Abstract: This paper presents a critical overview of research progress in the synthesis, properties, structure, and applications of smectite clay-based catalytic materials. The 2:1-type layered structure of smectites, which consists of two Si-O tetrahedral sheets sandwiched by a metal-oxygen octahedral sheet, along with changeable composition of layers, exchangeable cations within interlayers, and intercalation of active species, allows numerous preparation strategies to produce a variety of clay-based catalytic materials. So far the catalytically active species intercalated into the interlayers of clays are metal ions, zero-valent metal, metal oxides, metal complexes, metal sulfides, and carbon, and so forth. The scientific knowledge and accurate control of the distribution and the microstructure of the guest species in the interlayer are critical issues. Such advanced clay-based materials obtained by preparation through designed species within interlayers have provided promising applicability in a number of catalytic reactions such as oxidation, dehydration, hydrogenation, cracking, isomerization, and alkylation. Several key problems and prospects are also remarked.

Key words: smectite, layered structure, ion exchange, nanocomposite, catalytic material