Fabrication of Cu2O/TiO2 nanotube heterojunction arrays and investigation of its photoelectrochemical behavior

Cu2O/TiO2 nanotube heterojunction arrays have been prepared by photoreduction depositing Cu2O nanoparticles on TiO2 nanotube arrays. The heterojunction arrays show uniformly distributed Cu2O nanoparticles, and high crystallinity of anatase and cubic from the TiO2 and Cu2O, respectively. The asymmetry of the current-voltage plot for the material reveals that a heterojunction has been formed between TiO2 and Cu2O. Enhanced charge separation efficiency and improved photoconversion capability are confirmed by electrochemical impedance spectroscopy and photocurrent measurement. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3224181]