Hydrothermal synthesis of BiVO4 square tubes using BiOIO3 nanosheets as self-sacrificing agents and their photoelectric properties

Large-scale synthesis of BiVO4 square tubes has been achieved through hydrothermal method by using BiOIO3 nanosheets as self-sacrificing agents. XRD, SEM and TEM analysis indicated the transformation of original orthorhombic BiOIO3 nanosheets to the monoclinic BiVO4 square tubes. EDS also confirmed the formation of BiVO4 after hydrothermal treatment. The evolution process was elucidated with a dissolution-recrystallization-induced concentration depletion mechanism. The materials obtained at different stage of reaction exhibited a red-shift absorption edge, and the repeatable photoresponse with light pulsation. PL spectra proved the restrained exciton recombination in composites, and the charge carriers transfer mechanism was discussed.