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The physical properties of an ABA triblock copolymer-based thermoplastic elastomer, containing a poly(lauryl methacrylate-co-methacrylic acid) midblock and poly(methyl methacrylate) endblocks, were enhanced through neutralization of the methacrylic acid (MAA) repeat units with NaOH to form ionic interactions in the midblock. Rheological properties of the midblock and mechanical properties of the triblock copolymer were investigated as functions of acid (MAA) and ion content. Midblock relaxation times (τ) increased with increasing acid and ion content, however the activation energy extracted from an Arrhenius analysis appeared constant for all acid and ion contents. Meanwhile, the factors of enhancement of the strain at break and tensile strength (as compared to the baseline polymer without ionic interactions or hydrogen bonding) collapsed onto master curves when plotted as functions of log τ, indicating the mechanical behavior of the triblock copolymer could be tuned through varying the relaxation time of the midblock. The tensile strength increased by as much as a factor of 17 times greater than that of the baseline polymer. More moderate enhancements were observed in the strain at break, with the maximum strain at break occurring at intermediate relaxation times. This suggests that midblock chain dynamics are a governing factor for the mechanical property enhancements, due to the effects of the ionic aggregates and chain mobility on stress dissipation under tensile deformation. 

By employing 3,5-bis(trifluoromethyl) pyrazole (TFMP) as an electrolyte additive in both aqueous and non-aqueous mediums, a versatile interphase strategy is achieved. This facilitates stable Zn anodes with improved efficiency and longer cycling life. 

Abstract Electroluminescence efficiencies and stabilities of quasi-two-dimensional halide perovskites are restricted by the formation of multiple-quantum-well structures with broad and uncontrollable phase distributions. Here, we report a ligand design strategy to substantially suppress diffusion-limited phase disproportionation, thereby enabling better phase control. We demonstrate that extending the π-conjugation length and increasing the cross-sectional area of the ligand enables perovskite thin films with dramatically suppressed ion transport, narrowed phase distributions, reduced defect densities, and enhanced radiative recombination efficiencies. Consequently, we achieved efficient and stable deep-red light-emitting diodes with a peak external quantum efficiency of 26.3% (average 22.9% among 70 devices and cross-checked) and a half-life of ~220 and 2.8 h under a constant current density of 0.1 and 12 mA/cm 2 , respectively. Our devices also exhibit wide wavelength tunability and improved spectral and phase stability compared with existing perovskite light-emitting diodes. These discoveries provide critical insights into the molecular design and crystallization kinetics of low-dimensional perovskite semiconductors for light-emitting devices. 

Abstract All-solid-state sodium batteries (ASSSBs) are promising candidates for grid-scale energy storage. However, there are no commercialized ASSSBs yet, in part due to the lack of a low-cost, simple-to-fabricate solid electrolyte (SE) with electrochemical stability towards Na metal. In this work, we report a family of oxysulfide glass SEs (Na 3 PS 4− x O x , where 0 <  x  ≤ 0.60) that not only exhibit the highest critical current density among all Na-ion conducting sulfide-based SEs, but also enable high-performance ambient-temperature sodium-sulfur batteries. By forming bridging oxygen units, the Na 3 PS 4− x O x SEs undergo pressure-induced sintering at room temperature, resulting in a fully homogeneous glass structure with robust mechanical properties. Furthermore, the self-passivating solid electrolyte interphase at the Na|SE interface is critical for interface stabilization and reversible Na plating and stripping. The new structural and compositional design strategies presented here provide a new paradigm in the development of safe, low-cost, energy-dense, and long-lifetime ASSSBs. 

Titanium dioxide (TiO 2 ) nanoparticles have been widely studied for water treatment applications; however, natural organic matter (NOM) is often reported to hamper the efficiency of the nanoparticles toward the degradation of target pollutants. Phosphate treatment has been proposed as a potentially facile solution to this problem, as phosphate competes for TiO 2 surface sites to diminish the NOM adsorption. However, the potential importance of the conditions of the NOM exposure and the residual NOM remaining after phosphate treatment have not been fully explored. Here, we investigate the reactivity of phosphate-treated TiO 2 nanoparticles with NOM coatings adsorbed from two background water chemistries, deionized water (TiO 2 –NOM DIW ) and moderately hard water (TiO 2 –NOM MHW ). Thorough characterization by size exclusion chromatography revealed that the adsorbed NOM was only partially displaced after phosphate treatment, with a higher adsorbed mass and wider variety of NOM species persisting on TiO 2 –NOM MHW compared to TiO 2 –NOM DIW . Although the remaining adsorbed NOM did not significantly influence the degradation rate of phenol as a model pollutant, remarkably distinct effects were observed in the degradation of catechol as an oxidative byproduct of phenol, with TiO 2 –NOM MHW hindering catechol degradation and TiO 2 –NOM DIW accelerating catechol degradation. The suppressed reactivity for TiO 2 –NOM MHW was attributed to hindrance of the physical adsorption of catechol to the TiO 2 surface by the NOM MHW layer as well as changes in the reactive oxygen species profile as measured by electron paramagnetic resonance (EPR) spectroscopy, whereas the enhanced reactivity for TiO 2 –NOM DIW was attributed to higher hole formation, suggesting participation of the NOM DIW layer in electron transfer processes. This research highlights the critical importance of the NOM surface coating in directing the mechanisms for pollutant degradation in photocatalytic nano-enabled water treatment applications. 

Covalently networked polymers offer desirable non-crystallinity and mechanical strength for solid polymer electrolytes (SPEs), but the chemically active cross-links involved in their construction could deteriorate the compatibility with high-energy cathode materials that are electrophilic and/or in the charged state. Herein we reveal a strong dependence of cyclability of such cathodes on the reactivity of covalently networked SPEs and demonstrate a polymer design that renders these SPEs chemically inert. We designed and synthesized two hybrid networks, both with polyethylene oxide as the cation conducting component and polyhedral oligomeric silsesquioxane as the branch point, but respectively use alkylamino and chemically inert triazole groups as cross-links. All-solid-state cells using the alkylamino-containing SPE underwent rapid degradation while cells using triazole SPEs showed stable cycling.