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Zinc oxide (ZnO) nanoparticles functionalized with a bi-functional coupling agent methacryloxypropyl-trimethoxysilane (MPS) were used to fabricate a vinyl-ester resin polymeric nanocomposite, which shows an improved interfacial interaction between the particle and matrix. As a result, in comparison to the unmodified particle-filled nanocomposites, the functionalized particle-filled composites possessed higher resistance to thermal degradation, and demonstrated improved UV shielding and enhanced photoluminescent properties. The more uniform particle dispersion, passivation of the particle surface with MPS and increased oxygen vacancies were justified to contribute to the increased thermal stability and the enhanced photoluminescent properties. Significant tensile strength improvement was closely related to the observed uniform particle distribution and the intimate interfacial interaction through the strong chemical bonding.

We report the first demonstration of the growth of giant graphene domains on platinum (Pt), which results in a uniform bilayer graphene film with domain sizes of millimetre scale. These giant graphene domains are attributed to the giant Pt grains attained in post-deposition annealed Pt thin films that exhibit a strong dependency on the Pt film thickness. Giant grains have been claimed to occur in other metallic materials under appropriate film thicknesses and processing conditions. Our findings demonstrate a route towards rational large-scale uniform graphene synthesis for applications in nanoelectronics and sensing.

Alumina nanoparticles were successfully functionalized with a bi-functional coupling agent, (3-methacryloxypropyl)trimethoxysilane (MPS), through a facile neutral solvent method. MPS was found to be covalently bound with the nanoparticles. The linked MPS was polymerized with a vinyl-ester resin monomer through a free radical polymerization. Atomic force microscope phase images showed a uniform distribution of nanoparticles. Microtensile test results revealed the Young's modulus and strength increasing with particle loading. Microscopic examinations revealed the presence of large plastic deformations at the micron scale in the nanocomposites in agreement with the observed strengthening effect of functionalized nanoparticles. Thermo-gravimetric analysis (TGA) did not show any significant change in the thermal degradation of the nanocomposite as compared with the neat resin. The polymer matrix effectively protected the alumina nanoparticles from dissolution in basic and acidic solutions.

Graphite nanoplatelets with thicknesses down to 2–10 nm are synthesized by alkali metal intercalation followed by ethanol exfoliation and microwave drying. Graphite that has already been intercalated and exfoliated with an oxidizing acid is reintercalated with an alkali metal to form a first stage compound, as confirmed by powder X-ray diffraction. This can be achieved either by heating graphite and potassium or caesium at 200 °C, or at room temperature using a sodium–potassium alloy. Reaction of the intercalated graphite with ethanol causes exfoliation of the graphene layers. Microwave radiation aids in drying and results in further separation of the sheets. Thermogravimetric analysis indicates that the graphite nanoplatelets are approximately 150 °C less stable in air than pristine graphite. High aspect ratio graphite nanoplatelets offer promise as reinforcements for high strength carbon–carbon composites.