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Lithium-sulfur batteries (LSBs) are promising candidates as next-generation secondary batteries due to their advantages with respect to cost and energy density. However, their practical application is hindered by their slow kinetics and the shuttle behavior of soluble polysulfide ions. Herein, we successfully prepared a three-dimensional porous conductive catalyst material with an atomic-level Ni–N 4 structure. The results showed that a strong adsorption of lithium polysulfides (LiPSs) by the Ni–N 4 catalytic active sites and a strong catalytic effect on the conversion of LiPSs in the sulfur reduction reaction (SRR) as well as the lithium sulfide oxidation reaction (SOR) were achieved, effectively inhibiting the shuttle effect of polysulfide ions and promoting the sulfur cathode kinetics process. Thus, the LSBs exhibited an excellent performance with a specific capacity of 829.8 mAh g–1 and an average coulombic efficiency of 98.8 % after 420 cycles at a high rate of 1 C. Our work provides new insights and novel efforts to solve the shuttle effect in LSBs. [ABSTRACT FROM AUTHOR]

Highly efficient synthesis of zeolites is an important goal given the many catalytic applications of zeolites in industrial chemical processes. The conventional zeolite syntheses, i.e., hydrothermal synthesis in a batch setup are usually challenged by certain limiting factors deriving from the long synthesis period or the low yield. Herein, we report that a combined strategy of organic promoter and zeolite seeding can remarkably improve the synthetic efficiency of high silica SSZ-13 zeolite. The low-cost promoter diethylamine (DEA) and zeolite seeds could both remarkably accelerate the crystallization rate of SSZ-13 zeolite, and DEA has a much higher beneficial effect on the solid yield as compared to the zeolite seeds. Consequently, the crystallization time could be unprecedentedly shorted by a factor of 30, instead of multiple days normally required. Besides, this novel protocol also exhibits high atom efficiency (93% of yield). The resultant high-silica nano-sized SSZ-13 zeolite shows good (hydro)thermal stability along with excellent catalytic performance for the MTO reaction. [Display omitted] • Synthetic efficiency of high-silica SSZ-13 zeolite was remarkably improved. • Cost-effective promoter and zeolite seeds were used in the synthesis gel. • Fast-synthesized SSZ-13 zeolite exhibits high crystallinity, high yield, small grain, and high stability. • Good performance in the MTO reaction; improved selectivity of light olefins. • Novel approach could be applied to the fast synthesis of other zeolite topologies. [ABSTRACT FROM AUTHOR]

DNA based synthetic molecular walkers are reminiscent of biological protein motors. They are powered by hybridization with fuel strands, environment induced conformational transitions, and covalent chemistry of oligonucleotides. Recent developments in experimental techniques enable direct observation of individual walkers with high temporal and spatial resolution. The functionalities of state-of-the-art DNA walker systems can thus be analyzed for various applications. Herein we review recent progress on DNA walker principles and characterization methods, and evaluate various aspects of their functions for future applications. [ABSTRACT FROM AUTHOR]