Search

Metal Organic Frameworks (MOFs) are organic‐inorganic hybrid materials with exceptionally customizable composition and properties. MOFs intrinsically possess open metal sites, tunable pore size/shape and an ultra‐large specific surface area, and have obtained significant attention over the past 30 years. Furthermore, through the integration of functional moieties such as, molecules, functional groups, noble metal clusters and nanocrystals or nanoparticles into MOFs, the resulting composites have greatly enriched the physical and chemical properties of pure MOFs, enabling their application in a wider range of fields. Triethylamine (TEA) as an organic base has consistently played a fundamental role in the development of MOFs. In this Concept, the versatility of triethylamine when involved in the synthesis of MOFs is discussed. Four sections are used to elaborate on the role of TEA including: (1) Single crystal synthesis; (2) Size and morphology control; (3) Counterion of MOFs; (4) MOFs composites synthesis. In the last part, we highlight the potential of TEA for further developments. [ABSTRACT FROM AUTHOR]

MoS2, a typical layered transition‐metal dichalcogenide, is promising as an electrode material in supercapacitors. However, its low electrical conductivity could lead to limited capacitance if applied in electrochemical devices. Herein, a new nanostructure composed of hollow carbon–MoS2–carbon was successfully synthesized through an l‐cysteine‐assisted hydrothermal method by using gibbsite as a template and polydopamine as a carbon precursor. After calcination and etching of the gibbsite template, uniform hollow platelets, which were made of a sandwich‐like assembly of partial graphitic carbon and two‐dimensional layered MoS2 flakes, were obtained. The platelets showed excellent dispersibility and stability in water, and good electrical conductivity due to carbon provided by the calcination of polydopamine coatings. The hollow nanoplate morphology of the material provided a high specific surface area of 543 m2 g−1, a total pore volume of 0.677 cm3 g−1, and fairly small mesopores (≈5.3 nm). The material was applied in a symmetric supercapacitor and exhibited a specific capacitance of 248 F g−1 (0.12 F cm−2) at a constant current density of 0.1 A g−1; thus suggesting that hollow carbon–MoS2–carbon nanoplates are promising candidate materials for supercapacitors. Made to stack: A new nanostructure composed of hollow carbon–MoS2–carbon was successfully synthesized through an l‐cysteine‐assisted hydrothermal method by using gibbsite as a template and polydopamine as a carbon precursor. Results show this is a promising electrode candidate for application in supercapacitors. [ABSTRACT FROM AUTHOR]

Anhydrous nanoscopic CuF2 is synthesized from alkoxides Cu(OR)2 (R=Me, tBu) by their reaction either in pure liquid HF at −70 °C, or under solvothermal conditions at 150 °C using excess HF and THF as solvent. Depending on the synthesis method, nanoparticles of sizes between 10 and 100 nm are obtained. The compound is highly hygroscopic and forms different hydrolysis products under moist air, namely CuF2⋅2 H2O, Cu2(OH)F3, and Cu(OH)F, of which only the latter is stable at room temperature. CuF2 exhibits an electrochemical plateau at a potential of ≈2.7 V when cycled versus Li in half cell Li‐ion batteries, which is attributed to a non‐reversible conversion mechanism. The cell capacity in the first cycle depends on the particle size, being 468 mAh g−1 for ≈8 nm crystallite diameter, and 353 mAh g−1 for ≈12 nm crystallite diameter, referred to CuF2. However, such a high capacity cannot be sustained for several cycles and the capacity rapidly fades out. The cell voltage decreases to ≈2.0 V for CuF2⋅2 H2O, Cu2(OH)F3, and Cu(OH)F. As all the compounds studied in this work show irreversible conversion reactions, it can be concluded that copper‐based fluorides are unsuitable for Li‐ion battery applications. [ABSTRACT FROM AUTHOR]