Efficient Photocatalytic Activity of PZT/TiO2 Heterojunction under Visible Light Irradiation

A Pb(Zr0.52Ti0.48)O-3/TiO2 composite photocatalyst with nanostructured heterojunction was prepared by a simple sol-gel method. The catalyst was characterized by powder X-ray diffraction, nitrogen adsorption-desorption, transmission electron microscopy, UV-vis diffuse reflectance spectroscopy, electrochemistry technology, and spin-trapping electron paramagnetic resonance. The visible light-induced photocatalytic activities were evaluated by decomposing ethylene in gas phase. The result showed that the prepared composite catalyst exhibited efficient photocatalytic activities with high photochemical stability under visible light irradiation. Moreover, it also showed excellent photocatalytic performance under UV light or simulated sunlight irradiation. On the basis of the measurement of flatband potentials of the samples and the detection of active oxygen species (such as O-2(center dot-) and OH center dot), a visible light-induced photocatalytic degradation mechanism of ethylene on PZT/TiO2 was proposed.