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The synthesis of alkynyl trifluoromethyl selenoethers from copper‐mediated aerobic decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with [Me4N][SeCF3] is reported. The reaction proceeded smoothly under mild conditions and enabled the facile conversion of both aryl and alkyl alkynyl carboxylic acids to the corresponding trifluoromethyl selenoethers in good yields, demonstrating that decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with the nucleophilic [Me4N][SeCF3] reagent is feasible at ambient temperature without irradiation. Advantages of the method include the use of bench‐stable and non‐volatile alkynyl carboxylic acids as starting materials, readily accessible SeCF3 reagent, excellent functional group tolerance, and the avoidance of harsh reaction conditions. This copper‐mediated reaction represents the first decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with a SeCF3 source. [ABSTRACT FROM AUTHOR]

The synthesis of alkynyl trifluoromethyl selenoethers from copper‐mediated aerobic decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with [Me4N][SeCF3] is reported. The reaction proceeded smoothly under mild conditions and enabled the facile conversion of both aryl and alkyl alkynyl carboxylic acids to the corresponding trifluoromethyl selenoethers in good yields, demonstrating that decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with the nucleophilic [Me4N][SeCF3] reagent is feasible at ambient temperature without irradiation. Advantages of the method include the use of bench‐stable and non‐volatile alkynyl carboxylic acids as starting materials, readily accessible SeCF3 reagent, excellent functional group tolerance, and the avoidance of harsh reaction conditions. This copper‐mediated reaction represents the first decarboxylative trifluoromethylselenolation of alkynyl carboxylic acids with a SeCF3 source. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are a promising energy storage technology due to their tempting high theoretical capacity and energy density. Nevertheless, the wastage of active materials that originates from the shuttling effect of polysulfides still hinders advancement of Li-S batteries. The effective design of cathode materials is extremely pivotal to solve this thorny problem. Herein, surface engineering in covalent organic polymers (COPs) has been performed to investigate the influence of pore wall polarity on the performance of COP-based cathodes used for Li-S batteries. With the assistance of experimental investigation and theoretical calculations, performance improvement by increasing pore surface polarity and a synergy effect of the polarized functionalities, along with nano-confinement effect of the COPs, are disclosed, to which the improved performance of Li-S batteries including outstanding Coulombic efficiency (99.0 %) and extremely low capacity decay (0.08 % over 425 cycles at 1.0 C) is attributed. This work not only enlightens the designable synthesis and applications of covalent polymers as polar sulfur hosts with high utilization of active materials, but also provides a feasible guide for the design of effective cathode materials for future advanced Li-S batteries., (© 2023 Wiley-VCH GmbH.)

The hexagonal rare earth ferrites h -RFeO 3 (R = rare earth element) have been recognized as promising candidates for a room-temperature multiferroic system, and the primary issue for these materials is how to get a stable hexagonal structure since the centrosymmetric orthorhombic structure is generally stable for most RFeO 3 at room-temperature, while the hexagonal phase is only stable under some strict conditions. In the present work, h -Lu 1- x In x FeO 3 ( x = 0-1) thin films were prepared on a Nb-SrTiO 3 (111) single-crystal substrate by a pulsed laser deposition (PLD) process, and the multiferroic characterization was performed at room temperature. With the combined effects of chemical pressure and epitaxial strain, the stable hexagonal structure was achieved in a wide composition range ( x = 0.5-0.7), and the results of XRD (X-ray diffraction) and SAED (selected area electron diffraction) indicate the super-cell match relations between the h -Lu 0.3 In 0.7 FeO 3 thin film and substrate. The saturated P - E hysteresis loop was obtained at room temperature with a remanent polarization of about 4.3 μC/cm 2 , and polarization switching was also confirmed by PFM measurement. Furthermore, a strong magnetoelectric coupling with a linear magnetoelectric coefficient of 1.9 V/cm Oe was determined, which was about three orders of magnitude larger than that of h -RFeO 3 ceramics. The present results indicate that the h -Lu 1- x In x FeO 3 thin films are expected to have great application potential for magnetoelectric memory and detection devices.