Honeycomb films with various building units, showing potential applications in biological, medical, physicochemical, photoelectric, and many other areas, could be prepared by the breath figure method. The ordered hexagonal structures formed by the breath figure process are related to the building units, solvents, substrates, temperature, humidity, air flow, and other factors. Therefore, by adjusting these factors, the honeycomb structures could be tuned properly. In this review, we summarized the development of the breath figure method of fabricating honeycomb films and the factors of adjusting honeycomb structures. The organic-inorganic hybrid was taken as the example building unit to discuss the preparation, mechanism, properties, and applications of the honeycomb films.

Abstract-With the advancement of wireless networks and cloud computing, people are becoming increasingly surrounded by a variety of displays -rich electronic devices: TV, Phone, Pad, Notebook and other portable or wearable devices. These electronic products put high demands on the quality of the visual interface. Paper-like displays are reflective and do not require a backlight. They have received much attention after electrophoretic-based electronic paper displays were commercialized in 2004. Paper-like displays combine excellent reading experience with ultra-low power consumption. In particular, their outdoor readability is superior to transmissive liquid crystal displays (LCDs) and organic light emitting devices (OLEDs). In this paper, we give an overview on various paper-like display technologies with emphasis of the status and future development of electrophoretic display and electrofluidic display principles. We focus on both technologies because electrophoretic displays have been commercialized successfully, and electrofluidic display has high potential to deliver video and full color.

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Silicon nanowires (SiNWs) are widely used as photocathodes because of their large electrochemically available surface-area density and inherent ability to decouple light absorption from the transport of minority carriers. In order to minimize overpotential for solar-driven hydrogen (H) production, a combination of an ultrathin molybdenum disulfide (MoS) layer with SiNWs as photocathode has attracted much attention. Herein, for the first time, this study presents the synthesis of a composite photocathode via direct growth of ultrathin MoS nanosheets on SiNWs (referred to as SiNWs/MoS) by one-step chemical vapor deposition (CVD). Due to the high surface-area density of the arrays of SiNWs, the discontinuous MoS nanosheets grown on the SiNWs achieved a much higher density of active sites. Moreover, the coating of MoS on the SiNWs was found to protect the photocathode during the photoelectrochemical (PEC) reaction. A high efficiency with photocurrent j of 16.5 mA cm (at 0 V vs. reversible hydrogen electrode) and an excellent stability over 48 h of PEC operation were achieved under a simulated 1 sun irradiation.

We report a new top-down nanofabrication technology to realize large area metal nanowire (m-NW) arrays with tunable sub-20 nm separation nanogaps without the use of chemical etching or milling of the metal layer. The m-NW array nanofabrication technology is based on a self-regulating metal deposition process that is facilitated by closely spaced and isolated heterogeneous template surfaces that confine the metal deposition into two dimensions, and therefore, electrically isolated parallel arrays of m-NW can be realized with uniform and controllable nanogaps. Au-NW and Ag-NW arrays are presented with high-density ~10(5) NWs cm(-1), variable NW diameters down to ~50 nm, variable nanogaps down to ~5 nm, and very large nanogap length density ~1 km cm(-2). The m-NW arrays are designed and implemented as interdigitated nanoelectrodes for electrochemical applications and as plasmonic substrates where the coupled-mode localized surface plasmon resonance (LSPR) wavelength in the nanogaps between adjacent m-NW dimers can be precisely tuned to match any excitation source in the range from 500 to 1000 nm, thus providing optimal local electromagnetic field enhancement. A spatially averaged (n = 2500) surface-enhanced Raman scattering (SERS) analytical enhancement factor of (1.2 ± 0.1) × 10(7) is demonstrated from a benzenethiol monolayer chemisorbed on a Au-NW array substrate with LSPR wavelength matched to a He-Ne laser source.

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The construction of ordered nanoparticle arrays is important for nanophotonics and sensing applications. We report a facile technology for continuous-flow fabrication of particle-laden plasmonic microcapsules (PLPMs) by combining droplet microfluidics, nanoparticle self-assembly and thin film deposition. The metallic hierarchical nanostructures on PLPMs are presented with high-density "hot-spot" scattering sites with the nanoarray pitch and gap distance being controlled by the deposited metal film thickness and nanoparticle size. The noble metal "hot-spots" show high, localized surface plasmon resonance according to the near-field electromagnetic field enhancement. Surface-enhanced Raman scattering (SERS) analytical enhancement factors of >10 can be obtained with good reproducibility using 4-methylbenzenethiol (4-MBT) as a probe molecule and Au or Ag as the metal layer. The droplet microfluidics platform enables continuous generation of homogeneous microcapsules with high frequency. This proposed strategy therefore combines advantages from both top-down (creation of microdroplets and deposition of the metal film) and bottom-up (self-assembly of nanoparticles) processes with flexibility in material selection (nanoparticles and polymer) and structure scaling (metal layer thickness, nanoparticle size and microcapsule size). Therefore, it provides a fast and reliable method of producing plasmonic microsensors.

A stable and scalable polymer-stabilized liquid crystal window which electrically switches from transparent to opaque has been fabricated. Scanning electron microscope measurement shows that higher polymer concentration will induce denser polymer network in polymer stabilized liquid crystal system and then stronger anchoring force between polymer network and liquid crystal molecules, which resulting in larger operating voltage. The cell with larger cell gap has a lower saturated transmittance in the voltage-on state, which attributed to a larger number of scattering domains in thick cell. The optimized cell exhibits a highly transparent voltageoff state (3.5% haze) and a voltage-on scattering state (98% haze) with the threshold voltage of around 20 V. The durability test shows that the optical device switches at least 100,000 times without degradation of optical contrast and shows a high temperature tolerance. Meanwhile, a 40 × 50 cm 2 window has been developed in an industrial production line showing the same optical properties. Our results demonstrate the fabrication of smart windows with a highly transparent rest state and high optical contrast on a commercial mass production scale, making them attractive for applications in buildings, automobiles, and switchable sunglasses for light management and potentially energy saving.