Comparison of SFS, SPS and HVSFS for the Production of Photocatalytic Titania Coatings Available to Purchase

This study assesses the viability of three suspension spray processes for producing photocatalytic TiO₂. In the experiments, flame, plasma, and HVOF torches were used to spray TiO₂ suspensions onto stainless steel substrates, varying process parameters in order to gauge their effect on phase composition, crystal size and, in turn, photoactivity. The TiO₂ samples were characterized by means of XRD, SEM, and UV-Vis analysis and photocatalytic hydrogen-production testing. Suspension flame spraying proved to be the most effective method, producing phase-controlled nanostructured titania 32% more photoactive than the SPS samples and up to five times more active than analogous coatings produced by CVD.