Cu2O-Decorated TiO2 Nanotubes with Enhanced Optical Properties and Photocatalytic Performance

Cu2O-decorated TiO2 nanotube arrays (NTAs) are obtained using a two-step approach on Ti sheets. The applied voltage of Cu2O is − 0.2 V and − 0.3 V, respectively. The morphology and structure of these samples have been studied by field-emission scanning electron microscope (FESEM) and an x-ray diffractometer (XRD). FESEM analyses show that nanometre-sized Cu2O particles are attached to the TiO2 NTAs and the quantity of the Cu2O has greatly increased when the applied voltage tends to be more cathodic. The diffraction peaks for the anatase TiO2 and Cu2O are detected from XRD analysis. The bandgaps of TiO2 NTAs shift from 3.27 eV to 3.11 eV based on UV–Vis absorption spectra measurements. The photocatalytic performance of the Cu2O-TiO2 NTAs depends on the Cu2O deposition voltage.