3D Bi₂WO₆/TiO₂ Hierarchical Heterostructure: Controllable Synthesis and Enhanced Visible Photocatalytic Degradation Performances

A three-dimensional (3D) multicomponent oxide, Bi 2 WO 6 /TiO 2 as an example, hierarchical heterostructure was successfully synthesized as a mat via a simple and practical electrospinning-assisted route. The as-prepared hierarchical nanofibrous mat consisted of Bi 2 WO 6 nanoplates growing aslant on the primary TiO 2 nanofibers. Interestingly, the nanoplates were further composed of nanoparticles with a size of less than 20 nm. Bi 2 WO 6 with different morphologies and microstructures could be obtained by adjusting the concentration of the precursor. From the mat (10 cm) to the nanoparticle (20 nm), this multicomponent oxide mat due to the self-supporting property could be layed or hung conveniently anywhere under solar irradiation and recycled easily. Due to the structure−property relationships, the 3D Bi 2 WO 6 /TiO 2 hierarchical heterostructure exhibited enhanced visible photocatalytic activity over that of the bulk Bi 2 WO 6 /TiO 2 powder (SSR), the Bi 2 WO 6 nanoparticles (BWO), and the TiO 2 sample in the decomposition of both acetaldehyde (CH 3 CHO) in air and rhodamine B (RhB) in water which are typical model pollutants. Close investigation revealed that the surface area, grain size, and hierarchical heterostructure of the as-prepared Bi 2 WO 6 /TiO 2 mat could improve the photocatalytic activities.