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Along with enhanced dielectric permittivity and suppressed dielectric loss, PVDF-ZnO@ZnSnO3 films showed simultaneous enhancement in electrical energy storage density and storage efficiency compared to PVDF-ZnSnO3 composites.

The paper deals with the fabrication of sol-gel-derived superhydrophobic films on glass based on the macroscopic silica network with surface modification. The fabricated transparent films were composed of a hybrid -Si(CH(3))(3)-functionalized SiO(2) nanospheres exhibiting the desired micro/nanostructure, water repellency, and antireflection (AR) property. The wavelength selective AR property can be tuned by controlling the physical thickness of the films. Small-angle X-ray scattering (SAXS) studies revealed the existence of SiO(2) nanoparticles of average size ∼9.4 nm in the sols. TEM studies showed presence of interconnected SiO(2) NPs of ∼10 nm in size. The films were formed with uniformly packed SiO(2) aggregates as observed by FESEM of film surface. FTIR of the films confirmed presence of glasslike Si-O-Si bonding and methyl functionalization. The hydrophobicity of the surface was depended on the thickness of the deposited films. A critical film thickness (>115 nm) was necessary to obtain the air push effect for superhydrophobicity. Trimethylsilyl functionalization of SiO(2) and the surface roughness (rms ≈30 nm as observed by AFM) of the films were also contributed toward the high water contact angle (WCA). The coated glass surface showed WCA value of the droplet as high as 168 ± 3° with 6 μL of water. These superhydrophobic films were found to be stable up to about 230-240 °C as confirmed by TG/DTA studies, and WCA measurements of the films with respect to the heat-treatment temperatures. These high water repellant films can be deposited on relatively large glass surfaces to remove water droplets immediately without any mechanical assistance.

The fabrication of black and electrically conducting films on glass substrate derived from covalently functionalized reduced graphene oxide (FRGO) has been reported in this work. Graphene oxide (GO) was first prepared following the Hummers method and then functionalized using an organically modified silicon alkoxide, 3-glycidoxypropyltrimethoxysilane (GLYMO) in an ordered fashion. Catalyst (aluminium acetylacetonate) induced selective polymerization of the epoxy groups of GO and GLYMO was found to occur via the formation of ethereal (-C-O-C-) linkages. The formation of such linkages was confirmed by IR, Raman, TGA, X-Ray diffraction and TEM studies. Finally the functionalized graphene oxide (FGO) films were subjected to thermal reduction in an inert (N 2 ) atmosphere to obtain FRGO films. These hard FRGO films are electrically conducting and appeared as black coatings on glass. By varying the loading (20-30 wt%) of GO with the covalently bonded organically modified silica, the sheet resistance values can be tuned in a linear way from 0.8 Â 10 6 to 1.4 Â 10 3 U , À1 . The uniform current-voltage (I-V) characteristics of the films can be nicely correlated with the sheet resistance values.