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Core-shell structured barium titanate-poly(glycidyl methacrylate) (BaTiO3-PGMA) nanocomposites were prepared by surface-initiated atom transfer radical polymerization of GMA from the surface of BaTiO3 nanoparticles. Fourier transform infrared spectroscopy confirmed the grafting of the PGMA shell on the surface of the BaTiO3 nanoparticles cores. Transmission Electron Microscopy results revealed that BaTiO3 nanoparticles are covered by thin brushes (∼20 nm) of PGMA forming a core-shell structure and thermogravimetric analysis results showed that the grafted BaTiO3-PGMA nanoparticles consist of ∼13.7% PGMA by weight. Upon incorporating these grafted nanoparticles into 20 μm-thick films, the resultant BaTiO3-PGMA nanocomposites have shown an improved dielectric constant ( ε = 54), a high breakdown field strength (∼3 MV/cm) and high-energy storage density ∼21.51 J/cm3. AC conductivity measurements were in good agreement with Jonscher's universal power law and low leakage current behavior was observed before the electrical breakdown field of the films. Improved dielectric and electrical properties of core-shell structured BaTiO3-PGMA nanocomposite were attributed to good nanoparticle dispersion and enhanced interfacial polarization. Furthermore, only the surface grafted BaTiO3 yielded homogenous films that were mechanically stable. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 719-728 [ABSTRACT FROM AUTHOR]

Summary: Thin films of vertically aligned tungsten nanorods were used to enhance field ionization in pyroelectric crystal D–D fusion experiments resulting in increased neutron production. The tungsten nanorods were deposited on a single LiTaO3 crystal using sputter deposition at glancing angles. The combination of a single tungsten tip with a thin film of nanorods on the face of the crystal yielded about four times the number of neutrons than did either a single tip or nanorods alone. [Copyright &y& Elsevier]

We report the self-assembly of ZnOx (0≤x≤1) (and permalloy) nanoclusters into hollow nanoparticles using pulsed laser ablation of bulk Zn (or permalloy) in ethanol-water binary mixture. The self-assembly is due to the trapping of laser-produced nanoclusters by the interfaces of cavitation bubbles and the bonding of the nanoclusters by capillary attraction. It was found that the bubbles generated in the mixture have significantly longer lifetimes compared to water alone, which provide an increasing chance to absorb diffusive nanoclusters. The mixture could be adjusted by adding viscous surfactant that makes the pulsed laser ablation in liquid a promising method for the discovery and fabrication of other hollow geometries. [ABSTRACT FROM AUTHOR]