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Acidic lyotropic liquid crystals (LLCs) have an advantage in constructing continuous proton conduction pathways owing to the well-defined structures, but the contribution of LLC to proton conductivity is hard to determine for the water-dependent nature of LLC. An aqueous 4-(1-ethyldecyl) benzenesulfonic acid solution, exhibiting a lamellar LLC phase at low hydration levels and becoming a micellar solution at high hydration levels, is employed to investigate structure-dependent proton conductivity. Electrochemical impedance spectrum (EIS) characterization reveals that the proton conductivity reaches a maximum of 173 mS cm−1 in the LLC phase. Owing to the self-assembling, the degree of dissociation of -SO3H tends to stabilize at 0.26 with increasing hydration levels. An integrated rate constant Ki is derived to evaluate the effect of self-assembly on proton conductivity, which reaches 1.90 × 107 mS cm5 mol−2 in the LLC but decreases to 1.23 × 107 mS cm5 mol−2 in the micellar solution. The single fuel cell fabricated from the LLC supported membrane exhibits a peak power density of 23.7 mW cm−2, confirming the enhanced proton conductivity under actual working conditions. The results quantitatively unveil the effect of aqueous self-assembly on proton conduction and offer a guide for achieving high conductivities in hydrated electrolytes with well-defined architectures. [ABSTRACT FROM AUTHOR]

Monitoring of nucleus geometry and growth into dual types of periodically ring-banded morphology in poly(nonamethylene terephthalate) (PNT), respectively, Type-1 and Type-2, are done with detailed analyses using polarized-light optical microscopy (POM) in-situ CCD recording; the periodic assembly morphologies are characterized using atomic-force microscopy (AFM) and scanning electron microscopy (SEM). Different annealing treatments (Tmax = 110, 120, 130 °C) are accomplished at a crystallization temperature of 85 °C; effects on the nucleus geometry, number (25–10%) and volume fractions (33–15%) of Type-2 among two types of banded PNT spherulites are expounded. Growth of a specific type of periodically banded PNT spherulite is initiated from either highly elongated sheaf-like or well-rounded nuclei, with the final grown lamellae being self-packed as multi-shell structures. Nucleation geometry and crystallization parameters collectively lead to development of multiple types of banded PNT spherulites of different relative fractions.

Monitoring of nucleus geometry and growth into dual types of periodically ring-banded morphology in poly(nonamethylene terephthalate) (PNT), respectively, Type-1 and Type-2, are done with detailed analyses using polarized-light optical microscopy (POM) in-situ CCD recording; the periodic assembly morphologies are characterized using atomic-force microscopy (AFM) and scanning electron microscopy (SEM). Different annealing treatments (Tmax = 110, 120, 130 °C) are accomplished at a crystallization temperature of 85 °C; effects on the nucleus geometry, number (25–10%) and volume fractions (33–15%) of Type-2 among two types of banded PNT spherulites are expounded. Growth of a specific type of periodically banded PNT spherulite is initiated from either highly elongated sheaf-like or well-rounded nuclei, with the final grown lamellae being self-packed as multi-shell structures. Nucleation geometry and crystallization parameters collectively lead to development of multiple types of banded PNT spherulites of different relative fractions. [ABSTRACT FROM AUTHOR]