Self‐assembly of various metallo‐supramolecular coordination polyelectrolytes (MEPEs) based on pyridine ring functionalized ditopic bis‐terpyridines, as well as the electrochromic property is ...presented. MEPEs derived from electron‐donating OMe functionalized ligands exhibit rapid switching rates, good reversibility, high stability, and an optical memory. The first structure‐property relationships are proposed, which are needed for the de novo design and fabrication of new materials.
Since the initial report by Lehn et al. in 1979, ruthenium tris(bipyridine) (Ru(bpy)32+) and its numerous derivatives were applied as photosensitizers (PSs) in a large panel of photocatalytic ...conditions while the bis(terpyridine) analogues were disregarded because of their low quantum yields and short excited-state lifetimes. In this study, we prepared a new terpyridine ligand, 4′-(4-bromophenyl)-4,4‴:4″,4‴′-dipyridinyl- 2,2′:6′,2″-terpyridine (Bipytpy) and used it to prepare the heteroleptic complex Ru(Tolyltpy)(Bipytpy)(PF6)2 (1; Tolyltpy = 4′-tolyl-2,2′:6′,2′-terpyridine). Complex 1 exhibits enhanced photophysical properties with a higher quantum yield (7.4 × 10–4) and a longer excited-state lifetime (3.8 ns) compared to those of Ru(Tolyltpy)2(PF6)2 (3 × 10–5 and 0.74 ns, respectively). These enhanced photophysical characteristics and the potential for PS–catalyst interaction through the peripheral pyridines led us to apply the complex for visible-light-driven hydrogen evolution. The photocatalytic system based on 1 as the PS, triethanolamine as a sacrificial donor, and cobaloxime as a catalyst exhibits sustained activity over more than 10 days under blue-light irradiation (light-emitting diode centered at 450 nm). A maximum turnover number of 764 was obtained after 12 days.
Polymer brushes are grown on both hydrophobic and hydrophilic nanocrystals by surface‐initiated atom‐transfer radical polymerization. The poly{2‐(dimethylamino)ethyl methacrylate}‐coated nanocrystals ...are well dispersed in both water and most organic solvents without detectable aggregation and deterioration of their intrinsic properties. This methodology paves a simple and efficient way to direct nanocrystals into specific media.
Strata pack: Electroactive cytochrome c multilayer assemblies were constructed within a polyelectrolyte network on a gold electrode. Up to 15 layers were electroactive, with a linear increase in ...redoxactive protein per layer. Evidence for a protein–protein electron transfer through the assembly was found (pathway marked by arrows in the picture).
Based on the interfacial self-assembly of magnetite nanoparticles, we demonstrate the formation of colloidosomes with shells predominantly composed of monolayers of liquid-like, close-packed ...nanoparticles. The gelation of aqueous phase with agarose leads to robust and water-dispersible nanoparticle colloidosomes, allowing encapsulation of various water soluble materials. The cutoff of the nanoparticle colloidosomes obtained is primarily defined by the nanoparticle size. This controllable permeability should be of great importance for the encapsulation application.
Abstract
The construction of the ATLAS strip tracker barrel will require the assembly of 12,000 barrel detector modules over the course of 3.5 years. In 2022, during the module pre-production phase, ...modules were found to display clusters of noisy channels outside required specifications when tested at operating temperatures (-35°C), called “Cold Noise”. Extensive investigations into the cause and mechanism of Cold Noise interrupted pre-production and occupied most barrel module assembly sites. This contribution presents an overview of the year-long investigations into Cold Noise, the final identification of the underlying mechanism and necessary changes for the transition to production.
Anisotropic thin film materials of metallosupramolecular polyelectrolyte-amphiphile complexes (denoted PACs) with structures at several length scales were fabricated through a multistep self-assembly ...process. Metal ion-mediated self-assembly of the ditopic ligand 1,4-bis(2,2′:6′,2′ ′-terpyridine-4′-yl)benzene and electrostatic binding with the amphiphile dihexadecyl phosphate result in a PAC with tailored surface chemical properties, including solubility and surface activity. The PAC forms a stable monolayer at the air-water interface that is readily transferred and oriented on solid supports with the Langmuir-Blodgett technique. The presented strategy unifies colloid and metallosupramolecular chemistry and opens a versatile route to hierarchical materials with tailored structures and functions.
Ultrathin multilayer films of a novel molybdenum(VI) polyoxometalate cluster ((NH4)21H3Mo57V6(NO)6O183(H2O)18) (Mo57) and poly(allylamine hydrochloride) (PAH) have been prepared by the consecutive ...stepwise adsorption of Mo57 and PAH from dilute aqueous solution. The Mo57/PAH multilayer films have been characterized by optical spectroscopy and small-angle X-ray reflectivity (XR) methods. UV−vis measurements reveal regular film growth with each Mo57 adsorption. The average Mo57 surface density was found to be (1.4 ± 0.4) × 1013 clusters per cm2, corresponding to an average surface coverage of 56 ± 12%. XR experiments confirm uniform film growth, with the film thickness increasing with each Mo57 adsorption step. The average thickness for the Mo57/PAH layer pair was determined to be 0.8 ± 0.1 nm. The Mo57 density in the film can be readily controlled by varying the polyelectrolyte interlayer separation between each Mo57 layer, and the total film thickness can be controlled by altering the number of adsorption cycles.
Replacement of the charge‐balancing counter cations in the second coordination sphere of polyoxomolybdate 1 by cationic surfactants is a simple and facile method to fabricate surfactant‐encapsulated ...clusters (SECs) with a well‐defined supramolecular architecture. The resulting SEC is hydrophobic, can be spread at the air‐water interface and forms remarkably ordered thin films.
Arrays of microcavities sealed by a semipermeable ultrathin polyelectrolyte multilayer membrane (see Figure) are prepared using a novel method. The cavities can be loaded with high‐molecular‐weight ...species. If the entrapped molecules have stimuli‐responsive properties, such structures can be potentially used as sensor arrays to probe, e.g., solution properties, as demonstrated in model experiments.
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