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The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur (Li/S) cells. A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue. Herein, we employed in situ/operando X-ray absorption spectroscopy (XAS) to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces, respectively, in a real-time condition. After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix (BSOC), we found the Li/S cell showed greatly improved sulfur utilization and longer life span. The operando S K-edge XAS results revealed that the BSOC modification was bi-functional: trapping polysulfides and catalyzing conversion of sulfur species simultaneously. We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection. Our results could offer potential stratagem for designing more advanced Li/S cells.

Rechargeable magnesium metal batteries need an electrolyte that forms a stable and ionically conductive solid electrolyte interphase (SEI) on the anodes. Here, we used molecular dynamic simulation, density functional theory calculation, and X‐ray photoelectron spectroscopy analysis to investigate the solvation structures and SEI compositions in electrolytes consisting of dual‐salts, magnesium bis(trifluoromethanesulfonyl)imide (MgTFSI2), and MgCl2, with different additives in 1,2‐dimethoxyethane (DME) solvent. We found that the formed [Mg3(μ‐Cl)4(DME)mTFSI2] (m = 3, 5) inner‐shell solvation clusters in MgTFSI2‐MgCl2/DME electrolyte could easily decompose and form a MgO‐ and MgF2‐rich SEI. Such electron‐rich inorganic species in the SEI, especially MgF2, turned out to be detrimental for Mg plating/stripping. To reduce the MgF2 and MgO contents in SEI, we introduce an electron‐deficient tri(2,2,2‐trifluoroethyl) borate (TFEB) additive in the electrolyte. Mg//Mg cells using the MgTFSI2‐MgCl2/DME‐TFEB electrolyte could cycle stably for over 400 h with a small polarization voltage of ~150 mV. Even with the presence of 800 ppm H2O, the electrolyte with TFEB additive could still preserve its good electrochemical performance. The optimized electrolyte also enabled stable cycling and high‐rate capability for Mg//Mo6S8 and Mg//CuS full cells, showing great potential for future applications. [ABSTRACT FROM AUTHOR]

Super‐hydrophobic surface has excellent waterproof, self‐cleaning and delayed icing properties, and is widely used in various fields, but its lack of durability restricts its large‐scale use. In this paper, carbon fiber composite material with excellent mechanical properties is selected as the substrate, PTFE nanoparticles with excellent hydrophobicity are used as the surface energy substance, and metal screen is selected as the template, combined with hot pressing molding process, a super‐hydrophobic surface with multi‐level micro‐nano structure is successfully constructed. The test shows that the water contact angle of the surface is 169°, and the rolling angle is about 2°. The contact angle of the surface is also over 150° for other liquids, and it bounces off the external water droplets for three times, so it can easily take away pollutants and keep the surface dry and clean under the action of water flow. In the same icing environment, compared with the original surface, it can prolong the freezing time of droplets by 5 times. After repeated rubbing, the surface still has superhydrophobic properties until the whole surface is completely destroyed. The preparation method used in this study is simple, and the prepared superhydrophobic surface has excellent performance, which is expected to promote the application of superhydrophobic surface in practical working conditions. Highlights: The preparation method is fast, efficient, low‐energy and environment‐friendly, and the used materials are simple and economical, and can be reused.The prepared surface has excellent hydrophobic performance for different media.The prepared superhydrophobic surface has low adhesion and droplet rebound performance.The prepared superhydrophobic surface has excellent delayed icing performance.The prepared superhydrophobic surface has excellent wear resistance. [ABSTRACT FROM AUTHOR]