Controllable synthesis and efficient photocatalytic activity of BiOF nanodisks exposed with {101} facets, instead of {001} facets

Abstract So far, BiOF nanodisks exposed with {101} facets have not been reported. In this work, BiOF mainly exposed with {101} facets, instead of common {001} facets, are synthesized at different pH values via a simple hydrothermal method. It is interesting that BiOF thick rectangular plates and thin round nanodisks are formed through the growth preferential along [001] and [101] directions, respectively. On the base of layered crystallography structure, the preferential growth along [001] direction favors to form a thick multi-layered structure, whereas [101] direction for a thin fewer-layered structure. Moreover, more surface oxygen vacancies are contained in thin nanodisks, which reduces the band gap and improves charge transfer and separation. As a result, BiOF round nanodisks show an activity 7.9 times higher than rectangular plates for the degradation of rhodamine B (RhB) under ultraviolet light irradiation (λ ≤ 400 nm).