A mixture of bulk hexagonal boron nitride (h-BN) with hydrazine, 30% H(2)O(2), HNO(3)/H(2)SO(4), or oleum was heated in an autoclave at 100 °C to produce functionalized h-BN. The product formed stable colloid solutions in water (0.26-0.32 g L(-1)) and N,N-dimethylformamide (0.34-0.52 g L(-1)) upon mild ultrasonication. The yield of "soluble" h-BN reached about 70 wt%. The dispersions contained few-layered h-BN nanosheets with lateral dimensions in the order of several hundred nanometers. The functionalized dispersible h-BN was characterized by IR spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV/Vis spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). It is shown that h-BN preserves its hexagonal structure throughout the functionalization procedure. Its exfoliation into thin platelets upon contact with solvents is probably owing to the attachment of hydrophilic functionalities.

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A simple model of a dry reversed micelle of ionic surfactants is proposed, according to which during the optimization procedures the ions move over certain closed surfaces in a vacuum at T = 0 K .The electrostatic interactions of discrete ions in dry, reversed micelles of AOT are calculated as a function of the sizes of the ions, ion charges, and the optimum positions of the ions in the polar cavity of the micelles. It is shown that when the counterions penetrate the layer of the potential-determining ions, the electrostatic interaction begins to favor the self-organization of the ionic surfactants over that of the reversed micelles. The distribution of the electrostatic potential in the polar cavity of micelles of different shapes (a sphere, a spheroid, a prolate ellipsoid) is calculated. In the models in which the charge is taken to be discrete, the electrostatic field extends beyond the double electric layer (DEL); the sign of the potential coincides with that of the counterion. It is shown that in the analysis of structures of dry, reversed micelles the possibility of the formation of voids (in the surface layer of polar groups and in the center) as well as the density of packing should be taken into account by using a specially developed approach. The most probable structural parameters of AOT micelles are determined for different counterions (Li+, Na+, Cs+, [Co(H2O)6]2+, La3+).

Bulk NbS3and NbSe3were stably dispersed in a number of organic solvents to yield colloids containing thin well-crystallized nanoribbons of NbS3and NbSe3.