Stoichoimetric graphene fluoride monolayers are obtained in a single step by the liquid-phase exfoliation of graphite fluoride with sulfolane. Comparative quantum-mechanical calculations reveal that graphene fluoride is the most thermodynamically stable of five studied hypothetical graphene derivatives; graphane, graphene fluoride, bromide, chloride, and iodide. The graphene fluoride is transformed into graphene via graphene iodide, a spontaneously decomposing intermediate. The calculated bandgaps of graphene halides vary from zero for graphene bromide to 3.1 eV for graphene fluoride. It is possible to design the electronic properties of such two-dimensional crystals.

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The synthesis of Cu nanoparticles (NPs) via the reduction of Cu ions with sodium borohydride in the presence of sodium polyacrylate is presented. The final Cu nanocrystals having a 14 nm diameter were generated via the aggregation and coalescence of the primarily formed ultrasmall particles (approx. 3 nm). Addition of sodium sulfite to the dispersions provided the protection of the Cu NPs against oxidation. On the other hand, the controlled aeration of the Cu NPs resulted in their transformation to Cu 2 O nanocubes with an average size of 18 nm. Both Cu NPs and Cu 2 O nanocubes can effectively catalyze reduction of 4-nitrophenol by sodium borohydride in aqueous solution.

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