Construction of Supramolecular Liquid-Crystalline Metallacycles for Holographic Storage of Colored Images

Visible-Light-Driven Rotation of Molecular Motors in Discrete Supramolecular Metallacycles

The organization of molecular motors in supramolecular assemblies to allow the amplification and transmission of motion and collective action is an important step toward future responsive systems. Metal-coordination-driven directional self-assembly into supramolecular metallacycles provides a powerful strategy to position several motor units in larger structures with well-defined geometries. Herein, we present a pyridyl-modified molecular motor ligand (MPY) which upon coordination with geometrically distinct di-Pt(II) acceptors assembles into discrete metallacycles of different sizes and shapes. This coordination leads to a red-shift of the absorption bands of molecular motors, making these motorized metallacycles responsive to visible light. Photochemical and thermal isomerization experiments demonstrated that the light-driven rotation of the motors in the metallacycles is similar to that in free MPY in solution. CD studies show that the helicity inversions associated with each isomerization step in the rotary cycle are preserved. To explore collective motion, the trimeric motor-containing metallacycle was aggregated with heparin through multiple electrostatic interactions, to construct a multi-component hierarchical system. SEM, TEM, and DLS measurements revealed that the photo- and thermal-responsive molecular motor units enabled selective manipulation of the secondary supramolecular aggregation process without dissociating the primary metallacycle structures. These visible-light-responsive metallacycles, with intrinsic multiple rotary motors, offer prospects for cooperative operations, dynamic hierarchical self-assembled systems, and adaptive materials.

A multi-responsive supramolecular heparin-based biohybrid metallogel constructed by controlled self-assembly based on metal–ligand, host–guest and electrostatic interactions

A new family of supramolecular heparin-based biohybrid metallogels with multiple stimuli-responsive behaviours was constructed through the controlled self-assembly based on three orthogonal interactions within a single system.

A supramolecular dual-donor artificial light-harvesting system with efficient visible light-harvesting capacity

A supramolecular dual-donor artificial light-harvesting system with efficient visible light-harvesting capacity was constructed through the hierarchical self-assembly approach.

Highly Luminescent Liquid Crystals in Aggregation Based on Platinum(II) Complexes

Luminescent liquid crystals (LLCs) attract considerable attention because of their broad applications in displays, chemosensors, and anti-counterfeiting. However, it remains challenging to achieve a high luminescence efficiency in LCs because of the common aggregation-caused quenching effect. Herein, we demonstrate a facile approach to designing LLCs with a high quantum yield up to 88% by deliberately tuning the aggregation behavior of platinum(II) complexes with alkoxy chains (C_nH_2n+1O-). LLCs in hexagonal columnar and rectangular columnar phases are achieved when n = 12 and 16, respectively, as revealed by one-dimensional wide-angle X-ray diffraction and small-angle X-ray scattering. These LLCs are able to not only exhibit strong emission at elevated temperatures but also show attractive reversible vapochromism upon alternative CH₂Cl₂ and EtOH fuming, which imparts added functions and promises technological utility.

Heterometallic {ZnEu}-metal-organic framework for efficient chemical fixation of CO2

Based on a ligand-directed synthetic strategy, the acidic solvothermal reaction of ZnO, Eu2O3, and 4,4',4''-(pyridine-2,4,6-triyl)tri(1,3-benzenedicarboxylic acid) (H6PTTBA) generated a targeted robust double-walled honeycomb material {[EuIIIZnII(HPTTBA)(H2O)]·4DMF·3H2O}n (simplified as NUC-9), which featured excellent characteristics such as dual tubular nanochannels, high porosity, specific surface area, abundant exposed active metal sites, etc. Although both types of nano-channels (I and II) alternately arranged in the lattice and shaped by six rows of [EuIIIZnII(CO2)6(H2O)] SBUs possessed an equal amount of exposed active metal sites, they could be differentiated according to the discrepant inner surface functionalized by free carboxyl oxygen atoms or coordinated aqueous molecules. Moreover, an activated sample of NUC-9 exhibited better catalytic performance than documented Zn- or Eu-based MOFs for the chemical transformation of various epoxides into the related carbonates under comparatively mild conditions of 1 atm CO2 flow and 70 °C, which should be ascribed to the unsaturated Zn2+ and Eu3+ ions acting as strong Lewis acid sites and free carboxyl oxygen atoms as basic sites synergistically polarizing and activating the substrates of epoxides and CO2 and consequently promoting the reaction. Furthermore, the water-resistant framework of NUC-9 could selectively and sensitively discriminate Fe3+ in aqueous solution according to the fluorescence quenching effect. In addition, it is worth mentioning that the successful self-assembly of NUC-9 provides an effective synthetic technique by employing the designed favorable organic ligand for achieving the targeted functional model of MOFs.

Coordination-driven self-assembly of discrete supramolecular double-metallacycles

This review comprehensively summarizes the recent advances in the coordination-driven self-assembly of discrete supramolecular double-metallacycles.

Architecture transition of supramolecular polymers through hierarchical self-assembly: from supramolecular polymers to fluorescent materials

A new supramolecular crosslinked polymer and a gel with excellent self-repairing capability were prepared by double host–guest interactions.