Heterostructure of epitaxial (001) Bi4Ti3O12 growth on (001) TiO2 for enhancing photocatalytic activity.

In this work, specific exposed crystal facets were employed to construct epitaxial heterostructure for high efficiency carriers transmission channel. The (001) face of anatase TiO 2 was chosen to composite (001) Bi 4 Ti 3 O 12 for two reasons. First, as the lattice spacing of (110) faces of anatase TiO 2 (0.26741 nm) is very close to that of (020) (0.27240 nm) or (200) (0.27080 nm) faces of Bi 4 Ti 3 O 12 , (001) Bi 4 Ti 3 O 12 will epitaxial grow on the (001) faces of anatase TiO 2 . Second, due to the high surface energy, the chemical reaction between TiO 2 and Bi(NO 3 ) 3 will occur at a low Bi:Ti mole ratio to form well crystallographic Bi 4 Ti 3 O 12 nanocrystals. Compared with Bi 4 Ti 3 O 12 /P25 composite, this epitaxial heterostructure is confirmed to be an ideal carriers exchange channel to extend the separation time of photo-induced carriers and enhance photocatalytic activity. This study demonstrates the importance of crystal facets choice of substrate for constructing high efficiency carriers transmission channel. [ABSTRACT FROM AUTHOR]