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Hierarchical self‐assembly represents a powerful strategy for the fabrication of functional materials across various length scales. However, achieving precise formation of functional hierarchical assemblies remains a significant challenge and requires a profound understanding of molecular assembly interactions. In this study, we present a molecular‐level understanding of the hierarchical assembly of sequence‐defined peptoids into multidimensional functional materials, including twisted nanotube bundles serving as a highly efficient artificial light harvesting system. By employing synchrotron‐based powder X‐ray diffraction and analyzing single crystal structures of model compounds, we elucidated the molecular packing and mechanisms underlying the assembly of peptoids into multidimensional nanostructures. Our findings demonstrate that incorporating aromatic functional groups, such as tetraphenyl ethylene (TPE), at the termini of assembling peptoid sequences promotes the formation of twisted bundles of nanotubes and nanosheets, thus enabling the creation of a highly efficient artificial light harvesting system. This research exemplifies the potential of leveraging sequence‐defined synthetic polymers to translate microscopic molecular structures into macroscopic assemblies. It holds promise for the development of functional materials with precisely controlled hierarchical structures and designed functions. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 and other respiratory viruses spread via aerosols generated by infected people. Face masks can limit transmission. However, widespread use of disposable masks consumes tremendous resources and generates waste. Here, a novel material for treating blown polypropylene filtration media used in medical‐grade masks to impart antimicrobial activity is reported. To produce thin copper@ZIF‐8 core‐shell nanowires (Cu@ZIF‐8 NWs), Cu NWs are stabilized using a pluronic F‐127 block copolymer, followed by growth of ZIF‐8 to obtain uniform core‐shell structures. The Cu@ZIF‐8 NWs are applied to filtration media by dip coating. Aerosol filtration efficiency decreases upon exposure to ethanol (solvent for dip‐coating), but increases with addition of Cu@ZIF‐8 NWs. Cu@ZIF‐8 NWs shows enhanced antibacterial activity, compared to Cu NWs or ZIF‐8 alone, against Streptococcus mutans and Escherichia coli. Antiviral activity against SARS‐CoV‐2 is assayed using virus‐infected Vero E6 cells, demonstrating 55% inhibition of virus replication after 48 h by 1 µg of Cu@ZIF‐8 NWs per well. Cu@ZIF‐8 NWs' cytotoxicity is tested against four cell lines, and their effect on inflammatory response in A549 cells is examined, demonstrating good biocompatibility. This low‐cost, scalable synthesis and straightforward deposition of Cu@ZIF‐8 NWs onto filter media has great potential to reduce disease transmission, resource consumption, and environmental impact of waste. [ABSTRACT FROM AUTHOR]

High‐performance lightweight polymer fibers are attracting significant interest for wearable systems, where its thermal insulation performance is indispensable for harsh environments. However, one drawback of polymer fibers is its limited operating temperature range. Herein, a crosslinked poly(p‐phenylene terephthalamide) fiber and ceramic aerogel nanocomposite is reported, exhibiting hot and cold thermal management from cryogenic to high‐temperature condition (over 400 °C) and robust mechanical performance, which can be produced using additive textile manufacturing. The resulting ceramic aerogel nanocomposites demonstrate a low density (0.08 g cm−3), a low thermal conductivity (0.034 W m−1 K−1), and a high compressive mechanical strength of 1.1 MPa, due to the crosslinked interfacial interaction between the aramid fiber and the silica aerogel. A finite‐element model is developed to study the compression performance of aramid–aerogel composite, demonstrating that the robust mechanical performance is strengthened by interfacial bonding. These findings demonstrate that composite sheets are promising candidates for the low‐cost manufacturing of wearable textiles for applications in harsh environments. [ABSTRACT FROM AUTHOR]

This paper investigates the cyclic stress-strain behavior of steel-polypropylene-blended fiber-reinforced concrete (BFRC) under uniaxial cyclic compression. A total of 48 prism specimens were tested for different fiber volume fractions and aspect ratios. The results show that the introduction of blended fibers has synergetic effects on improving the cyclic behavior of concrete in terms of peak strength, postpeak ductility, hysteretic energy dissipation, and stiffness degradation. Moreover, the increase in the volume fractions of both steel and polypropylene fibers can lead to a remarkable decrease in plastic strain accumulation. Furthermore, the stiffness degradation ratio as well as the stress deterioration ratio of BFRC can be significantly alleviated in comparison with those of plain concrete, notwithstanding that the degradation amount is insensitive to the variations of fiber parameters. Subsequently, based on the test results, a constitutive model is developed to generalize the cyclic stress-strain responses of BFRC, with the contributions of blended fibers taken into account. The developed model is then verified by independent experimental results and other test data reported in the literature. It is observed that the prediction yields a close estimation of the cyclic compressive behavior of BFRC with varying fiber parameters. [ABSTRACT FROM AUTHOR]