Synthesis of hierarchical Bi2O3/Bi4Ti3O12 p–n junction nanoribbons on carbon fibers from (001) facet dominated TiO2 nanosheets

Abstract

A novel hierarchical photocatalyst of Bi₂O₃/Bi₄Ti₃O₁₂ p–n junction nanoribbons (NRs) on carbon fibers has been successfully fabricated from the precursor of (001) facet dominated TiO₂ nanosheets (NSs), which provide well-shaped templates. The dominant (001) facets of the TiO₂ precursor diminished slower than the (101) facets during the hydrothermal process. Single crystallized p-type Bi₂O₃ and n-type Bi₄Ti₃O₁₂ coexist, forming p–n junctions within one NR. This hierarchical nanostructure exhibits markedly improved photocatalytic activity for degradation of methyl orange. The improvement can be attributed to enhanced absorption in the visible light region due to the ultrathin NRs, more efficient charge separation/transportation owing to the formation of a p–n junction, and high exposure of reactive (001) facets resulting from the formation of a hierarchical structure. Moreover, this hierarchical photocatalyst shows high stability and excellent recycling properties.