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The article focuses on construction of solid-liquid fluorine transport channel to enable highly reversible conversion cathodes. Topics include the conversion-type iron fluoride is a promising alternative cathode to intercalation oxides because of its higher energy density, and the intrinsic solid-solid conversion is sluggish during repeated splitting and rebonding of metal-fluorine moieties.

While a multitude of opinion mining studies have examined the impact of attribute performance on customer satisfaction, they have offered limited insights into the role performance of service employees by investigating tourists' experiences. Focusing on the hotel industry, this study investigated tourists' evaluations of service personnel by scrutinizing 68,439 hotel reviews and explored the asymmetric effects of employee performance on customer satisfaction according to service employee functions and traveler types. The results indicate that different travelers have distinct expectations of different kinds of services, thereby moderating the asymmetric impact of role performance on tourist satisfaction. Manager employee, in particular, constitutes an excitement factor for family, solo, and couple travelers. The findings have implications for the formulation of operation strategies to promote tourists' satisfaction rather than frustration. This study contributes to the literature by offering a novel understanding of the asymmetric effect of customer-personnel interactions on tourist satisfaction. [ABSTRACT FROM AUTHOR]

Conversion chemistry involving LiF splitting is an appealing route toward high capacity cathodes for Li-ion batteries. In general, cathodes based on LiF splitting need a redox host to provide the driving force for LiF decomposition from the surface. However, most of the systems are still far from practical owing to their limitations, especially the high charge voltage (4.5-5.0 V) needed to fully utilize the capacity and the subsequent low energy efficiency (<80%). The redox host is apparently the key to further reduce the required charge voltage and improve the energy efficiency. Here, a new LiF-NiFe2O4 conversion cathode chemistry is designed and demonstrated with a crystalline spinel oxide redox host. It is demonstrated that the new host effectively improves the surface redox and LiF splitting kinetics, which enable the new cathode to work at much lower charge cutoff voltage (4.2 V) without compromising the delivered capacity and voltage. The LiF-NiFe2O4 composite thin film is able to be discharged with large capacity of 237 mA h g-1 with high energy efficiency (88%), substantial pseudocapacitance contribution (>90%), and satisfactory capacity retention. This result indicates LiF splitting chemistry can become practical by carefully tailoring the redox host chemistry and optimizing the composition. [ABSTRACT FROM AUTHOR]

ZIF-67 (Co(MeIM)2, MeIM = 2-methylimidazole) was selected as a precursor to synthesize the metallic cobalt/carbon composites on Ni foam directly and intimately. The results show that ZIF-67 forms a uniform membrane and densely covers the Ni foam substrate. Besides, the cobalt/carbon composites obtained are composed of cobalt nanoparticles with a diameter up to around 2.6 nm, which are anchored on carbon homogeneously. The specific capacitance of the composites material is up to 512 F g−1 at a current density of 1 A g−1 in 1.0 M KOH electrolyte. Furthermore, the specific capacitance loss is ~46.4% with increase at the current density from 1 to 20 A g−1. More significantly, the specific capacitance retention rate is 87.5% at a current density of 5 A g−1 after 1000 cycles. These results suggest that the electrochemical performance can be greatly enhanced by the well-controlled size and distribution of the cobalt nanoparticles, which is mainly attributed to the unique structure and composition of ZIF-67. [ABSTRACT FROM AUTHOR]