Dispersing an ionic transition metal complex into an elastomeric matrix enables the fabrication of intrinsically stretchable light-emitting devices that possess large emission areas (∼175 mm(2)) and tolerate linear strains up to 27% and repetitive cycles of 15% strain. This work demonstrates the suitability of this approach to new applications in conformable lighting that require uniform, diffuse light emission over large areas.

The formation of polyrotaxanes by metal±ligand self-assembly is a viable method for the programmed organization of mechanically linked molecular components into a repeating framework. This has significant potential for producing materials that contain functional molecular entities that may be addressable or controllable. [1] The challenges of designing, synthesizing, and crystallizing such materials are many and manipulation easily aligns a single tube in an arbitrary direction. For demonstration we have further written the word ™tube∫, as shown in Figure 5.In summary, we found that the glycolipid nanotube could be a good candidate for a cytomimetic tubule in terms of its mechanical properties. Moreover, exploiting the moderate rigidity, we have developed a novel but simple aligning method: a fine line of the single nanotube is drawn freely simply by microextruding the aqueous dispersion on glass plate. Our manipulation methodology promises to open up fascinating possibilities for lipid nanotubes beyond only a substitute for microtubules; for example, a nanoneedle could be realized by extruding half of the single nanotube and fixing it at the tip of a microextrusion needle; also bridging or branching of the nanotubes on glass or metal substrates might be used as a mold for the formation of a wire and hub inside them, in molecular electronic devices; lastly, a single nanotube channel and its assembled array should provide 1D nanospace for the separation of advanced macromolecules beyond the submicro total analysis system (submTAS). Experimental SectionPreparation of single lipid nanotubes: These were prepared in water through self-assembly of renewable-resource-based, synthetic glycolipid cardanyl-b-d-glucopyranoside, which is a mixture of 1-O-3'-n-(8'(Z),11'(Z), 14'-pentadecatrienyl)-phenyl-b -d-glucopyranoside (ca. 29 wt %), 1-O-3'-n-(8'(Z),11'(Z)-pentadecadienyl) phenyl-b-dglucopyranoside (ca. 16 wt %), 1-O-3'-n-(8'(Z)-pentadecenyl) phenylb-d-glucopyranoside (ca. 50 wt %), and 1-O-3'-n-(pentadecyl) phenyl-b-d-glucopyranoside (ca. 5 wt %), as reported elsewhere. [17] Nanotube structures with 10±15 nm inner diameter and high axial ratios were confirmed by TEM, field-emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy, and atomic force microscopy (AFM). On the basis of X-ray diffraction studies, the tubular membrane wall consists of three to four interdigitated lipid bilayers. Combination of a hydrogen-bond network between the glucose headgroups, p±p stacking interactions between phenyl rings, and hydrophobic interactions between long alkyl chains are responsible for the stabilization of noncovalently formed nanotube architectures.

Aluminium(III) porphyrin-carboxylate complexes, including a porphyrin pentamer, have been characterised by NMR spectroscopy, MALDI spectrometry and single crystal X-ray diffraction; these complexes can also be coordinated by a sixth, nitrogenous, ligand to the aluminium(III) centre.

The development of stretchable electronic devices that are soft and conformable has relied heavily on a single material—polydimethylsiloxane—as the elastomeric substrate. Although polydimethylsiloxane has a number of advantageous characteristics, its high gas permeability is detrimental to stretchable devices that use materials sensitive to oxygen and water vapor, such as organic semiconductors and oxidizable metals. Failing to protect these materials from atmosphere‐induced decomposition leads to premature device failure; therefore, it is imperative to develop elastomers with gas barrier properties that enable stretchable electronics with practical lifetimes. Here, butyl rubber—a material with an intrinsically low gas permeability traditionally used in the innerliners of tires to maintain air pressure—is reinvented for stretchable electronics. This new material is smooth and optically transparent, possesses the low gas permeability typical of butyl rubber, and vastly outperforms polydimethylsiloxane as an encapsulating barrier to prevent the atmospheric degradation of sensitive electronic materials and the premature failure of functioning organic devices. The merits of transparent butyl rubber presented here position this material as an important counterpart to polydimethylsiloxane that will enable future generation stretchable electronics.

This Communication describes a simple, low-cost method of fabricating mechanically flexible, patterned metal films for use in lightweight, flexible electronic devices such as conformal displays and wearable electronics, and in bioelectronic devices such as sensors and artificial nerves, skins and muscles. Our method uses microcontact printing to define a chemical pattern on an elastomeric substrate (poly(dimethylsiloxane) (PDMS)); this pattern directs the deposition of metal on the PDMS surface from an electroless deposition (ELD) solution. Using microcontact printing for pattern formation instead of conventional photolithography and selective ELD to deposit the metal films instead of physical vapour deposition (PVD) simplifies the fabrication procedure and significantly reduces fabrication costs. We demonstrate the process by fabricating patterned copper films on PDMS surfaces with minimum feature sizes of 2 lm over substrates that are 2-3 cm 2 . These metal-elastomer composites can withstand linear strains of up to 52 % without a loss of conductivity and function as conformable electrical contacts in an organic lightemitting device (OLED).Integrating metals with elastomers is an effective way to create flexible conductors. PDMS is often the elastomer of choice because it is commercially available, electrically insulating, durable, and biocompatible. Embedding conductive particles such as carbon nanotubes or carbon black in PDMS is a simple method to make conductive, flexible interconnects, but these composites suffer from low conductivity relative to metal.[1] Both high conductivity and mechanical flexibility result from microfabricating metal wires on the surface of PDMS or enclosing electroplated wires in PDMS. Stretching these composites fractures the metal films and interrupts the flow of current. The conductivity returns with the resumption of metal-metal contact at the fracture site when the strain is released. [2,3] The amount of linear strain that the metal-elastomer composite can withstand before a loss of conductivity depends on the shape of the metal film: Lacour et al. reported that stretching the PDMS substrate by 25 % before depositing the metal wires caused undulations perpendicular to the PDMS surface to form in the gold film and yielded wires that remained conductive when stretched up to 100 % linear strain; [2a] PDMS substrates that had not been prestretched failed at 23 % linear strain.[2b] Gray et al. used tortuous wire geometries to maximize the strain: whereas linear wires lost their conductivity at 2.4 % strain, tortuous wires remained conductive at strains up to 54 %.[3]The unresolved problem with patterned metal-elastomer composites is the cost and complexity associated with depositing and patterning the metal films. Fabrication strategies generally rely on PVD of metals and photolithography, both of which are slow processes that bear high capital and operating expenses and require specialized equipment. For example, Gray et al. [3] and Maghribi et al. [4] both used electroplating to f...

Formation of a [3]catenane containing dibenzo-24-crown ether wheels and a large dipyridiniumethane ring is templated by formation of a host-guest adduct between the [3]catenane and the external crown ether.

Luminescence spectroscopy provides evidence for the efficient photoinduced energy transfer between the Ru II -based metal-to-ligand chargetransfer (MLCT) chromophore and anthracene moieties in two multicomponent, rack-type species that contain Ru II -polypyridine and anthracene subunits. Furthermore, the direction of such an energy transfer can be controlled: the energy-transfer process occurs from the Ru-based chromophore to the anthracene in a rigid matrix at 77 K, whilst in fluid solution at room temperature it occurs from the anthracene subunit to the Ru-based chromophore. The switch in the direction of the energy-transfer process arises from the quite different intrinsic lifetimes of the luminophores and the relatively small energy gap between the lowest energy excited states located in each subunit. The combination of such properties allows a thermal activation of an uphill energy transfer which switches the direction of the intercomponent process. This finding is of interest for the design, based on this relatively unexplored photophysical property, of novel artificial supramolecular systems that are capable of processing information at the molecular level.

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