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Herein, thermochromic superhydrophobic coatings (TSCs) with different colors are prepared, and their surface wettabilities and optical properties are studied. The TSC coating maintains its surface superhydrophobicity even after a series of mechanical damage (sandpaper abrasion, gravel impact, and knife scratching), chemical corrosion, ultraviolet aging, and environmental temperature changes. Contaminants on the surface of the coating sre easily washed by water droplets. The TSC has a reversible color function with a critical discoloration temperature (Tc) approximately in the range 28–31 °C. In winter, the ambient temperature (Ta) is lower than Tc, and the TSC is dark and absorbs more solar energy. Although in summer, Ta > Ta, the TSC is light and reflects more solar energy. The sunlight exposure test shows that the surface temperature of the thermochromic pigment/polydimethylsiloxane (TP/PDMS) coating in winter is only 0.9 °C lower than that of the carbon black/PDMS (CB/PDMS) coating, whereas in summer, the surface temperature of the TP/PDMS coating is only 6.2 °C higher than that of TiO2/PDMS coating. Energy consumption simulation results show that the TP/PDMS coating decreases the total annual energy consumption in North China by 13.74% compared with the traditional white cooling coating. [ABSTRACT FROM AUTHOR]

With the continuous development of bionics, such as, geckos and virginia creeper with both superhydrophobic and super‐adhesive, the surface wetting and super‐adhesive properties of various porous materials have attracted extensive attention of the scientific and medical communities. Here, the honeycomb polyurethane (PU) porous films with strong adhesion were successfully prepared by microphase separation method and the effects of growth parameters on their microstructure and adhesive strength to ice were investigated. It was found that a high relative humidity (e.g., 100%) and a low solution concentration (e.g., 2%) facilitated the formation of ordered honeycomb PU porous films, and as‐prepared PU pores with average pore diameter as small as 5 μm are better ordered and more uniform than these in related documents. Although the contact angle of water droplets on the surface of PU porous films increased from the premodification value of 85–130° to more than 160° after surface modification with polydopamine (PDA), the corresponding rolling angle remained approximately constant (180°), indicating that the surface of PU porous films has strong adhesion similar to geckos and virginia creeper. Furthermore, at lower temperature, the PU porous films exhibited the high adhesive strength of 142.13 kPa on ice, which was strongly dependent on the porous microstructures and surface compositions. The improved adhesive behavior to ice of honeycomb PU porous films modified with PDA provides new strategies for surface modification of materials and potential applications in medical domain. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces with both excellent mechanical durability and easy reparability based on polytetrafluoroethylene/room temperature vulcanized silicone rubber (PTFE/RTVSR) composites were prepared by a simple abrading method. The surface energy of RTVSR matrix decreased with the increasing volume fraction of PTFE particles, and the surface rough microstructures of the composites were created by abrading. A water droplet on the surface exhibited a contact angle of about 165° ± 3.4° and a sliding angle of about 7.3° ± 1.9°. Such superhydrophobic surfaces showed strong mechanical durability against sandpaper because the surfaces were prepared in the way of mechanical abrasion, and the fresh exposed surfaces were still superhydrophobic. In addition, the micro-structures on the elastic surface of the composite will be compressed by elastic deformation to avoid being broken during the friction cycles when cotton fabric was used as an abrasion surface. The deformation will rebound to renew the original surface structures when the load is withdrawn. Therefore, the elastic PTFE/RTVSR composites are of advantage to construct superhydrophobic surfaces with better abrasion resistance. More importantly, such superhydrophobicity can be repaired by a simple abrading regeneration process within a few minutes when the surface is damaged or polluted by organic contaminant. [ABSTRACT FROM AUTHOR]

The electron work function (EWF) is an important parameter of a semiconductor. The understanding of the correlation between the EWF and surface morphology is of much significance for revealing related photoelectric mechanisms. In this study, the surface of indium tin oxide (ITO) was treated by chemical corrosion or absorption of copper phthalocyanine molecules, and their changes in EWF were systematically investigated using scanning Kelvin probe. The decrease of the EWF with the increase of surface roughness was found. Based on a microcapacitor model, the correlation between the EWF and surface microstructures was built up, which was well consistent with the experimental results. These data are of help for improving the photoelectric behaviors of ITO-based devices by adjusting surface/interface structures. [ABSTRACT FROM AUTHOR]

We report the preparation and dielectric properties of ceramic-polymer composites using Ba0.95Ca0.05Ti0.8Zr0.2O3 (BCTZ) as a ceramic filler and polyethersulfone (PES) as a polymer matrix. The BCTZ powders were synthesized by a sol-gel method to fabricate BCZT-PES composites. The composites with various BCTZ volume fractions were prepared by a solution mixing and hot-pressing method. The composite with 50 vol % BCTZ showed high dielectric constant ([variant_greek_epsilon]=48.80) and low loss (tan δ=0.042) at 1 kHz and room temperature. Such excellent dielectric properties of the composites displayed an acceptable stability within a wide range of temperature (from 20 to 150 °C) and frequency (from 100 Hz to 100 kHz). The present work indicates that the BCTZ-PES composite can be a candidate for embedded capacitors. [ABSTRACT FROM AUTHOR]