HREM study of Fe—pillared smectite

Abstract

During the process of pillaring smectite, a metal oxide precursor is introduced into the interlayer space of the layered clay mineral. By subsequent heating of the precursor, a metal oxide forms, increasing the interlayer spacing 0.5—1.0 nm, as observed in XRD.Pillaring of clays increases the active surface area, and the materials may find use as molecular sieves and catalysts.Most of the information on the oxide pillars has been derived from indirect spectroscopic and structural methods. In the present study we have used HREM to obtain direct evidence for the pillar formation.