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The increasing demand for high-energy Li-ion batteries (LIBs) continues to push the development of electrode materials, particularly cathode materials, towards their capacity limits. Despite the enormous success, the stability and reliability of LIBs are becoming a serious concern due to the much-aggravated side reactions between electrode materials and organic electrolytes. How to stabilize the cathode/electrolyte interface is therefore an imperative and urgent task drawing considerable attention from both academia and industry. An active treatment on the surface of cathode materials, usually by introducing an inert protection layer, to diminish their side reaction with electrolytes turns out to be a reasonable and effective strategy. This Feature Article firstly outlines our synthesis efforts for the construction of a uniform surface nanocoating on various cathode materials. Different wet chemical routes have been designed to facilitate the control of growth kinetics of targeted coating species so that a precise surface coating could be achieved with nanometer accuracy. Furthermore, we showed the possibility to transform the outer coating layer into a surface doping effect through surface solid reaction at high temperature. A detailed discussion on the structure–performance relationship of these surface-controlled cathode materials is introduced to probe the stabilization mechanism. Finally, perspectives on the development tendency of high-energy cathodes for stable LIBs are provided. [ABSTRACT FROM AUTHOR]

A highly chemoselective platinum-catalyzed mono-lateral diboration of dialkynylsilanes for the construction of silicon-tethered alkynyl diborylalkenes is described, in which tris(4-methoxyphenyl)phosphine was found to be an effective ligand for the cis-addition of diboron agents to the silicon-tethered alkynes, and the chiral ligand (AFSi-Phos)-mediated diboration of dialkynylsilanes resulted in the desymmetric construction of silicon-stereogenic centers with promising enantioselectivity. [ABSTRACT FROM AUTHOR]

A host–guest inclusion compound, 18-crown-6 oxonium tetrachloride-gallium(III), was shown to undergo a 4/mmmFmm2-type ferroelectric phase transition with four crystallographically equivalent polarization directions at 337 K. To the best of our knowledge, this is the first host–guest inclusion compound shown to be a high-temperature multiaxial molecular ferroelectric. [ABSTRACT FROM AUTHOR]

The significant Tc enhancement of 110 K in [N-fluoromethyldabconium] triiodide lead caused by the promising design of H/F substitution is the first and unprecedented, opening up an applicable and universal strategy to effectively regulate the Tc working temperature in phase transition materials. [ABSTRACT FROM AUTHOR]

Two new organic ionic plastic crystals (OIPCs), [TMBM] [ClO4] (1) and [TMBM] [BF4] (2) (TMBM = trimethylbromomethyl ammonium), were successfully synthesized. Systematic characterization via differential scanning calorimetry (DSC), variable-temperature single-crystal X-ray diffraction, variable-temperature powder X-ray diffraction (PXRD) and dielectric measurements demonstrated that 1 and 2 undergo reversible high-temperature sequential phase transitions accompanied by distinct stepwise switchable dielectric anomalies (1 at 358 K and 388 K and 2 at 346 K and 379 K). The structural relatively ordered-disordered transitions of ClO4−, BF4− and [TMBM]+ contributed to the switching of the dielectric constant from the low-dielectric state to the high-dielectric state. Thus, OIPCs consisting of spherical ammonia cations and inorganic acid anions are proven to be promising in the search for high-temperature multi-step switchable dielectric materials. [ABSTRACT FROM AUTHOR]

Two new organic ionic plastic crystals (OIPCs), [TMBM] [ClO4] (1) and [TMBM] [BF4] (2) (TMBM = trimethylbromomethyl ammonium), were successfully synthesized. Systematic characterization via differential scanning calorimetry (DSC), variable-temperature single-crystal X-ray diffraction, variable-temperature powder X-ray diffraction (PXRD) and dielectric measurements demonstrated that 1 and 2 undergo reversible high-temperature sequential phase transitions accompanied by distinct stepwise switchable dielectric anomalies (1 at 358 K and 388 K and 2 at 346 K and 379 K). The structural relatively ordered-disordered transitions of ClO4−, BF4− and [TMBM]+ contributed to the switching of the dielectric constant from the low-dielectric state to the high-dielectric state. Thus, OIPCs consisting of spherical ammonia cations and inorganic acid anions are proven to be promising in the search for high-temperature multi-step switchable dielectric materials. [ABSTRACT FROM AUTHOR]

The significant Tc enhancement of 110 K in [N-fluoromethyldabconium] triiodide lead caused by the promising design of H/F substitution is the first and unprecedented, opening up an applicable and universal strategy to effectively regulate the Tc working temperature in phase transition materials.