Morphology control of the nanoporous nickel phosphate VSB-5 from large crystals to nanocrystals

The nanoporous nickel phosphate, VSB-5 has been synthesized with organic amines in various conditions. The VSB-5 was synthesized only in weakly basic conditions. Among various factors used for synthesis, the pH of the reactant mixture was shown to be a decisive factor to form the nickel phosphate VSB-5. However, a type of organic amine used as a base was important for the control of crystal size and shape. Large crystals with a size of about 200 μm in length have been obtained by using tri-n-propylamine in a highly diluted condition, whereas nanocrystals with a size of 20 nm in width and 200 nm in length have been formed in the presence of 1,6-diaminohexane.