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Chiral metal–organic frameworks (MOFs) have gained rising attention as ordered nanoporous materials for enantiomer separations, chiral catalysis, and sensing. Among those, chiral MOFs are generally obtained through complex synthetic routes by using a limited choice of reactive chiral organic precursors as the primary linkers or auxiliary ligands. Here, we report a template‐controlled synthesis of chiral MOFs from achiral precursors grown on chiral nematic cellulose‐derived nanostructured bio‐templates. We demonstrate that chiral MOFs, specifically, zeolitic imidazolate framework (ZIF),unc‐[Zn(2‐MeIm)₂, 2‐MeIm=2‐methylimidazole], can be grown from regular precursors within nanoporous organized chiral nematic nanocellulosesviadirected assembly on twisted bundles of cellulose nanocrystals. The template‐grown chiral ZIF possesses tetragonal crystal structure with chiral space group ofP4₁, which is different from traditional cubic crystal structure ofI‐43 mfor freely grown conventional ZIF‐8. The uniaxially compressed dimensions of the unit cell of templated ZIF and crystalline dimensions are signatures of this structure. We observe that the templated chiral ZIF can facilitate the enantiotropic sensing. It shows enantioselective recognition and chiral sensing abilities with a low limit of detection of 39 μM and the corresponding limit of chiral detection of 300 μM for representative chiral amino acid, D‐ and L‐ alanine.

Chiral metal–organic frameworks (MOFs) have gained rising attention as ordered nanoporous materials for enantiomer separations, chiral catalysis, and sensing. Among those, chiral MOFs are generally obtained through complex synthetic routes by using a limited choice of reactive chiral organic precursors as the primary linkers or auxiliary ligands. Here, we report a template‐controlled synthesis of chiral MOFs from achiral precursors grown on chiral nematic cellulose‐derived nanostructured bio‐templates. We demonstrate that chiral MOFs, specifically, zeolitic imidazolate framework (ZIF),unc‐[Zn(2‐MeIm)₂, 2‐MeIm=2‐methylimidazole], can be grown from regular precursors within nanoporous organized chiral nematic nanocellulosesviadirected assembly on twisted bundles of cellulose nanocrystals. The template‐grown chiral ZIF possesses tetragonal crystal structure with chiral space group ofP4₁, which is different from traditional cubic crystal structure ofI‐43 mfor freely grown conventional ZIF‐8. The uniaxially compressed dimensions of the unit cell of templated ZIF and crystalline dimensions are signatures of this structure. We observe that the templated chiral ZIF can facilitate the enantiotropic sensing. It shows enantioselective recognition and chiral sensing abilities with a low limit of detection of 39 μM and the corresponding limit of chiral detection of 300 μM for representative chiral amino acid, D‐ and L‐ alanine.

Here it is shown that Ti₃C₂T_xMXene flakes can be co‐assembled with recombinant silk fibroin in aqueous suspensions with silk fibroin nanolayers uniformly covering individual flakes. These bioencapsulated flakes evolve with time due to the gradual growth of silk bundles having β‐sheet secondary organization with unique nanofibrillar morphologies extending across flake edges and forming long fringes around individual MXene flakes. This spontaneous reorganization of recombinant silk suggests surface template‐initiated formation of intramolecular hydrogen bonding of silk backbones assisted by intermolecular electrostatic and hydrogen bonding with the MXene flake. The formation of dense and hydrophobic β‐sheets results in development of a protective shell that hinders the surface oxidation of Ti₃C₂T_xin colloidal solution in water and significantly extends the storage life of the individual MXene flakes. Moreover, assembly into organized laminated composites with individual bioencapsulated flakes tightly interconnected via biopolymer bundles and hairs produces robust freestanding electrically conductive membranes with enhanced transport properties.