Programming the hierarchical self-assembly of small molecules has been a fundamental topic of great significance in biological systems and artificial supramolecular systems. Precise and highly programmed self-assembly can produce supramolecular architectures with distinct structural features. However, it still remains a challenge how to precisely control the self-assembly pathway in a desirable way by introducing abundant structural information into a limited molecular backbone. Here we disclose a strategy that directs the hierarchical self-assembly of sodium thioctate, a small molecule of biological origin, into a highly ordered supramolecular layered network. By combining the unique dynamic covalent ring-opening-polymerization of sodium thioctate and an evaporation-induced interfacial confinement effect, we precisely direct the dynamic supramolecular self-assembly of this simple small molecule in a scheduled hierarchical pathway, resulting in a layered structure with long-range order at both macroscopic and molecular scales, which is revealed by small-angle and wide-angle X-ray scattering technologies. The resulting supramolecular layers are found to be able to bind water molecules as structural water, which works as an interlayer lubricant to modulate the material properties, such as mechanical performance, self-healing capability, and actuating function. Analogous to many reversibly self-assembled biological systems, the highly dynamic polymeric network can be degraded into monomers and reformed by a water-mediated route, exhibiting full recyclability in a facile, mild, and environmentally friendly way. This approach for assembling commercial small molecules into structurally complex materials paves the way for low-cost functional supramolecular materials based on synthetically simple procedures.

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Metal−organic frameworks (MOFs) are a promising class of functional materials with applications in catalysis, separations, electronics, and drug delivery, among others. Despite a range of techniques utilized for MOF synthesis, a generalizable and scalable approach has yet to be developed for producing MOFs without using environmentally damaging organic solvents. Here, we look at MOF synthesis as a reaction in an aqueous medium and propose new methods of measuring conversion and selectivity. We show that controlling reactant speciation via pH is a generalizable approach to producing the prototypical MOFs UiO-66, UiO-66-NH 2 , ZIF-L, and HKUST-1 with space−time yields (STY) of over 2250 kg m −3 day −1 , which is a 1 order of magnitude improvement for zirconium-based MOFs. We show that UiO-66-NH 2 crystallization is complete in 5 min at room temperature, with 70% of the extent of reaction completed by 30 s. Finally, we apply the rapid synthesis approach to coating cotton fabric with up to 20 wt % UiO-66-NH 2 using a sequential dip-coating (SQD) technique and demonstrate particulate matter (PM 1−4 ) filtration up to 85%. This work shows a greenchemistry-based, generalizable pathway to rapid synthesis for multiple MOFs and demonstrates its utility for filtration applications. The ability to produce alternative filtration materials is especially relevant under pandemic conditions, where SQD offers a rapid and high-throughput manner of providing air filtration by modifying commonly available textile materials.

A model was proposed to account for a new kind of history effect in the transport measurement of a sample with inhomogeneous flux pinning coupled with flux creep. The inhomogeneity of flux pinning was described in terms of alternating weak pinning (lower j c ) and strong pinning region (higher j c ). The flux creep was characterized by logarithmic barrier. Based on this model, we numerically observed the same clockwise V-I loops as reported in references.Moreover, we predicted behaviors of the V-I loop at different sweeping rates of applied current dI/dt and magnetic fields B a , etc. Electric transport measurement was performed in Ag-sheathed Bi 2−x Pb x Sr 2 Ca 2 Cu 3 O y tapes immersed in liquid nitrogen with and without magnetic fields. V-I loop at certain dI/dt and B a was observed. It is found that the area of the loop is more sensitive to dI/dt than to B a , which is in agreement well with our numerical results.

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