ION-EXCHANGEABLE LAYERED NIOBATES AS PHOTOCATALYSTS

Silica pillared-niobates were prepared from a, so called, layered pero vskite, KCa2Nb3O10, by using alkylammonium ions as swelling reagents. A product with the interlayer spacing expanded by ca. 1.2 nm and the B ET surface area of ca. 200 m2/g was obtained when an octylammonium int ercalated precursor was used. The photocatalytic activities of these s ilica pillared-niobates were compared with those of the original KCa2N b3O10 and the proton-exchanged derivative. It was revealed that silica pillared-niobates showed a high and characteristic photocatalytic act ivity.