Shape-controlled synthesis of BiVO4 hierarchical structures with unique natural-sunlight-driven photocatalytic activity

A detailed study on the shape control of bismuth vanadate (BiVO4) hierarchical structures and on their corresponding natural sunlight-driven photocatalytic activities was performed. We have developed a time-saving, cost-effective, surfactant-free approach for the controlled synthesis of uniform monoclinic scheelite BiVO4 hierarchical structures, obtaining diverse BiVO4 architectures including peanuts, dumbbells, flowers, spheres, olives, and rod-sheaves, via facile pH-dictated solvothermal routes with the aid of either NH3·H2O or NaOH. The influences of the morphologies of the synthesized BiVO4 hierarchical structures on the photocatalytic degradation of Rhodamine B (RhB) have been investigated, indicating that the enhanced photocatalytic performances were neither related to the surface area values nor the aspect ratios of the fabricated photocatalysts, but associated with the unique shaped configurations produced under specific low temperature hydrothermal conditions. The effects of the active species involved in the photocatalytic process and the cycle-stability of the prepared BiVO4 photocatalysts have also been examined.