Small-angle neutron scattering from a nano-layered synthetic silicate

• Published in: Physica. B, Condensed matter Condensed matter, 2004-10, Vol.352 (1-4), p.247-258
• Main Authors: Knudsen, K.D., Fossum, J.O., Helgesen, G., Haakestad, M.W.
• Format: Article
• Language: English
• Subjects: Clay; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Neutron diffraction and scattering; Physics; Pressure effect; Small-angle neutron scattering; Structure of solids and liquids; crystallography; Water absorption
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2004.07.018

The combined analysis of the power-law behavior of small-angle scattering and of the relative scattered intensity for different scattering vectors makes it possible to obtain information on both surface roughness and shape of pores in layered silicates. It was found that low and moderate pressures of compression (up to 2.6MPa) during the sedimentation stage of preparation of packed dehydrated fluorohectorite has little effect on the final small-angle scattering behavior and thus on the pore characteristics of the samples used in this study. The anisotropically shaped pores showed an average correlation length ratio of approx. 1:2 between the direction of axial compression and the direction perpendicular to this, and the pore structure seems to be determined mainly by the characteristics of the clay platelets themselves (aspect ratio, polydispersity), and less by the pressure applied during sedimentation. However, some indication of increased irregularities, possibly linked to deformation or fracture of parts of the clay grains, is observed at the highest pressure used (26MPa).