Silica-pillar formation mechanism in layer structured manganese titanate

The layer structured manganese titanate, RbxMnxTi2-xO(4) (x = 0.75) was pil lared with decylammonium ions by the ion-exchange, and then, tetraethyl ort hosilicate (TEOS) was hydrolyzed between pillared layers. On calcination, t he alkylammonium ions were decomposed, and the hydrolyzed TEOS was in turn changed into silica pillars, forming micropores between the layers. The amo unt of silica formed was dependent on the amount of water contained in the decylammonium pillared titanates. The specific surface area of the silica-p illared structure increased linearly with the increase of the basal spacing and the amount of silica introduced. This suggested that the interlayer sp ace was filled with silica particles of nano- or subnano-meter sizes, which were packed in a uniform way irrespective of the basal spacing. The microp ores were formed between the packed silica particles.