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

Porous materials such as mesoporous silicas and zeolites provide well-ordered pore voids of uniform size. These minute pore spaces are comparable with various kinds of molecules in size, and consequently dominate the diffusion and the transport of the molecules in their pore voids. In the cases of mesoporous materials, the modifications of the outlet of their pores with responsive organic substituents as openable and closable gates manipulate the release and the transport of various molecules between inside and outside of the pore voids. These effects are applied to controlled release of molecules such as steroids and switching of the progress of catalytic reaction. Furthermore, the molecular motion of azobenzene substituent caused by the continuous photo isomerization between its trans and cis isomers promotes the release of molecules from the pore. On the other hand, the micropores of zeolites were sealed by the graftings of organosilane and organoboron compounds on their surfaces, and the permeation of molecular nitrogen into the micropores was completely restricted. After calcination or acid treatment, the micropore of zeolites was reopened, and the nitrogen permeation recovered.