Photocatalytic decomposition of nitrogen oxides over TiO2 coatings elaborated by liquidfeedstock plasma spraying

摘要

In this paper, the modified method of plasma spraying using liquid suspension feedstock was used to elaborate thintitanium dioxide coatings. TiO2 Degussa P25 powder were dispersed by continuous stirring in distilled water andalcoholic solutions and injected in an Ar-H2 or Ar-H2-He plasma plume under atmospheric conditions. Scanningelectron microscopy and X-ray diffraction were performed to study the microstructure and crystalline phases oftitanium dioxide coatings. The anatase content in the elaborated TiO2 deposits strongly depended on the type ofthe suspension solvent. The photocatalytic activity of the titanium dioxide coatings was evaluated from theconversion rate of nitrogen oxides and compared with that of the initial powder. The obtained results allowed toaffirm that the method of the liquid plasma spraying proved to be a promising technique to elaborate photocatalyticTiO2 coatings for the removal of nitrogen oxides pollutants.