On studying nanoporous-carbon-based composites by small-angle X-ray scattering

Abstract

Possible intensity variations arising in small-angle X-ray scattering as a result of filling nanopores in nanoporous carbon with extraneous impurities were analyzed in terms of a simple monodispersed system of electron-density fluctuations. Systems with various ratios between the electron density of the carbon skeleton and that of noncarbon nanoclusters incorporated in the skeleton were considered; these systems correspond to the composites with clusters of hexagonal or amorphous selenium, as well as those of rhombic or amorphous sulfur. The partial contributions to the intensity variation in scattering from unfilled nanopores, carbon and noncarbon nanoclusters, and also the total variation were calculated as functions of nanopore filling factor β for various degrees of initial-nanoporosity α of the carbon skeleton. It was shown that, depending on α and β, both an increase and a decrease in scattering is possible. The data obtained may be useful for controlling the filling efficiency of nanopores during the formation of a composite.