The lithium–sulfur battery is an attractive option for next‐generation energy storage owing to its much higher theoretical energy density than state‐of‐the‐art lithium‐ion batteries. However, the massive volume changes of the sulfur cathode and the uncontrollable deposition of Li2S2/Li2S significantly deteriorate cycling life and increase voltage polarization. To address these challenges, we develop an ϵ‐caprolactam/acetamide based eutectic‐solvent electrolyte, which can dissolve all lithium polysulfides and lithium sulfide (Li2S8–Li2S). With this new electrolyte, high specific capacity (1360 mAh g−1) and reasonable cycling stability are achieved. Moreover, in contrast to conventional ether electrolyte with a low flash point (ca. 2 °C), such low‐cost eutectic‐solvent‐based electrolyte is difficult to ignite, and thus can dramatically enhance battery safety. This research provides a new approach to improving lithium–sulfur batteries in aspects of both safety and performance.

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Advancing solution-based additive manufacturing of functional materials demands a fundamental understanding of how nanoparticles straddling a liquid-vapor interface influence evaporation. Using many-body dissipative particle dynamics, we model evaporation at liquidvapor interfaces with adsorbed nanoparticles. We quantitatively characterize the interfacial mechanics and the nanoparticle-mediated evaporation, using a particle-free interface as the reference system. We demonstrate that particle-particle interactions are critical for surface tension reduction induced by nanoparticles. The comparison of evaporation rates measured for different surface coverages with partially-wetted nanoparticles shows that the interface-bound nanoparticles can suppress evaporation through reducing the accessible interfacial area. We also observe reduced evaporation rates when the wettability of nanoparticles is varied from hydrophilic to hydrophobic while the surface coverage is kept approximately constant. This behavior suggests that obstruction in the evaporation path of escaping vapor beads can also inhibit net evaporation. The results also indicate the interfacial mechanics has no direct correlation with evaporation. Further analysis of the evaporation suppression provides important insight that the retardation effect of surfacecovering nanoparticles depends on ambient conditions and highlights that the nanoparticle monolayers modulate evaporation in a similar manner as insoluble surfactant monolayers.

Emulsion polymerization is a versatile approach to produce different polymeric nanoparticle morphologies, which can be useful in a variety of applications. However, the detailed mechanism of the morphology formation is not entirely clear. We study the kinetics of nanoparticle morphology evolution during a seeded emulsion polymerization using both experimental and computational tools. Lightly crosslinked polystyrene seeds were first synthesized using dispersion polymerization. Then the seed particles were swollen in tert-butyl acrylate and styrene monomers, and subsequently polymerized into nanoparticles of dumbbell and multilobe morphologies. It was discovered that both the seed and final particle morphology were affected by the methanol concentration during the seed synthesis.Systematically adjusting the methanol amount will not only yield spherical seed particles of different size, but also dumbbell particles even without the second monomer polymerization. In addition to methanol concentration, morphology can be controlled by crosslinking density. The kinetics studies revealed an