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Transparent conductors for the next generation of soft electronic devices need to be highly stretchable, conductive, and transparent, while an inevitable challenge lies in enhancing them simultaneously. Cost-effective silver nanowires (AgNWs) are widely used but the conventional random network yields a high junction resistance as well as degraded conductivity in the stretched state. Here, a novel, facile, and versatile agitation-assisted assembly approach is reported to control the orientation direction and density of AgNWs and to layer-by-layer deposit the AgNWs monolayer or multilayers onto the prestrained soft substrate. This electrode demonstrates an unprecedented low sheet resistance of 2.8 Ω sq −1 as well as high transparency of 85% and high stretchability of 40%. It is interesting to note that contrary to most other reports, such a device shows higher conductivity in the stretched state compared to the released state. ] for comparison. The designed oriented AgNWs films exhibit relatively lower sheet resistance, higher or comparable transparency and stretchability simultaneously. b) Photograph of the illuminated LED biased at 3 V with our AgNWs-based electrode at the released state (left); photograph of the illuminated LED biased at 3 V using our AgNWs-based electrode when it was stretched for 40% (right). c) Photograph of the illuminated LED biased at 3 V using our AgNWs-based electrode when it was bended for about 180°.

The present article focuses on the build-up and the properties of oriented silver nanowire monolayer films and Layer-by-Layer assembled multilayer films. We describe the template-free oriented spray-assisted assembly of silver nanowires at solid/air-interfaces using Grazing Incidence Spraying, a simple and versatile approach that allows the formation of highly oriented thin films with a tunable density and in-plane orientation. Depending on the spraying conditions the nematic order parameter, which describes the angular spread of misaligned nanowires, can be as high as 0.98 (a value of 1.00 corresponding to a perfectly parallel alignment). The combination with the Layer-by-Layer assembly allows building multilayer thin films possessing in-plane anisotropy. In order to demonstrate that the local alignment does not cancel out on the macroscopic scale but leads to direction-dependent properties, we use linearly polarized UV-Vis-NIR spectroscopy to probe the selective excitation of the transverse and longitudinal localized plasmon resonances of the nanowires. The polarization efficiency of the thin films increases strongly with the in-plane density, the degree of orientation, and the number of silver nanowire layers. Multilayer films containing 4 layers of nanowires oriented in the same direction reach a polarization efficiency of up to 97% in the near-infrared region.

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One-dimensional (1D) nanoobjects have strongly anisotropic physical properties which are averaged out and cannot be exploited in disordered systems. We reviewed the in plane alignment approaches and potential applications with perspectives shared.

Chirality is found at all length scales in nature, and chiral metasurfaces have recently attracted attention due to their exceptional optical properties and their potential applications. Most of these metasurfaces are fabricated by topdown methods or bottom-up approaches that cannot be tuned in terms of structure and composition. By combining grazing incidence spraying of plasmonic nanowires and nanorods and Layer-by-Layer assembly, we show that nonchiral 1D nanoobjects can be assembled into scalable chiral Bouligand nanostructures whose mesoscale anisotropy is controlled with simple macroscopic tools. Such multilayer helical assemblies of linearly oriented nanowires and nanorods display very high circular dichroism up to 13 000 mdeg and giant dissymmetry factors up to g ≈ 0.30 over the entire visible and near-infrared range. The chiroptical properties of the chiral multilayer stack are successfully modeled using a transfer matrix formalism based on the experimentally determined properties of each individual layer. The proposed approach can be extended to much more elaborate architectures and gives access to templatefree and enantiomerically pure nanocomposites whose structure can be finely tuned through simple design principles.

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