Light absorption of graphene plays an important role in optoelectronic applications. In this work, a series of reduced graphene oxide (RGO) dispersions containing flakes with various configurations are prepared, and their optical absorption coefficients are investigated. Our results suggest that the lateral size distribution, the mean number of layers per flake and the functional groups on RGO are all important factors influencing the absorption coefficient. We find the dispersion with a larger amount of small flakes (≤600 nm), as well as less layers per flake, gives a smaller absorption coefficient at 660 nm. Essentially, functional groups grafted on graphene flakes promote an eminent role in the absorption coefficient.

We report a facile and effective technique for the large-scale production of nano-sized graphene sheets via subjecting the microcrystalline graphite to ball milling. The products consist of single-or few-layer (#5 layers) graphene with lateral dimensions concentrated in the range of 100-200 nm. It displays a high intensity of photoluminescence at a wavelength of 339 nm and graphene dispersions at concentrations up to 1.22 mg ml À1 .

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Nanosized tungsten carbide (nanoWC) has been widely studied and applied in many industries as hard materials since it has good combination of high hardness and strength. Thermal mechanical alloying method consisting of high-energy ball milling and subsequent carbonization is a common synthetic approach to prepare nanoWC. In this paper, a special milling process has been reviewed, in which the dielectric barrier discharge plasma (DBDP) is introduced, for the preparation of nanoWC. The DBDP milling renders the W+C powders with specific flake-like structure possible owing to the cooperative effect of DBDP and mechanical milling. The obtained W+C powders are activated significantly within shortened milling period. Furthermore, pure nanoWC powders can be synthesized after subsequent carbonization at a significantly lowered temperature. DBDP milling is demonstrated to be an efficient way to synthesize nanoWC.

We introduce a novel kind of submicron-sized reduced graphite oxide (μRGO) for the preparation of a transparent conducting film.