Titanate nanotubes as ethanol decomposition catalysts: Effect of coupling photocatalysis with non-thermal plasma

Titanate nanotubes were synthesized by hydrothermal treatment of TiO2 in an alkaline aqueous solution followed by acid washing and calcination at 400 degrees C. The prepared nanotubes were characterized by XRD, N-2-physisorption and photoluminescence. The initial titanium dioxide and titanate nanotubes were both used to remove the ethanol, at low concentration, under UV light and under non-thermal plasma. The combination of those both technologies was also tested. The influence of the initial ethanol concentration and the plasma input power were also evaluated. Compared to the initial titanium dioxide (P25), the nanotubes enhance significantly the oxidation of ethanol in air. This effectiveness is greatly enhanced when the non-thermal plasma and UV are coupled. This behavior may be related to the surface and optical proprieties of titanate nanotubes. A kinetic simulation of ethanol conversion has shown that the behavior observed when photocatalysis and non-thermal plasma are coupled could result from additive ethanol elimination by photocatalysis alone and plasma-catalysis alone. This observation implies that titanate nanotubes are able to activate ozone produced by plasma without external UV irradiation. (C) 2017 Elsevier B.V. All rights reserved.