Screen-printing of TiO2 photocatalytic layers on glazed ceramic tiles

In this work TiO2 layers have been deposited by screen-printing in common glazed ceramic tiles. These TiO2 layers were evaluated for the photocatalytic degradation of Orange II in aqueous solutions, in a batch photoreactor under visible light, and compared with TiO2 (anatase) suspensions. The photocatalytic behaviour of the TiO2 was evaluated by taking into account experimental variables which include (i) firing temperature of the TiO2 printed layer; (ii) layer thickness; (iii) operation time. Optimal processed layers showed an interesting decolourisation performance (over 90% efficiency after 7–8 h). The maximum decolourisation rate, assuming an apparent first order reaction, is over 0.050 min−1 and is close to values reported in the literature for supported TiO2 photocatalysis under UV irradiation. We anticipate that these new ceramic materials might be developed as an interesting alternative to TiO2 suspensions, for example in photocatalytic applications excusing the removal of the particles at the end of the process.