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Understanding structure/property correlations in self‐assembly is a key but challenging requirement for developing functional materials. Herein, we explore the importance of ligand geometry to fine‐tune photophysical properties (MMLCT vs. MLCT excited states) and self‐assembly pathways in metallosupramolecular polymerization. To this end, we have designed two hydrophobic Pt(II) complexes, 1 and 2, containing a π‐extended bidentate bipyridine ligand with different substitution pattern, resulting in different molecular geometries (linear vs. V‐shaped). Detailed comparative studies revealed significant differences for both complexes in terms of their photophysical properties and self‐assembly pathways in non‐polar media. The V‐shaped topology of 1 enables facile face‐to‐face molecular stacking with a certain curvature leading to luminescent spherical assemblies exhibiting MMLCT states and short Pt⋅⋅⋅Pt contacts via a single‐step cooperative pathway. On the other hand, the higher preorganized linear topology of complex 2 induces a two‐step competitive self‐assembly process leading to the formation of one‐dimensional supramolecular polymers with slipped packing and MLCT‐originated emission. Our findings broaden the monomer scope for supramolecular polymerization and provide design guidelines for the realization of luminescent supramolecular assemblies. [ABSTRACT FROM AUTHOR]

Electrical and electronic equipment (EEE) have revolutionized our lives, however, their associated waste (WEEE) presents a global challenge because at this time EEE relies heavily on metals that are not commonly found in the living environment (Biosphere), which find their way into the environment during both production/disposal of EEE/WEEE. The use of organic components in EEE is increasingly common, particularly with the growing interest in flexible electronics. Here we describe an approach to device design employing in silico toxicity screening to assess the toxicity of the components chosen for use in EEE that is exemplified using inorganic and organic components known in the literature for the production of prototype organic light‐emitting electrochemical cells. This approach could easily be employed to screen a variety of components for which datasets to produce safety data sheets (SDSs) don't yet exist because they have not been produced in large scale or in a regulatory environment which necessitates this. The approach has significant potential to improve high throughput screening of components for EEE that are "safe‐by‐design", potentially in combination with AI and ML approaches. [ABSTRACT FROM AUTHOR]

The composite hydrogel of a nanoscale metal–organic framework (NMOF) and nanoclay has emerged as a new soft‐material with advanced properties and applications. Herein, we report a facile synthesis of a hydrogel nanocomposite by charge‐assisted self‐assembly of Pd@ZIF‐8 nanoparticles with Laponite® nanoclay which coat the surface of Pd@ZIF‐8 nanoparticles. Such surface coating significantly enhanced the thermal stability of the ZIF‐8 compared to the pristine framework. Further, the Pd@ZIF‐8+LP hydrogel nanocomposite shows better size‐selective catalytic hydrogenation of olefins than Pd@ZIF‐8 nanoparticles based on selective diffusion of the substrate. [ABSTRACT FROM AUTHOR]

Besides their widespread use in coordination chemistry, 2,2'‐bipyridines are known for their ability to undergo cis–trans conformational changes in response to metal ions and acids, which has been primarily investigated at the molecular level. However, the exploitation of such conformational switching in self‐assembly has remained unexplored. In this work, the use of 2,2'‐bipyridines as acid‐responsive conformational switches to tune supramolecular polymerization processes has been demonstrated. To achieve this goal, we have designed a bipyridine‐based linear bolaamphiphile, 1, that forms ordered supramolecular polymers in aqueous media through cooperative aromatic and hydrophobic interactions. Interestingly, addition of acid (TFA) induces the monoprotonation of the 2,2'‐bipyridine moiety, leading to a switch in the molecular conformation from a linear (trans) to a V‐shaped (cis) state. This increase in molecular distortion along with electrostatic repulsions of the positively charged bipyridine‐H+ units attenuate the aggregation tendency and induce a transformation from long fibers to shorter thinner fibers. Our findings may contribute to opening up new directions in molecular switches and stimuli‐responsive supramolecular materials. [ABSTRACT FROM AUTHOR]

Recently, research attention has been directed towards the coordination driven synthesis of gels, including coordination polymer gels (CPGs) and metal–organic cage based gels, which have shown applications in diverse fields, including optoelectronics, catalysis, sensing, gas-storage, and self-healing. A wide variety of CPGs and metal–organic cage based gels have been reported, to date, by choosing the right combination of metal ions and rationally designed organic linkers. In this article, we focused on recent developments in CPGs and metal–organic cage based gels and their applications. [ABSTRACT FROM AUTHOR]

Bandgap engineering in donor–acceptor conjugated microporous polymers (CMPs) is a potential way to increase the solar‐energy harvesting towards photochemical water splitting. Here, the design and synthesis of a series of donor–acceptor CMPs [tetraphenylethylene (TPE) and 9‐fluorenone (F) as the donor and the acceptor, respectively], F0.1CMP, F0.5CMP, and F2.0CMP, are reported. These CMPs exhibited tunable bandgaps and photocatalytic hydrogen evolution from water. The donor–acceptor CMPs exhibited also intramolecular charge‐transfer (ICT) absorption in the visible region (λmax=480 nm) and their bandgap was finely tuned from 2.8 to 2.1 eV by increasing the 9‐fluorenone content. Interestingly, they also showed emissions in the 540–580 nm range assisted by the energy transfer from the other TPE segments (not involved in charge‐transfer interactions), as evidenced from fluorescence lifetime decay analysis. By increasing the 9‐fluorenone content the emission color of the polymer was also tuned from green to red. Photocatalytic activities of the donor–acceptor CMPs (F0.1CMP, F0.5CMP, and F2.0CMP) are greatly enhanced compared to the 9‐fluorenone free polymer (F0.0CMP), which is essentially due to improved visible‐light absorption and low bandgap of donor–acceptor CMPs. Among all the polymers F0.5CMP with an optimum bandgap (2.3 eV) showed the highest H2 evolution under visible‐light irradiation. Moreover, all polymers showed excellent dispersibility in organic solvents and easy coated on the solid substrates. Tuning the bandgap: A series of donor–acceptor conjugated microporous polymers with tunable bandgap, showing energy‐transfer‐assisted charge‐transfer emission, was exploited as efficient photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

We design a flexible, amphiphilic LMWG consisting of donor and acceptor π-chromophores which self-assembles into a hydrogel and an organogel with different nano-morphologies. Different mechanisms of self-assembly evolve charge transfer (CT) emission in the hydrogel and LMWG-based emission in the organogel. Moreover, the hydrogel-nanostructure with surface exposed amide groups is explored for catalyzing Knoevenagel condensation reaction. [ABSTRACT FROM AUTHOR]

In recent times, significant attention has been paid to the development of functional coordination polymer gels (CPGs) from rationally designed low molecular weight gelators (LMWGs) and metal ions. Coordination of metal ions to LMWGs provides an opportunity to emulate metal based redox, optical, electronic and magnetic properties in soft CPG materials. The metal–LMWG interactions allow controlled growth of CPGs with different nanostructures such as fibers, tubes, rings, ribbons and vesicles. Furthermore, the nanoscale periodicity of metal ions and LWMGs in CPGs is of paramount importance for different optoelectronic applications. The easy processability and dynamic nature of CPGs are explored for application in diverse fields, including drug-delivery, gas storage, optoelectronics, chemo-sensing, self-healing, etc. Also, by taking advantage of dynamic metal–ligand coordination bonds various stimuli-responsive multi-functional CPGs are developed. In this feature article, we cover important examples of newly developed CPGs, which show potential applications in different fields. [ABSTRACT FROM AUTHOR]

Rational design and synthesis of a new low molecular weight gelator (LMWG) having 9,10-diphenylanthracene core and terminal terpyridine is reported. TbIII and EuIII ion coordination to a LMWG results in green and pink emissive coordination polymer gels, respectively, with coiled nanofiber morphology. Further, control over stoichiometry of LMWG:TbIII:EuIII leads to yellow and white light emitting bimetallic gels. [ABSTRACT FROM AUTHOR]

The process of assembling astutely designed, well-defined metal-organic cube (MOC) into hydrogel by using a suitable molecular binder is a promising method for preparing processable functional soft materials. Here, we demonstrate charge-assisted H-bonding driven hydrogel formation from Ga3+-based anionic MOC ((Ga8(ImDC)12)12−) and molecular binders, like, ammonium ion (NH4+), N-(2-aminoethyl)-1,3-propanediamine, guanidine hydrochloride and β-alanine. The morphology of the resulting hydrogel depends upon the size, shape and geometry of the molecular binder. Hydrogel with NH4+ shows nanotubular morphology with negative surface charge and is used for gel-chromatographic separation of cationic species from anionic counterparts. Furthermore, a photo-responsive luminescent hydrogel is prepared using a cationic tetraphenylethene-based molecular binder (DATPE), which is employed as a light harvesting antenna for tuning emission colour including pure white light. This photo-responsive hydrogel is utilized for writing and preparing flexible light-emitting display. A possible route to producing processable soft materials is by assembling metal organic cubes into hydrogels. Here the authors show charge-assisted H-bond driven self-assembly of Ga3+-based anionic metal organic cubes and suitable molecular binders towards multi-functional hydrogels. [ABSTRACT FROM AUTHOR]