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We report a three-dimensional (3D) molecular orientation control of a liquid crystal organic semiconductor (LC-OSC) based on the long-range ordering characteristic of an LC material. To this end, a synthetic LC-OSC molecule, MeOPh-BTBT-C8, with a fluidic nematic (N) phase that is essential for alignment control over a large area and a smectic E (SmE) phase showing high ordering, was prepared. A simple flipping of a sandwich cell made of the LC-OSC material between the top and bottom substrates that have uniaxial–planar degenerated alignment as well as crossed rubbing directions responds to the given surface anchoring condition and temperature gradient. Optical observation of the alignment-controlled LC-OSC was carried out by polarized optical microscopy (POM), and the corresponding charge carrier mobility was also measured by fabricating organic field-effect transistors (OFETs). Our platform offers a facile approach for multidirectional and multifunctional organic electronic devices using the stimulus–response characteristics of LC materials.

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.