Bulk quantities of hexagonal boron nitride (h-BN) nanosheets have been synthesized via a simple template- and catalyst-free chemical vapor deposition process at 1100−1300 °C. Adjusting the synthesis and chemical reaction parameters, the thickness of the BN nanosheets can be tuned in a range of 25−50 nm. Fourier transform infrared spectra and electron energy loss spectra reveal the typical nature of sp2-hybridization for the BN nanosheets. It shows an onset oxidation temperature of 850 °C for BN nanosheets compared with only about 400 °C for that of carbon nanotubes under the same conditions. It reveals a strong and narrow cathodoluminescence emission in the ultraviolet range from the h-BN nanosheets, displaying strong ultraviolet lasing behavior. The fact that this luminescence response would be rather insensitive to size makes the BN nanosheets ideal candidates for lasing optical devices in the UV regime. The h-BN nanosheets are also better candidates for composite materials in high-temperature and hazardous environments.

A versatile and general synthetic route for the synthesis of conjugated main group element-based polymers, previously inaccessible by conventional means, is reported. These polymers contain five-membered chalcogenophene rings based on S, Se, and Te, and we demonstrate that optoelectronic properties can be readily tuned via controlled atom substitution chemistry. In addition, regioregular hybrid thiophene-selenophene-tellurophene and selenophene-fluorene copolymers were synthesized to provide a further illustration of the scope of the presented metallacycle transfer/cross-coupling polymerization method.

An easy chemical route for the synthesis of (γ-Fe 2 O 3 @SiO 2 ) n @TiO 2 functional hybrid nanoparticles is reported in this paper. The hybrid nanoparticles are composed of spherical nanoparticles about 100 nm in diameter, with several γ-Fe 2 O 3 fine particles about 15 nm in diameter as cores distributing within the titania matrix and silica as coatings and barrier layers between the magnetic cores and titania shells. The (γ-Fe 2 O 3 @SiO 2 ) n @TiO 2 hybrid nanoparticles show good magnetic response and got together within 20 s in a magnetic field. Photodegradation examination of the magnetic hybrid nanoparticles was carried out in methylene blue solutions illuminated under UV light in a photochemical reactor. It is shown that the (γ-Fe 2 O 3 @SiO 2 ) n @TiO 2 functional hybrid nanoparticles are photocatalytically actived. About 80% of methylene blue decomposed in 80 min in the presence of magnetic hybrid nanoparticles under illumination of UV light. The synthesized magnetic hybrid nanoparticles display high photocatalytic efficiency and will find potential applications for cleaning polluted water with the help of magnetic separation.

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A multiresponsive supramolecular gel was constructed based on a bis­(pyridinium) dication guest and a copolymer with pillararenes as the pendant groups, which was synthesized by free radical copolymerization of methacrylate-functionalized pillararenes and methyl methacrylate. The mechanism of gel formation was explored by the intensive study. Upon addition of competitive host or guest molecules, pillararene-based gel could be transferred into sol due to the competition of host–guest complexation. Surprisingly, the ordered stacking of pillararenes was indispensable to obtain the supramolecular gel, which endowed the system with response to temperature change.