Enhanced visible light photocatalysis of TiO2 by Co-modification with Eu and Au nanoparticles

TiO2 photocatalysis has been studied widely in environment protection and energy generation applications. But, the intrinsic absence of visible light response and the high recombination rate of photo-generated charge carriers significantly limited the efficiency of photocatalysis with TiO2 materials. Herein, a facile approach was constructed to develop visible-light-induced TiO2 photocatalysis by co-modification with Eu and Au nanoparticles. The synthesized Au/Eu-TiO2 material was characterized by XRD, SEM, TEM, DRS, XPS, and N-2 adsorption measurements. Visible light catalytic performance of the Au/Eu-TiO2 catalyst was evaluated by using the photodegradation of RhB as a model reaction. It was shown that this Au/Eu-TiO2 exhibited a better photocatalytic activity than the single Au modified TiO2 (Au/TiO2) or the single Eu modified TiO2 catalyst (Eu/TiO2), and also exhibited a good reusability for the targeted reaction. This remarkably improved performance of Au/EuTiO2 could be attributed to the synergetic effect of Eu and Au co-decoration, which not only enhanced visible light absorption but also promoted charge carriers transfers as evidenced by DRS, XPS and transient photo-current spectra. Moreover, a possible reaction mechanism for the Au/Eu-TiO2 photocatalysis was proposed.