ZnO nanoparticles have been successfully synthesized by a facile precipitation procedure by mixing aqueous solutions of Zn(II) acetate and dissolved NaCO at pH ca. 7.0 without template addition. We have investigated the effect of annealing temperature in the final surface and structural properties. Photocatalytic studies were performed using two selected substrates, Methyl Orange and Phenol, both as single model substrates and in mixtures of them. It has been stated that calcination treatments lead to a significant improvement in the photocatalytic properties of the studied samples, even better than TiO(P25). As expected, the addition of Ag during the photocatalytic degradation of MO increases the reaction rate of the degradation of MO, giving a resultant Ag/ZnO photocatalyst which, after recovery, can be reused at least 18 times for the MO degradation tests, being even more photoactive than ZnO.

This work was supported by research fund from Project Ref. CTQ2015-64664-C2-2-P(MINECO/FEDER, EU). XPS and others research services of SITIUS University of Seville are also acknowledged.