Photocatalytic performance of plasma sprayed Pt-modified TiO2 coatings under visible light irradiation

Plasma sprayed Pt/TiO2 coatings were prepared by Atmospheric Plasma Spraying process. As-sprayed coatings were characterized by TEM, XRD and XPS. The photocatalytic performance was evaluated through the photo mineralization of methylene blue. All the Pt modified titanium dioxide coatings show significant absorption in the visible light range, while the pure titania coating reflects almost all the visible light. The photocatalytic efficiencies of as-sprayed pure TiO2 coating and Pt/TiO2 coatings are almost same under the irradiation of visible light. However, the efficiencies of all Pt/TiO2 coating are greatly improved comparing with that of pure TiO2 coating by applying 15 V external bias under the irradiation of visible light.