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With [5,10,15,20-tetra(4-carboxyphenyl)porphyrin]Mn(III) and sterically controlled 2,2¢-dimethyl-4,4¢-pyridine as the main raw materials, metal-organic framework thin films containingmetalloporphyrin (MnPor-MOF) with catalytically active sites were built up on functionalized quartz glass surfaces using a layer-by-layer self-assembly method. Retaining active catalytic sites and having a porous reticular structure, the MnPor-MOF films possessed remarkable photocatalytic activity for oxidative degradation of methylene blue in the presence of hydrogen peroxide under visible-light irradiation. Most meaningfully, the MnPor-MOF films were highly stable and simply and conveniently reusable, and are thus a potentially new organic material for photocatalytic wastewater treatment. [ABSTRACT FROM AUTHOR]

Fabricating structural complex assemblies from simple amino acid-based derivatives is attracting great research interests due to their easy accessibility and preparation. However, the morphological regulation of racemates (an equimolar mixture of enantiomers) were largely overlooked. In this work, through rational modulation of kinetic and thermodynamic parameters, we achieved multiple dimensional architectures employing tryptophan-based racemate (RPWM). Upon assembling, 1D bundled nanofibers, 2D lamellar nanostructure and 3D urchin-like microflowers could be obtained depending on the solvents used. The corresponding morphology evolutions were successfully illustrated by changing the enantiomeric excess (ee) value. Moreover, for RPWM, uniform 0D nanospheres were formed in H 2 O under 4 °C, which could spontaneously convert into lamella under ambient temperature. Taking advantages of its temperature-responsive phase change behavior, RPWM assemblies exhibited excellent removal efficiency for organic dye RhB, and could be reused for several consecutive cycles without significant changes in its removal performance. Taken together, it's rational to envision that the engineering of racemates assembly pathways can greatly increase the robustness in a wide variety of supramolecular materials and further lead to their blooming versatile applications., (© 2021 Wiley-VCH GmbH.)

Although chiral nanostructures have been fabricated at various structural levels, the transfer and amplification of chirality from molecules to supramolecular self-assemblies are still puzzling, especially for heterochiral molecules. Herein, four series of C 2 -symmetrical dipeptide-based derivatives bearing various amino acid sequences and different chiralities are designed and synthesized. The transcription and amplification of molecular chirality to supramolecular assemblies are achieved. The results show that supramolecular chirality is only determined by the amino acid adjacent to the benzene core, irrespective of the absolute configuration of the C-terminal amino acid. In addition, molecular chirality also has a significant influence on the gelation behavior. For the diphenylalanine-based gelators, the homochiral gelators can be gelled through a conventional heating-cooling process, whereas heterochiral gelators form translucent stable gels under sonication. The racemic gels possess higher mechanical properties than those of the pure enantiomers. All of these results contribute to an increasing knowledge over control of the generation of specific chiral supramolecular structures and the development of new optimized strategies to achieve functional supramolecular organogels through heterochiral and racemic systems., (© 2020 Wiley-VCH GmbH.)