CdS and ZnS mixtures, Fe 2 O 3 and TiO 2 pillars were constructed in the interlayer of montmorillonite, layered double hydroxide, H 4 Nb 6 O 1 7 and H 2 Ti 4 O 9 by the intercalation reactions. The thicknesses of the semiconductors incorporated were less than 1 nm and the band gap energies of them were slightly larger than those of normal crystalline ones. The photocatalytic activities of the semiconductors incorporated were superior to those of unsupported ones. The incorporation of semiconductors in the interlayers of semiconducting layered compounds such as H 2 Ti 4 O 9 and H 4 Nb 6 O 1 7 was much more efficient in enhancing the hydrogen production activity than when an insulator such as montmorillonite and layered double hydroxide was used, since the recombination of photo-induced electrons and holes was depressed by the electron transfer from the incorporated semiconductors to the semiconducting host layer.