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Challenges facing high‐voltage/high‐capacity cathodes, in addition to the longstanding problems pertinent to lithium (Li)‐metal anodes, should be addressed to develop high‐energy‐density Li‐metal batteries. This issue mostly stems from interfacial instability between electrodes and electrolytes. Conventional carbonate‐ or ether‐based liquid electrolytes suffer from not only volatility and flammability but also limited electrochemical stability window. Here, we report a nitrile electrolyte strategy based on concentrated nitrile electrolytes (CNEs) with co‐additives. The CNE consists of high‐concentration lithium bis(fluorosulfonyl)imide (LiFSI) in a solvent mixture of succinonitrile (SN)/acetonitrile (AN). The SN/AN solvent mixture is designed to ensure high oxidation stability along with thermal stability, which are prerequisites for high‐voltage Li‐metal cells. The CNE exhibits interfacial stability with Li metals due to the coordinated solvation structure. Lithium nitrate (LiNO3) and indium fluoride (InF3) are incorporated in the CNE as synergistic co‐additives to further stabilize solid‐electrolyte interphase (SEI) on Li metals. The resulting electrolyte (CNE + LiNO3/InF3) enables stable cycling performance in Li||LiNi0.8Co0.1Mn0.1 and 4.9 V‐class Li||LiNi0.5Mn1.5O4 cells. Notably, the Li||LiNi0.5Mn1.5O4 cell maintains its electrochemical activity at high temperature (100 °C) and even in flame without fire or explosion. [ABSTRACT FROM AUTHOR]

Research describes a versatile pyridinium salt photoelectrocyclization/aziridine ring cleavage sequence methodology for the synthesis of mannostatin analogues, (+)-4-epimannostatin and (+)-mannostatin A regioisomers.

The photochemistry of selected N-silylalkyl-substituted phthalimides and maleimides is examined to analyze the generality and preparative consequences of a solvent effect on excited-state reaction chemoselectivities and quantum efficiencies. This solvent effect is observed in the photochemistry of N-((trimethylsilyl)butyl)phthalimide 10 and in the photochemistry of the N-silylpropyl-maleimide. The results show the generality of the solvent effect and how it can be applied to improve the preparative utility of the photochemistry of N-(silylalkyl)phthalimides and N-(silylalkyl)maleimides.

The C to O silyl migration occurs in the photochemical reactions of N-trimethylsilylmethyl imides which form azomethine ylide and this pathway is essential for cyclic and acyclic, conjugated silylmethyl imides. The photolysis of N-(trimethylsilyl)methyl maleimide generates the tricyclic product. Azomethine ylide intermediates are formed in the reaction of N-trimethylsilylmethyl aroyl imides where the excited state C to O silyl migration occurs.

Abstract Background Neuroblastoma, a frequently occurring solid tumour in children, remains a therapeutic challenge as existing imaging tools are inadequate for proper and accurate diagnosis, resulting in treatment failures. Nanoparticles have recently been introduced to the field of cancer research and promise remarkable improvements in diagnostics, targeting and drug delivery. Among these nanoparticles, quantum dots (QDs) are highly appealing due to their manipulatable surfaces, yielding multifunctional QDs applicable in different biological models. The biocompatibility of these QDs, however, remains questionable. Results We show here that QD surface modifications with N-acetylcysteine (NAC) alter QD physical and biological properties. In human neuroblastoma (SH-SY5Y) cells, NAC modified QDs were internalized to a lesser extent and were less cytotoxic than unmodified QDs. Cytotoxicity was correlated with Fas upregulation on the surface of treated cells. Alongside the increased expression of Fas, QD treated cells had increased membrane lipid peroxidation, as measured by the fluorescent BODIPY-C11 dye. Moreover, peroxidized lipids were detected at the mitochondrial level, contributing to the impairment of mitochondrial functions as shown by the MTT reduction assay and imaged with confocal microscopy using the fluorescent JC-1 dye. Conclusion QD core and surface compositions, as well as QD stability, all influence nanoparticle internalization and the consequent cytotoxicity. Cadmium telluride QD-induced toxicity involves the upregulation of the Fas receptor and lipid peroxidation, leading to impaired neuroblastoma cell functions. Further improvements of nanoparticles and our understanding of the underlying mechanisms of QD-toxicity are critical for the development of new nanotherapeutics or diagnostics in nano-oncology.

Abstract: As a facile and scalable approach to the surface modification of high-voltage cathode materials for lithium-ion batteries, direct UV-assisted conformal coating of poly(tris(2-(acryloyloxy)ethyl) phosphate) (PTAEP) gel polymer electrolyte on as-formed LiNi1/3Co1/3Mn1/3O2 (NCM) cathode is presented. The smooth and continuous PTAEP coating layer with nanometer-thickness (∼20 nm) is successfully introduced on the NCM surface without impairing electronic/ionic conduction pathways preformed in the NCM cathode. Owing to this structural uniqueness, the PTAEP-coated NCM cathode significantly improves the high-voltage (4.6 V) cycling performance and mitigates the exothermic reaction between the delithiated NCM and liquid electrolyte. This demonstrates that the conformal PTAEP nanocoating layer proposed herein, which is completely different from conventional inorganic material-based coating layers, acts as a new ion-conductive protective film that effectively suppresses unwanted interfacial side reactions between the high-voltage cathode materials and liquid electrolyte. [Copyright &y& Elsevier]