Effect of TiO₂ Thin Film Thickness on NO and SO₂ Removals by Dielectric Barrier Discharge-Photocatalyst Hybrid Process

Abstract

We coated the glass beads with TiO2 thin films by a rotating cylindrical plasma chemical vapor deposition (PCVD) reactor and applied the TiO2–coated glass beads to remove NO and SO2 in a dielectric barrier discharge-photocatalyst hybrid (DBD-PH) process. The thickness of TiO2 thin films on glass beads was controlled precisely by changing the deposition time. The UV light generated from the plasma discharge in DBD-PH process activates the TiO2 photocatalyst on glass beads and the NO and SO2 removal efficiency are removed more easily by the reactive radicals generated from plasma reactions and TiO2 photocatalyst. We found the optimum thickness of TiO2 thin film on glass beads was about 600 nm to remove NO and SO2 by the DBD-PH process. The NO and SO2 removal efficiencies increase as applied peak voltage, residence time or pulsed frequency increases or as initial NO and SO2 concentration decreases.