Internal structure of magnetic porous glasses and the related ferroelectric nanocomposites

The internal structure of empty porous micro- and macroporous magnetic glasses and the related nanocomposites containing NaNO$_{2}$ and KNO$_{3}$ embedded in pores of the glasses has been investigated using small-angle neutron scattering. The characteristic sizes of magnetite particles in matrices and the sizes of nanoparticles embedded in ferroelectric materials have been estimated. It has been shown that, for microporous glasses in the momentum transfer range 0.35 nm$^{-1}$ $<Q<$ 1.7 nm$^{-1}$, the dependence of the small-angle neutron scattering intensity on the momentum transfer has two characteristic regions: the first region corresponds well to the Porod’s law $Q^{-4}$ (smooth surface), and the second region is consistent with the mass fractal reflecting the internal structure of channels in the microporous glass. For macroporous glasses over the entire momentum transfer range 0.35 nm$^{-1}$ $<Q<$ 1.7 nm$^{-1}$, the scattering intensity is described by the dependence $I(Q)\sim Q^{-n}$ c $\alpha$ = 3.96 $\pm$ 0.02; i.e., in these glasses, there is a system of channels with sufficiently smooth surfaces.