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A convenient method was developed to prepare the diastereomer of dolutegravir tricyclic intermediate in the catalysis of EDCI/DMAP in up to 87% yield. Different solvents, temperature, and times were optimized. The synthesized diastereomer 6′ could be used as a standard for the industrial manufacture requirement of dolutegravir active pharmaceutical ingredient. [ABSTRACT FROM AUTHOR]

Because of its high theoretical specific capacity, lithium-sulfur batteries are regarded as one of the most promising secondary batteries. However, there are still a series of problems, which seriously affect the commercial application of lithium-sulfur batteries. Therefore, a magnetic porous carbon material was developed in this work for the modification of lithium-sulfur battery separators, which may reduce the shuttle effect of polysulfides and increase its electrochemical performances. The solvothermal preparation of Ni-Zn bimetallic MOF precursors was followed by a high-temperature carbonization in nitrogen environment to sublimate Zn ions and produce porous structures, achieving Ni@C(Zn) composite. In order to improve the electrochemical performances of lithium-sulfur batteries, the Ni@C(Zn) composite was coated on one side of the polyethylene (PE) separator. Ni@C(Zn) composite displays good physisorption and chemisorption properties, and it can also operate as a secondary current collector to promote the usage of active materials as well as inhibiting shuttle effect of polysulfides. By using Ni@C(Zn) coated PE separator, the initial discharge specific capacity of lithium sulfur battery is as high as 1278.6 mAh g−1 at a current density of 0.05 C when the S cathode is loaded with 3 mg cm−2 active materials. Furthermore, the discharge specific capacity in the first cycle at 0.5 C is 749.4 mAh g−1, which remains at 461 mAh g−1 after 500 long cycles, and the capacity retention rate is as high as 61.5%. Even when the S loading is as high as 5 mg cm−2, it can still experience a stable cycle of 100 cycles at 0.2 C. • Ni@C(Zn) composite was derived by bimetallic Ni-Zn MOFs. • Ni@C(Zn) composite was used as separator modification layer of lithium sulfur battery. • larger specific surface area and higher porosity can better block the shuttle of polysulfides. • Ni@C(Zn) composites have good catalytic effect which can promote the redox conversion of polysulfides. [ABSTRACT FROM AUTHOR]

• Ni-MOF derived Ni-C composites are used as separator coating layer of Li-S battery. • The influence of different morphology Ni-C composites are compared. • Ni nanodots are proved to have catalytic effect on the conversion of polysulfides. In order to solve the problems caused by the low conductivity of sulfur and the shuttle effect of polysulfides in lithium-sulfur battery (LSB), we conducted a series of studies and successfully prepared Ni-C composite materials employing Ni-MOF as the precursor, which were used as coating materials for the separator of LSB. Two kinds of ligands, terephthalic acid and trimesic acid were used to react with nickel nitrate to obtain Ni-MOF precursors and their carbonized products were named as Ni-C(B) and Ni-C(T) respectively. Ni-MOF precursors with different morphologies were obtained by different ligands, the precursor of Ni-C(B) is the petal-like layered microspheres and the morphology maintained after calcination, the precursor of Ni-C(T) has the structure of drug flake and agglomerates into a massive structure during the reaction. Because of the uniform distribution of nickel particles and the advantages in morphology and specific surface area, the performance of batteries equipped with Ni-C(B) modified separator is better than that of Ni-C(T) sample. Through a series of electrochemical performance tests, the results are consistent with our expectations. When the sulfur area density in positive electrode is 3 mg cm−2, the highest discharge capacity of the battery using Ni-C(B) coated separator is 1413.7 mAh g−1 at 0.05C, 1169.7 mAh g−1 at 0.1C and 997.3 mAh g−1 at 0.3C. Furthermore, the initial discharge capacity is 926 mAh g−1 at 0.5 C and can retain a capacity of 600 mAh g−1 after 300 cycles. [ABSTRACT FROM AUTHOR]

Abstract: A new bridge-building technique was used for facilitating H spillover on metal doped adsorbents for hydrogen storage at room temperature. By preadsorbing of CH4 on Pt/AX-21 (superactivated carbon), the adsorbed amount of hydrogen increased by ∼100% at 1 atm and 25 °C, attributed to the adsorbed CH4 serving as bridges for spillover. We conclude that the Benson–Boudart method can provide a good assessment for the dispersion of metals supported on Al2O3 (and zeolites). For carbon and SiO2 supports, even with pure H2, spillover leads to overestimates of dispersion, and any small amounts of gaseous impurities could lead to much greater overestimates. [Copyright &y& Elsevier]