A facile template-free synthesis of Bi2Sn2O7 with flower-like hierarchical architecture for enhanced visible-light photocatalytic activity

Bi2Sn2O7 with flower-like hierarchical architecture was successfully synthesized via a facile template-free hydrothermal method. The structure–property relationships of such unique structured Bi2Sn2O7 were studied. The results show that the 3D flower-like Bi2Sn2O7 hierarchical architecture is composed of 2D Bi2Sn2O7 nanosheets, which increases the specific surface area of Bi2Sn2O7, which is about four times that of Bi2Sn2O7 nanoparticles. Meanwhile, 2D nanosheets result in an effective separation of photo-generated carries, and the average carrier lifetime of flower-like Bi2Sn2O7 is 3.26 ns, which is longer than that of Bi2Sn2O7 nanoparticles (1.88 ns). Therefore, the flower-like Bi2Sn2O7 displays excellent photocatalytic activity for degrading tetracycline hydrochloride compared with Bi2Sn2O7 nanoparticles. The active species trapping test confirmed that h+ and ˙O2− are dominant reactive species in the photocatalytic reaction. Moreover, this novel structure can also integrate the advantages of nano-sized materials with high surface area and micro-sized materials with good dispersion, exhibiting excellent properties of high photocatalytic activity, easy recyclability and good catalytic stability.