Preparation of Silica Pillared Ca₂Nb₃O₁₀ and Its Photocatalytic Activity

Silica pillared Ca 2 Nb 3 O 10 was prepared from the layered perovskite KCa 2 Nb 3 O 10 via alkylammonium ion intercalated Ca 2 Nb 3 O 10 . The obtained materials were characterized by XRD, TEM, NMR, and BET measurements. The interlayer spacing increased in parallel with the length of the alkyl chain of intercalated alkylamines although the BET surface area was not reflected in this increase. The photocatalytic activity of the silica pillared Ca 2 Nb 3 O 10 was studied for H 2 evolution from aqueous alcohol solutions. Marked increase by ca. 30 times in activity was obtained for silica pillared Ca 2 Nb 3 O 10 compared with the original HCa 2 Nb 3 O 10 in an aqueous propanol or butanol solution, while no difference was observed in an aqueous methanol solution. The result was interpreted in terms of the intercalation of the reactant alcohol molecules into the interlayer space.