary.
In this work, we carry out a systematic computer simulation investigation of the single particle dynamics at the free surface of imidazolium-based room temperature ionic liquids by applying intrinsic surface analysis. Besides assessing the effect of the potential model and temperature, we focus in particular on the effect of changing the anion type, and, hence, their shape and size. Further, we also address the role of the length of the cation alkyl chains, known to protrude into the vapor phase, on the surface dynamics of the ions.
View Article and Find Full Text PDFJ Am Chem Soc
December 2024
School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P.R. China.
Piezoionic materials have attracted considerable attention for their ability to generate iontronic signals or power in response to stress stimuli. However, the limited intrinsic transport distinction between cations and anions within most ionic materials results in weakened iontronic power conversion efficiencies under stress fields. Here, we report a piezoheterogated biphasic gel for ultrahigh iontronic generation, characterized by high-internal microphase heterointerfaces that facilitate the distinct transport of various ion species.
View Article and Find Full Text PDFJ Phys Chem Lett
December 2024
School of Integrated Circuit Science and Engineering, Tianjin Key Laboratory of Film Electronic and Communication Devices, Tianjin University of Technology, Tianjin 300384, China.
Advancing the development of novel materials or architectures for random access memories, coupled with an in-depth understanding of their intrinsic conduction mechanisms, holds the potential to transcend the conventional von Neumann bottleneck. In this work, a novel memristor based on the Sb(S,Se) material with an alloy of S and Se was fabricated. A systematic investigation of the correlation between the Se/(S + Se) ratio and memristive performance revealed that Ag/Sb(S,Se)/FTO memristive behavior is uniquely associated with the formation and disruption of anion vacancies and silver filaments.
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