Hierarchical SrTiO ₃/TiO ₂ nanofibers heterostructures with high efficiency in photocatalytic H ₂ generation

Through hydrothermally growing SrTiO ₃ cubics on the surface of electrospun TiO ₂ nanofibers, SrTiO ₃/TiO ₂ nanofibers heterostructures were successfully fabricated in the present study. This process is able to ensure uniform distribution of SrTiO ₃ on the surface of TiO ₂ nanofibers and lead to close contact between SrTiO ₃ and TiO ₂, which is beneficial for the fast separation of photogenerated electrons and holes so as to suppress the recombination of photogenerated electrons and holes at the interphase of SrTiO ₃ and TiO ₂. Besides this, the long 1D fibrous structure easy for electron transfer, the hierarchical structure promoting mass transfer and allowing more light reflection and absorption, and the large specific surface area providing more reactions sites to facilitate the reactants to desired oxidation places all together create a synergistic effect on improving the photocatalytic activity of the hierarchical SrTiO ₃/TiO ₂ nanofibers heterostructures. Under the irradiation of UV light, in a water/methanol sacrificial reagent system, the SrTiO ₃/TiO ₂ nanofibers heterostructures generate five times more H ₂ than bare TiO ₂ nanofibers because of its high photocatalytic activity.