日本ゼオライト学会　刊行物 Publication of Japan Zeolite Association

The preparation and characterization of highly active photocatalysts and their environmental applications and the excited state chemistry of the guest molecules included within restricted cavites of zeolite and mesoporous silica have been reviewed. The design of molecular and/or cluster size photocatalysts prepared within the cavities of zeolites is of great interest because of their fascinating physical and chemical properties, unusual internal surface topology, and ion-exchange capacities. The unprecedented application of the anchoring techniques and the use of zeolites as supports can be considered an innovative breakthrough in the preparation of highly dispersed photocatalysts which exhibit unique and remarkable photocatalytic properties. Furthermore, zeolites are considered to be one of the most suitable materials to investigate a variety of host-guest interactions and their role in the photochemical nature of the guest molecules. The distinct and basic properties of zeolites, i.e., the micro-polarity and polarizability of the zeolite interior due to the type of cations and the size of the channels and cages has led to dramatic changes and modifications in the electronic states and molecular motion as well as the photochemical reactivity of molecules within the zeolites.