Effect of TiO₂ thin film thickness on NO and SO₂ removals by dielectric barrier discharge-photocatalyst hybrid process

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.