Here we report a highly scalable yet flexible triple-layer structured porous C/SiO2 membrane via a facile phase inversion method for advancing Li–sulfur battery technology. As a multifunctional current-collector-free cathode, the conductive dense layer of the C/SiO2 membrane offers hierarchical macropores as an ideal sulfur host to alleviate the volume expansion of sulfur species and facilitate ion/electrolyte transport for fast kinetics, as well as spongelike pores to enable high sulfur loading. The triple-layer structured membrane cathode enables the filling of most sulfur species in the macropores and additional loading of a thin sulfur slurry on the membrane surface, which facilitates ion/electrolyte transport with faster kinetics than the conventional S/C slurry-based cathode. Furthermore, density functional theory simulations and visual adsorption measurements confirm the critical role of the doped SiO2 nanoparticles (∼10 nm) in the asymmetric C membrane in suppressing the shuttle effect of polysulfides via chemisorption and electrocatalysis. The rationally designed C/SiO2 membrane cathodes demonstrate long-term cycling stability of 300 cycles at a high sulfur loading of 2.8 mg cm–2 with a sulfur content of ∼75%. This scalable yet flexible self-supporting cathode design presents a useful strategy for realizing practical applications of high-performance Li–S batteries.

the discharge capacity and cycle life. [2] Another weakness is the irreversible precipitation of Li 2 S 2 and Li 2 S on the cathode that leads to pore clogging and the loss of active materials, accompanied by severe polarization, large capacity degradation, and sluggish reaction kinetics. [3] Equally significant is that the dissolution of intermediate lithium polysulfides (LiPSs) induces inefficient self-discharge and the corrosion of the lithium metal anode. [4] In view of such a serious situation, tremendous efforts have been made to suppress polysulfide shuttling through physical confinement or chemical absorption mainly on the nanostructured carbon, [5] the rational structure design of carbonaceous materials with porous structures that efficiently provide the physical confinement of dissolved polysulfides, and a fast path for ion/electron transfer. [6] However, the nonpolar carbon cannot ensure strong adsorption of polar polysulfides. LiPSs detach from carbon hosts and diffuse into the electrolyte, resulting in capacity decay after several charge-discharge cycles. [7] In the meantime, it is also a large challenge for the oxidation of insoluble Li 2 S to sulfur during the charging process, which is important for achieving high reversible capacity and coulombic efficiency. However, the existence of overpotential in the charge process reveals that the oxidation of deposited short chain polysulfides needs a high activation energy, so it is crucial to reduce the activation energy of the reactions to promote the transformation of insulating short-chain LiPSs to long-chain LiPSs. [8] Hence, understanding and controlling the kinetics is the first step for remarkable improvement of battery performance. Reference to the fast reaction kinetics of the oxygen reduction reaction in fuel cells and the electrocatalysis concept of enhancing the redox reactions of polysulfides was developed by Arava et al., [9] who confirmed that Pt and Ni had an electrocatalysis effect on the reaction for LiPSs conversion. Subsequently, Pt nanoparticles loading on carbon spheres [10] and graphene sheets [11] also confirmed the efficacy of the Pt catalyst as well as the great adsorption strength for soluble LiPSs species. All the aforementioned reports involved inevitable catalyst outflow and heavy use of noble metal, which Reducing the deposit of discharge products and suppressing the polysulfide shuttle are critical to enhancing reaction kinetics in Li-S batteries. Herein, a Pt@Ni core-shell bimetallic catalyst with a patchlike or complete Ni shell based on a confined catalysis reaction in porous carbon spheres is reported. The Pt nanodots can effectively direct and catalyze in situ reduction of Ni 2+ ions to form core-shell catalysts with a seamless interface that facilitates the charge transfer between the two metals. Thus, the bimetallic catalysts offer a synergic effect on catalyzing reactions, which shows dual functions for catalytic oxidation of insoluble polysulfides to soluble polysulfides by effectively reducing the energy bar...

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Inonotus obliquus, a wild wood-decay fungus which grows on Betula trees in cool climates, has a variety of biological activities that the scientific community is paying more and more attention to. However, the research work is moving at a snail's pace. The methods of strain identification and the hypha microstructure have not been reported. We isolated one strain of filamentous molds from fruit body which was collected from birch wood on Changbai Mountain, cultivated mycelia on an inclined plane, and examined its micromorphology based on macroscopic examination. The strain was identified as I. obliquus by sequencing its ITS (internal transcribed spacer) domain. We subsequently investigated some of the mycelium polysaccharides' biological activities. The strain used in this study as the producers of antioxidation and anticancer polysaccharides was LNUF008. After fermentation in a 30-L fermenter, mycelia were obtained. The polysaccharides were extracted by transonic recirculation and ethanol precipitation. In order to identify the antioxidation effect, we designed an assay to test the inhibition of endogenous and Fe(2+)-Cys-induced lipid peroxidation as well as ferrous sulfate/ascorbate (Fe(2+)-VC)-induced mitochondrial swelling. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] method was used to study the antiproliferation activity of the polysaccharides on SMMC7721 hepatoma cells. The results indicate that I. obliquus polysaccharides exhibit high antitumor and antioxidation effects. The submerged culture method of growing I. obliquus will enable large-scale production of the polysaccharides.

Electrochemical reduction of CO2 into high value-added products is currently the effective strategy to mitigate global warming and energy storage conversion. Unfortunately, the lower selectivity, activity, and stability of electrocatalysts have been the biggest obstacle to further development. The Ni–N-doped ordered porous carbon material, which shows a unique structure and high surface area, has an excellent CO2 reduction reaction (CO2RR) activity and can also inhibit its competitive reaction-hydrogen evolution reaction (HER). Herein, we apply a simple dual-templating strategy to synthesize Ni–N-doped three-dimensional ordered macro-/mesoporous carbons (Ni–N-OMMCs) and investigate the CO2RR performance of Ni–N-OMMCs from precursors with different Ni amounts. The optimum catalyst (Ni–N-OMMC-0.6) exhibits excellent electrocatalytic activity with a maximum Faradaic efficiency of ∼98% for CO formation at −0.7 V vs the reversible hydrogen electrode (RHE) and shows a wide potential range from −0.65 to −1.0 V with a Faradaic efficiency of over 60%. In addition, after a 25 h stability test, the activity of the catalyst is only attenuated by 5.6%. This study demonstrates a promising strategy for preparing highly efficient catalysts for CO2RR.

With the rapid growth of material innovations, multishelled hollow nanostructures are of tremendous interest due to their unique structural features and attractive physicochemical properties. Continued effort has been made in the geometric manipulation, composition complexity, and construction diversity of this material, expanding its applications. Energy storage technology has benefited from the large surface area, short transport path, and excellent buffering ability of the nanostructures. In this work, the general synthesis of multishelled hollow structures, especially with architecture versatility, is summarized. A wealth of attractive properties is also discussed for a wide area of potential applications based on energy storage systems, including Li‐ion/Na‐ion batteries, supercapacitors, and Li–S batteries. Finally, the emerging challenges and outlook for multishelled hollow structures are mentioned.

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A scalable, three-layer-structured porous Fe3C/C membrane was developed for advancing the Li–S battery technology.