Stretchable light‐emitting diodes (LEDs) and electroluminescent capacitors have been reported to potentially bring new opportunities to wearable electronics; however, these devices lack in efficiency and/or stretchability. Here, a stretchable organometal‐halide‐perovskite quantum‐dot LED with both high efficiency and mechanical compliancy is demonstrated. The hybrid device employs an ultrathin (<3 µm) LED structure conformed on a surface‐wrinkled elastomer substrate. Its luminescent efficiency is up to 9.2 cd A−1, which is 70% higher than a control diode fabricated on the rigid indium tin oxide/glass substrate. Mechanical deformations up to 50% tensile strain do not induce significant loss of the electroluminescent property. The device can survive 1000 stretch–release cycles of 20% tensile strain with small fluctuations in electroluminescent performance.

The development of intrinsically stretchable electronics poses great challenges in synthesizing elastomeric conductors, semiconductors and dielectric materials.

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Paper has remained the world's most-widely accessible information medium even as sustainable and reusable paper replacements have attracted increasing attention. Here, an ink-free rewritable paper concept is developed that combines recent developments in photonic crystals, shape memory polymers, and electroactive polymers in a nanocomposite that matches the benefits of paper as a zero-energy, long-term data storage medium, but provides the additional advantage of rewritability. The rewritable paper consists of a ferroferric oxide-carbon (Fe 3 O 4 @C) core-shell nanoparticle (NP)-based photonic crystal embedded in a bistable electroactive polymer (BSEP). Electrical actuation induces large deformation in the z-axis of the nanocomposite, creating distinct color change in the actuated area. This nanocomposite stores high fidelity color images without inks, the images remain stable after more than a year of storage in ambient conditions, and the stored images can then be rewritten over 500 times without degrading. A seven-segment numerical display is also demonstrated.

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Special attention has been paid to nanotubes and nanowires due to their interesting properties and potential applications. Since the discovery of carbon nanotubes [1] various nanotubes such as WS 2 , MoS 2 , BN, BC 2 N, and semiconductor nanowires such as CdTe and ZnCdSe have been synthesized. [2±7] The template technique is an important method of nanowire fabrication. Usually, there are two types of template: ªtrack-etchº polymer membranes, such as the polycarbonate membrane with 60 nm diameter pores, and the porous aluminum oxide membrane, with a pore diameter of 70 nm. [8,9] However, the challenges of fabricating semiconductor nanowires with a quantum confinement effect are great because technically useful quantum wires will require lateral dimensions less than 10 nm, and it is difficult to fabricate quantum wires on a scale lower than 10 nm. [10] Nanocables with a wire/sheath structure are another kind of potentially useful one-dimensional nanostructure. There have been a few reports on the preparation of semiconductor/insulator nanocables. For example, Si/SiO 2 nanocable has been prepared by combining laser-ablation cluster formation with vapor±liquid±solid (VLS) growth, [11] and b-SiC/SiO 2 nanocable has been obtained by the carbothermal reduction of sol±gel derived silica xerogels containing carbon nanoparticles at 1650 C. [12] In both cases, the outer layers of SiO 2 in nanocables are induced by the reaction atmosphere.In this communication, we design a new strategy for synthesizing a semiconductor/polymer nanocable in a heterogeneous solution system. In this system, an organic monomer with polar groups can self-organize into amphiphilic supramolecules, utilizing the difference in solubility of different fragments in the monomer molecule. Such supramolecules can polymerize to a pre-organized polymer tubule with a hydrophilic core and a hydrophobic sheath. Then the polymer tubule acts as both template and nanoreactor for the following growth of inorganic semiconductor nanowires in the hydrophilic cores from various water-soluble sources. Thus, a nanocable with semiconductor wire in a polymer sheath can be obtained. In this approach, g-irradiation offers an ideal means by which the supramolecules can be polymerized and the tubular structure can be solidified with the desired diameter at room temperature under ambient pressure.Based on the above strategy, a CdSe/poly(vinyl acetate) (PVAc) nanocable with a 6 nm core and an 80 nm diameter sheath was successfully synthesized from a heterogeneous system of vinyl acetate (VAc) monomer, cadmium sulfate (CdSO 4 ×8/3H 2 O), and sodium selenosulfate (Na 2 Se-SO 3 ) under g-irradiation at room temperature and ambient pressure. Appropriate amounts of analytically pure CdSO 4 [8/3H 2 O, Na 2 SeSO 3 , and isopropanol were dissolved in distilled water in a ground-glass stoppered flask, then mixed with VAc. Sodium selenosulfate can be synthesized by refluxing selenium powders in a sodium sulfite (Na 2 SO 3 ) solution according to the literature. [13] Isopropanol was used...