Photocatalytic and photoelectrocatalytic performance of sonochemically synthesized Cu2O@TiO2 heterojunction nanocomposites.

Cu2O@TiO2 heterojunction nanocomposites were prepared via ultrasonic method towards the removal of the environmental pollutant of MO by the visible light photocatalytic approach. The structure of prepared Cu2O@TiO2 heterojunction nanocomposites was analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscope, photoluminescence spectroscopy, UV-Visible absorption spectroscopy, diffused reflectance spectroscopy. The photocatalytic degradation ability was tested using methyl orange as a model pollutant. From the observed pseudo-first order reaction, it was clear that Cu2O@TiO2 nanocomposites showed enhanced photocatalytic activity (rate = 0.223 s-1). The formation of demethylated methyl orange as an intermediate was identified from HPLC analysis at a retention time of 3.47 min. When doped with Cu2O, the TiO2 preserved the integrity of its structural, revealing the morphology there is no significant changes have been made, favoring photoelectrochemical appliances. In presence of illumination, the photocurrent of Cu2O@TiO2 was 4.5 folds greater than that of TiO2, involving that incorporating with Cu2O extensively enhanced mobility of electron via reducing the recombination rate of electron-hole pairs.