Facile Fabrication of Heterostructured Bi2O3-ZnO Photocatalyst and Its Enhanced Photocatalytic Activity

The development of coupled semiconductor photocatalysts makes a significant advancement in catalytic functional materials. A new heterostructured Bi2O3-ZnO, synthesized by a simple hydrothermal-thermal decomposition method, exhibited higher photocatalytic activity for the degradation of Acid Black 1 (AB 1) under UV light than pure ZnO, Bi2O3, and commercial Degussa P25. X-ray powder diffraction analysis reveals that the as-synthesized product has the monoclinic lattice phase of Bi2O3 and the hexagonal wurtzite phase of ZnO. HR-SEM images show that Bi2O3-ZnO has an ordered mixture of nanofiber and nanochain structures. This heterostructured Bi2O3-ZnO has increased UV absorption when compared with ZnO. The enhanced photocatalytic activity of Bi2O3-ZnO is attributed to the low recombination rates of photoinduced electron-hole pairs, caused by the vectorial transfer of electrons and holes between ZnO and Bi2O3. Higher efficiency at neutral pH 7 and reusability in the degradation of AB 1 makes Bi2O3-ZnO, a promising candidate for the photocatalytic treatment of dye effluent.