Thermal Decomposition Fabrication of Fe₂O₃ Nanoparticle-Sensitized TiO₂ Nanotube Arrays and Their Photoelectrochemical Properties

TiO₂ nanotube arrays/Fe₂O₃ nanoparticles (TiO₂ NTs/Fe₂O₃) with enhanced visible-light activity were synthesized by a two-step approach including an electrochemical anodization technique followed by a thermal decomposition approach. The structural investigation indicated that Fe₂O₃ nanoparticles grew uniformly on the walls of TiO₂ nanotubes. The Fe₂O₃ modification of TiO₂ NTs resulted in an increase in the visible light adsorption, and the increases in photocurrent and photocatalytic efficiency were dependent on the thermal decomposition times. The enhanced photoelectrochemical properties of TiO₂ NTs/Fe₂O₃ could be attributed to the improvement of charge separation derived from the coupling effect of TiO₂ NTs and Fe₂O₃ nanocomposite.