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Poly(vinylphosphonic acid)-imidazole (PVPA-xIm) exhibits high proton conductivity above 100 °C. The high proton conductivity of PVPA-2Im depends on the molecular motions of Im. Molecular dynamics simulations conducted herein showed that the intercalation of Im and imidazolium into PVPA reduces the translational motion of Im in PVPA-2Im. The activation energy of the internal motion of Im is lower than that of the translational motion, indicating that proton conduction in PVPA-2Im occurs via a Grotthuss-type mechanism. [ABSTRACT FROM AUTHOR]

Protonic solid oxide fuel cells (P-SOFCs) have garnered significant attention due to their high power density and efficiency in operating at 400–700 oC. The development of high-performance cathode materials, characterized by excellent proton, oxide-ion, and electron conductivity, catalytic activity for oxygen reduction reaction, and long-term stability, is essential and urgently needed for realizing high-efficiency P-SOFCs. Recently, machine learning (ML) has emerged as a powerful tool in materials science, playing a central role in transitioning away from traditional approaches for developing new materials. In this review, recent advances of high-performance cathodes are summarized, and the challenges associated with their developments are highlighted. Furthermore, the potential ML-guided perspectives in terms of predicting proton, oxide-ion, and electron conductivity, catalytic activity, hydration ability, and stability for addressing these challenges are detailedly discussed, providing insights into the design and optimization of high-performance cathodes. Finally, the difficulties faced are presented for better utilization of ML in developing high-performance cathodes. In a word, this review not only presents the latest advances and challenges in high-performance cathodes for P-SOFCs but also highlights the promising role of ML in guiding their development. [Display omitted] • Machine learning guided perspectives in developing high-performance cathodes. • Proton uptake and conduction mechanisms in oxides. • The advances and challenges in developing high-performance cathodes. [ABSTRACT FROM AUTHOR]

Abstract Inspired by the parallel performing of storage and processing information in biological synapse, artificial synapse that can control ionic and protonic currents are ideal means for attracted tremendous attention as a promising option to break the von Neumann bottleneck. Here we demonstrate an artificial synapse with tunable synaptic behavior based on solution-processed two-dimensional (2D) C 3 N/polyvinylpyrrolidone (PVPy). The proton modulated memristive characteristics of synaptic device are verified by ambient pressure X-ray photoelectron spectroscopy under different H 2 O gas atmosphere. The highly proton conducting of C 3 N/PVPy matrix stems from the hydrogen bonding network between C 3 N and PVPy, as well as the large amount of ordered nitrogen atoms in C 3 N. The artificial synapse ensure a direct imitation of short-term and long-term plasticity in biological synapses including excitatory post-synaptic current (EPSC), paired-pulse facilitation (PPF), paired-pulse depression (PPD), PPF following PPD and post-tetanic potentiation (PTP). The C 3 N/PVPy matrix-based memristor which can mimic the synapse cleft based on proton conducting mechanism may find further applications in artificial intelligence. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

The development of proton exchange membranes (PEMs) with excellent performance becomes an important issue for proton exchange membrane fuel cells (PEMFCs). Acid–base hybrid high-temperature PEMs were prepared from aminopropyltriethoxysilane (APTES) and amino trimethylene phosphonic acid (ATMP) by sol–gel process. Fourier-transform infrared (FTIR) spectra revealed that phosphonic acid and amino group could have been protonized, and siloxane groups were hydrolysed and condensed to yield Si–O–Si network. These membranes were thermally stable up to 200°C and showed excellent dimensional stability in water. In addition, SEM analysis revealed that many nanoparticles appeared in the membranes, and energy dispersive spectrum (EDS) results proved that many phosphate ionswere present on the surface of the nanoparticles. This phenomenon became obvious with increasing acidity of sol in sol–gel process. Proton conductivity results indicated that the above structure was favourable for the formation of hydrogen bond and the proton conductivity increases with the increase in temperature, the highest conductivity can reach 4.93 × 10− 2 S cm− 1at 140°C under anhydrous condition. [ABSTRACT FROM PUBLISHER]

Abstract: Ba2(Zn1-xMx)2O6-δ (M = W, Nb) systems, where the oxygen vacancy concentration can be controlled by the Zn/M ratio, were found to have cubic double-perovskite-type structure for M = W and cubic perovskite-type structure for M=Nb. As it was found by thermogravimetry that the Ba2(Zn1-xMx)2O6-δ samples can uptake the large amount of H2O, we expected that the adsorption of H2O may contribute to a generation of proton conduction. Then, the electrical conductivity was measured in dry and humid Ar atmospheres by the two-probe method. The electrical conductivity remarkably increased in the humid atmosphere, suggesting occurrence of the proton conduction. The numerical calculation of frequency dependences of dielectric constant (ɛr’) were successfully explained by the superposition of Debye-type polarizations and electrolyte-electrode interfacial. [Copyright &y& Elsevier]

Ionic liquids have been recognized as ideal electrolytes for electrochemical systems owing to their unique properties such as non-volatility, non-flammability, high ionic conductivity, and gel-forming property with polymers. The examples include lithium batteries, fuel cells, double-layer capacitors, actuators, and dye-sensitized solar cells (DSSCs). Here, we revealed the details of charge transport in conventional ionic liquids, proton-conducting protic ionic liquids, and electron-transporting ionic liquids. The latter two examples were task-specific ionic liquids, potentially applicable as fuel cell electrolytes under non-humidifying conditions and also as non-volatile electrolytes in DSSCs, where charge transport occurs via the so-called Grotthuss-like mechanism. To realize polymer electrolytes with high ionic conductivity, we exploited the high ionic conductivity of ionic liquids. In situ free radical polymerization of compatible vinyl monomers in an ionic liquid afforded a novel series of polymer electrolytes, which we named ‘ion gels’. The ionic conductivity at ambient temperature reached a value close to 10-2 S cm-1. The number of carrier ions, calculated from the Nernst-Einstein equation, was found to increase in the ion gels from the corresponding value for the ionic liquid itself, which seems to be caused by the interaction between the polymer matrix and the ionic liquid. [ABSTRACT FROM AUTHOR]

The article presents abstracts of studies about polymers. The articles include Design of Polymer Electrolytes to Realize High Lithium-Ionic Conductivity With Fast Interfacial Charge Transfer, by Hiroyuki Tokuda, et al, Thermal and Liquid Crystalline Properties of Ionic Liquid Crystalline Systems, by Seiji Ujhe, et al, and Lithium Electrolyte Design on the Basis of Ion Dynamics Measurements and Analyses.