A mechanically adaptable elastomer composite is prepared with reversible soft-stiff properties that can be easily controlled. By the exploitation of different morphological structures of calcium sulfate, which acts as the active filler in a soft elastomer matrix, the magnitude of filler reinforcement can be reversibly altered, which will be reflected in changes of the final stiffness of the material. The higher stiffness, in other words, the higher modulus of the composites, is realized by the in situ development of fine nanostructured calcium sulfate dihydrate crystals, which are formed during exposure to water and, further, these highly reinforcing crystals can be transformed to a nonreinforcing hemihydrate mesocrystalline structure by simply heating the system in a controlled way. The Young's modulus of the developed material can be reversibly altered from ∼6 to ∼17 MPa, and the dynamic stiffness (storage modulus at room temperature and 10 Hz frequency) alters its value in the order of 1000%. As the transformation is related to the presence of water molecules in the crystallites, a hydrophilic elastomer matrix was selected, which is a blend of two hydrophilic polymers, namely, epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer and a terpolymer of ethylene oxide-propylene oxide-allyl glycidyl ether. For the first time, this method also provides a route to regulate the morphology and structure of calcium sulfate nanocrystals in a confined ambient of cross-linked polymer chains.

The next generation of sensors requires a simple yet compact lab on chip-based precise optical detection mechanism where data interpretation can be achieved with minimum effort. Hereby, cost-efficient strategies of manufacturing both propagating surface plasmon polariton (SPP) and localized surface plasmon resonance (LSPR) sensors on flexible platforms are explored via mechanical instabilities and oblique-angled metal evaporation. Centimeter scaled dielectric grating structures produced by plasma oxidation of pre-stressed polydimethylsiloxane film have comprised the substrates, thus imparting inherent flexibility. Subsequently, both continuous and discontinuous 1D-metallic lattices are obtained via vapor deposition of gold at different angles. The optical isotropy (gold surface-grating) and anisotropy (gold edge-grating) are distinctly observed as a difference between forward and backward diffraction efficiencies, backed by analytical correlation to the observed orders. Supported with electromagnetic modeling, the SPP and LSPR excitations are experimentally characterized under reflectance and transmittance measurements, along with a demonstration of their sensing capabilities. The LSPR supported flexible sensor provides superiority in terms of sensitivity, which is investigated under mechanical deformations to exhibit consistency of the resonant wavelength. Such consistency is strategically unraveled via "finite element method" based approaches, thus providing a new paradigm of cost-efficient, large-scaled flexible sensors.

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Self-powered tactile module-based electronic skins incorporating triboelectric nanogenerator (TENG) appears to be a worthwhile alternative for smart monitoring devices in terms of sustainable energy harvesting. On top of it, ultra-stretchability...

Metallic nanostructures are highly attractive for refractive index sensing, as the evanescent field from the associated plasmonic resonances resides in close proximity to the adjacent analyte media. However, this benefit is often reduced due to broad plasmonic lineshapes producing poor quality factors. The rational design provides strategies for narrowing the plasmonic modes by incorporating photonic diffraction, which promotes surface lattice resonances . Due to the stringent parametric dependencies, these resonances in metallic lattices are not always feasible, particularly when a straightforward fabrication route with fewer process steps is desired. Herein, hybridized guided‐mode resonance in a 2D‐metallic photonic crystal slab (2D‐mPhCs) is introduced that ensures high‐quality hybrid modes while maintaining a simple fabrication methodology. In direct comparison to its constituent plasmonic and photonic modes, this concept is discussed for sensing applications. The “figure of merit (FOM)” is frequently regarded as a valid metric for measuring sensing performanceensuring high‐quality modes with an improved detection limit. The experimental results confirm enhanced FOM (three to six times) for the hybrid modes, in contrast to the constituent counterparts. For optoelectronic applications, such as photodetection and photocatalysis, these hybrid structures with high‐quality modes offer a promising platform to harvest light at the metal–semiconductor interfaces.