Dynamic Entwined Topology in Helical Covalent Polymers Dictated by Competing Supramolecular Interactions

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(20)

Published: March 6, 2024

Abstract Naturally occurring polymeric structures often consist of 1D polymer chains intricately folded and entwined through non‐covalent bonds, adopting precise topologies crucial for their functionality. The exploration crystalline polymers dynamic covalent chemistry (DCvC) supramolecular interactions represents a novel approach developing polymers. This study shows that sub‐angstrom differences in the counter‐ion size can lead to various helical (HCP) topologies, including metal‐coordination HCP (m‐HCP) motif. Single‐crystal X‐ray diffraction (SCXRD) analysis HCP−Na revealed double pairs are formed by sodium ions coordinating spiroborate linkages form rectangular pores. helices interpenetrated unreacted diols ions. reticulation m‐HCP structure was demonstrated successful synthesis HCP−K. Finally, ion‐exchange studies were conducted show interconversion between structures. research illustrates how seemingly simple modifications, such as changes size, significantly influence topology determine which dominate crystal lattice.

Language: Английский

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Construction of single-crystal 3D covalent organic framework with three crossing sets of 2D sheets entanglement

Chem, Journal Year: 2024, Volume and Issue: 10(7), P. 2170 - 2179

Published: April 9, 2024

Language: Английский

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Isomeric covalent organic frameworks: opportunities and challenges

Trends in Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 1, 2025

Language: Английский

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Regulating the Isomerization Geometry and Energy State of Covalent Organic Frameworks for Enhanced Oxygen Reduction Activity

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 19, 2025

Abstract Embedding isomer entities onto crystalline frameworks with precisely defined spatial distributions represents a promising approach to enhancing the efficiency of oxygen reduction reaction (ORR) in fuel cells. However, accurately constructing covalent organic (COFs) regulate energy state effectively remains significant challenge. Herein, an innovative geometric isomerization strategy aimed at minimizing rotational barrier (ΔE), average local ionization (ALIE), and Gibbs free (ΔG) for ORR within COFs is proposed. Based on this strategy, isomeric Py‐COF‐αα 2,2‐substitution, Py‐COF‐ββ 3,3‐substitution, Py‐COF‐αβ 2,3‐substitution mainchain have been obtained. The electronic states intermediate adsorption capabilities are finely tuned through modification, yielding controllable chemical activity. Notably, lower ΔE between thiophenes achieves remarkable performance, evidenced by half‐wave potential 0.77 V vs reversible hydrogen electrode (RHE), surpassing most reported metal‐free electrocatalysts. Combined theoretical prediction situ Raman spectra, it revealed that increased dipole moment non‐uniform charge distribution caused endows pentacyclic‐carbon (thiophene β‐position) far from sulfur atoms efficient catalytic This work has opened up novel paradigm underscores pivotal role regulation facilitating catalysis.

Language: Английский

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3D interpenetrated covalent organic frameworks

Coordination Chemistry Reviews, Journal Year: 2025, Volume and Issue: 535, P. 216614 - 216614

Published: March 18, 2025

Language: Английский

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Regulating Electron Distribution in Regioisomeric Covalent Organic Frameworks for Efficient Solar‐Driven Hydrogen Peroxide Production

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

Abstract Covalent organic frameworks (COFs) are emerging as a transformative platform for photocatalytic hydrogen peroxide (H 2 O ) production due to their highly ordered structures, intrinsic porosity, and molecular tunability. Despite potential, the inefficient utilization of photogenerated charge carriers in COFs significantly restrains efficiency. This study presents two regioisomeric COFs, α ‐TT‐TDAN COF β COF, both incorporating thieno[3,2‐b]thiophene moieties, investigate influence regioisomerism on excited electron distribution its impact performance. The demonstrates remarkable solar‐to‐chemical conversion efficiency 1.35%, outperforming ‐isomeric counterpart, which is merely 0.44%. Comprehensive spectroscopic computational investigations reveal critical role subtle substitution change electronic properties. structural adjustment intricately connects structure dynamics, enabling precise regulation distribution, efficient separation transport, localization electrons at active sites. Moreover, this finely tuned interplay enhances oxygen reduction reaction. These findings establish new paradigm design, offering molecular‐level strategy advance reticular materials toward energy conversion.

Language: Английский

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Reactive regeneration in novel hybrid solvent: Achieving dual objectives of H2S conversion and absorbent regeneration

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 490, P. 151622 - 151622

Published: April 24, 2024

Language: Английский

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Single-Crystal Dynamic Covalent Organic Frameworks for Adaptive Guest Alignments

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 30, 2024

Dynamic 3D covalent organic frameworks (COFs) have shown a concerted structural transformation upon adaptive guest inclusion. However, the origin of conformational mobility and host–guest adaptivity remain conjecture pedal motions revolving imine linkages, often without considering steric hindrance from interwoven frameworks. Here, we present atomic-level observation rotational translational dynamics in single-crystal COF-300 inclusion various molecules, featuring multiple rotamers linkages switchable interframework noncovalent interactions. Specifically, developed diffusion gradient transimination protocol to facilitate growth COF single crystals, enabling high-resolution X-ray diffraction analysis. We uncovered metastable low-symmetry intermediate phases contracted expanded during evolution. identified torsion angles terephthalaldehyde diimine motifs that switch anti-periplanar syn-periplanar/anticlinal conformations. Moreover, linkage were concurrent with tetraphenylmethane units, which tend form quadruple phenyl embrace. Such allows adapt such as alcohols, esters, phenols, diols, double linear, herringbone, zigzag chains, triple helix, tubular alignments. Quantitative energy analyses revealed dynamic structure transformations are not arbitrary but follow specific pathways resemble protein folding. The work is paving way developing robust, dynamic, crystalline molecular sponges for studying condensed liquids need further crystallization.

Language: Английский

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Optimizing Propylene/Propane Sieving Separation through Gate‐Pressure Control within a Flexible Organic Framework

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 14, 2024

Abstract The separation of propylene (C 3 H 6 ) and propane 8 is great significance in the chemical industry, which poses a challenge due to their almost identical kinetic diameters similar physical properties. In this work, we synthesized an ultramicroporous flexible hydrogen‐bonded organic framework (named HOF‐FJU‐106) by using molecule 2,3,6,7‐tetra (4‐cyanophenyl) tetrathiafulvalene (TTF‐4CN). formation dimer causes TTF‐4CN molecular bend weaken π‐stacked interactions, coupled with flexibility C≡N H−C hydrogen bonds, leads reversible conversion between open closed frameworks through mutual slip adjacent layers/columns under activation stimulation gas molecules. Through adsorption isotherms enthalpy, HOF‐FJU‐106a exhibited adaptive stronger binding affinity for C 6, presented recorded uptake ratio /C (23.77) among presentative HOF materials at room temperature date. Importantly, shows interesting phenomenon about gate pressure control variable temperature, realized performance enhancement binary mixtures. This strategy designing HOFs thermoregulatory gating effect powerful way maximize materials.

Language: Английский

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Optimizing Propylene/Propane Sieving Separation through Gate‐Pressure Control within a Flexible Organic Framework

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 14, 2024

Abstract The separation of propylene (C 3 H 6 ) and propane 8 is great significance in the chemical industry, which poses a challenge due to their almost identical kinetic diameters similar physical properties. In this work, we synthesized an ultramicroporous flexible hydrogen‐bonded organic framework (named HOF‐FJU‐106) by using molecule 2,3,6,7‐tetra (4‐cyanophenyl) tetrathiafulvalene (TTF‐4CN). formation dimer causes TTF‐4CN molecular bend weaken π‐stacked interactions, coupled with flexibility C≡N H−C hydrogen bonds, leads reversible conversion between open closed frameworks through mutual slip adjacent layers/columns under activation stimulation gas molecules. Through adsorption isotherms enthalpy, HOF‐FJU‐106a exhibited adaptive stronger binding affinity for C 6, presented recorded uptake ratio /C (23.77) among presentative HOF materials at room temperature date. Importantly, shows interesting phenomenon about gate pressure control variable temperature, realized performance enhancement binary mixtures. This strategy designing HOFs thermoregulatory gating effect powerful way maximize materials.

Language: Английский

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