Plasma sprayed TiO2: The influence of power of an electric supply on relations among stoichiometry, surface state and photocatalytic decomposition of acetone

The influence of input power on plasma sprayed coating was studied for a water-stabilized plasma spray torch (WSP®) and ceramic coatings formed from titanium dioxide (TiO2). All other spray setup parameters were secured during the experiment with electric supply power as the only variable factor. Physical characteristics of the coatings were tested by means of Raman spectroscopy and X-ray photoelectron spectroscopy which are able to determine the stoichiometry and surface chemical composition of the coatings. Further, stoichiometry and surface states are crucial for the photocatalytic efficiency of the coatings. The photocatalytic procedure involved was UV-induced decomposition of acetone. Links between the tested features are drawn. The lower supply power used during the spraying of TiO2 coating resulted in higher activity with respect to the photocatalytic point of view. Both the stoichiometry and surface composition are in the same time deviated from pure TiO2.