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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]

[Display omitted] • The in-situ gel of SPE ensures interface compatibility and scalable preparation. • InPc was conducive to improving ionic conductivity and suppressing shuttle effect. • InPc induces a protective layer on the surface of the lithium. • The resulting pouch Li-S cell delivered an energy density of 325.5 Wh kg−1. Lithium-sulfur batteries (LSBs) are currently being investigated as a potential candidate for high-energy–density rechargeable batteries. However, the notorious shuttle effect and uncontrolled dendrite growth posed problems for the practical applications of LSBs. Here, a new solid polymer electrolyte (SPE) was developed by in-situ polymerization of 1,3-dioxolane (DOL) in the presence of a multifunctional indium phthalocyanine (PDOL@InPc). The InPc endows the SPE with improved ionic conductivity and merit inhibition of the shuttle effect, in addition to being an effective additive for inducing uniform Li deposition by reconstructing the electric field at the interface. The characteristics of ionic migration in PDOL@InPc were quantified, and agreement between experiment and simulation established a relationship between macroscopic characteristics and molecular-level processes. The interfacial side reaction was controlled by the PDOL@InPc electrolyte, which also improved the distribution of the Li+ flux for dense Li deposition. Li symmetrical batteries designed with PDOL@lnPc can withstand a current density of up to 0.5 mA cm−2 and cycle reliably for 1500 h. The PDOL@InPc electrolyte displayed a high ionic conductivity at room temperature of 3.7 mS cm−1 and a significant Li+ transference number of 0.63. The resulting Li-S battery (Li|PDOL@lnPc|Sulfur) delivered a significant 325.5 Wh kg−1 of energy density at 0.2 C (1 C = 1000 mA g−1) at the level of the multilayer-pouch cell under an extremely low electrolyte of 3.5 g g−1 Sulfur and high loading of 8.0 mg cm−2. This work provides a feasible strategy for the widespread implementation of LSBs with increased safety and a longer lifetime. [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]