Abstract: Clay minerals of the smectite group are widely applied in fields such as civil engineering, environmental science, cosmetics, and coatings, owing to their excellent ion-exchange capability and swelling properties. In recent years, they have also attracted growing interest as advanced functional materials. Our research group is particularly focused on the design of light-responsive materials based on smectite.1,2) Because many smectites contain transition metals such as iron within their structures, discussions have centered on issues including the material’s whiteness and the quenching of photoexcited states of dyes adsorbed via iron ions.3) Recently, we have obtained high-whiteness raw smectite minerals suitable for cosmetic and other color related applications, and have reported several developments,4) the synthesis of organoclays modified with surfactants the design of polymer nanocomposites exhibiting mechanochemical photoluminescence,5-7) utilizing their whiteness, particle size, and surface charge density; and the creation of novel pillared clays employing plant-derived compounds.8) In addition, we have found that iron-rich bentonite can serve as a photocatalyst for water reduction.9) This presentation introduces our recent advances in the exploration and design of such innovative clay-based materials.
References
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