Separators play a pivotal role in the electrochemical performance and safety of lithium-ion batteries (LIBs). The commercial microporous polyolefin-based separators often suffer from inferior electrolyte wettability, low thermal stability, and severe safety concerns. Herein, a novel kind of highly flexible and porous separator based on hydroxyapatite nanowires (HAP NWs) with excellent thermal stability, fire resistance, and superior electrolyte wettability is reported. A hierarchical cross-linked network structure forms between HAP NWs and cellulose fibers (CFs) via hybridization, which endows the separator with high flexibility and robust mechanical strength. The high thermal stability of HAP NW networks enables the separator to preserve its structural integrity at temperatures as high as 700 °C, and the fire-resistant property of HAP NWs ensures high safety of the battery. In particular, benefiting from its unique composition and highly porous structure, the as-prepared HAP/CF separator exhibits near zero contact angle with the liquid electrolyte and high electrolyte uptake of 253%, indicating superior electrolyte wettability compared with the commercial polyolefin separator. The as-prepared HAP/CF separator has unique advantages of superior electrolyte wettability, mechanical robustness, high thermal stability, and fire resistance, thus, is promising as a new kind of separator for advanced LIBs with enhanced performance and high safety.

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The Pd-catalyzed asymmetric allylic alkylation (AAA) of phenol allyl carbonates serves as an efficient strategy to construct the allylic C-O bond allowing access to chiral chromans in up to 98% ee. The effect of pH and the influence of olefin geometry, as well as substitution pattern on the ee and the absolute configuration of the chiral chromans were explored in detail. These observations suggest a mechanism involving the cyclization of the more reactive pi-allyl palladium diastereomeric intermediate as the enantiodiscriminating step (Curtin-Hammett conditions). This methodology led to the enantioselective synthesis of the vitamin E core, the first enantioselective total synthesis of (+)-clusifoliol and (-)-siccanin, and the synthesis of an advanced intermediate toward (+)-rhododaurichromanic acid A.

Solubility behaviors of binary difluoromethane (HFC-32) and 1,1-difluoroethane (HFC-152a) systems with ionic liquids (ILs) 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim]OTf) and 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim]OTf) have been studied by using an isothermal synthetic apparatus at temperatures (273.15, 298.15, 323.15 and 348.15) K and at pressures (0.04 to 1.0) MPa. Experimental solubility data were successfully correlated with the nonrandom two-liquid (NRTL) activity coefficient model. It was found that the solubility of hydrofluorocarbons (HFCs) in ILs is affected by the change of alkyl chain length in the cation. ' MATERIAL AND METHODSMaterials. The hydrofluorocarbon HFC-32 (CH 2 F 2 , CAS registry no. 75-10-5) and HFC-152a (CH 3 ÀCHF 2 , CAS registry

Wallpaper with multiple functions, such as fire resistance and an automatic alarm in fire disasters, will be attractive for the interior decoration of houses. Herein, we report a smart fire alarm wallpaper prepared using fire-resistant inorganic paper based on ultralong hydroxyapatite nanowires (HNs) and graphene oxide (GO) thermosensitive sensors. At room temperature, the GO thermosensitive sensor is in a state of electrical insulation; however, it becomes electrically conductive at high temperatures. In a fire disaster, high temperature will rapidly remove the oxygen-containing groups of GO, leading to the transformation process of GO from an electrically insulated state into an electrically conductive one. In this way, the alarm lamp and alarm buzzer connected with the GO thermosensitive sensor will send out the alerts to people immediately for taking emergency actions. After the surface modification with polydopamine of GO (PGO), the sensitivity and flame retardancy of the GO thermosensitive sensor are further improved, resulting in a low responsive temperature (126.9 °C), fast response (2 s), and sustained working time in the flame (at least 5 min). Compared with combustible commercial wallpaper, the smart fire alarm wallpaper based on HNs and GO (or PGO) is superior owing to excellent nonflammability and high-temperature resistance of HNs, which can protect the GO (or PGO) thermosensitive sensor from the flames. The smart fire alarm wallpaper can be processed into various shapes, dyed with different colors, and printed with the commercial printer and thus has promising applications in high-safety interior decoration of houses.

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A comprehensive summary of phosphorus and metal/nonmetal phosphides and corresponding composites as anodes for sodium-ion batteries.