Hybrid oxide nanostructures as photocatalysts

Abstract

The photocatalytic process and various approaches to enhance the efficiency of photocatalysis in metal oxides nanostructures are described in this chapter. The concept of coupling nanostructured metal oxide to another metal oxide or noble metal nanoparticles (NPs) to form hybrid material with novel properties is an attractive and efficient approach for enhancing the photocatalytic efficiency. The hybrid photocatalysts have shown to improve the carrier separation and visible light absorption and thus the photocatalytic efficiency. The effect of various noble metal NPs (Pt, Au, Ag) decoration/coupling on the photocatalytic activity of the metal oxide (TiO2, ZnO) semiconductors is discussed with the possible mechanisms. Various hybrid oxide nanostructures such as TiO2–ZnO, TiO2–SnO2–TiO2–WO3, TiO2–SiO2, ZnO–Fe2O3, ZnO–Fe3O4, ZnO–SnO2, ZnO–Cu2O are discussed for their photocatalytic activities. The promising photocatalytic properties of metal oxides hybrid with carbon based materials like carbon nanotubes and graphene is also described.