Designed air purifier reactor for photocatalytic degradation of CO2 and NO2 gases using MWCNT/TiO2 thin films under visible light irradiation

Abstract

The air purifier reactor was designed and fabricated to develop the photocatalytic treatment of CO2 and NO2 gases under visible light irradiation based on multi-walled carbon nanotubes/titanium dioxide (MWCNT/TiO2) thin films. MWCNT/TiO2 thin films were synthesized by a simple dip-coating method on the glass substrate. Structural properties were characterized by SEM, EDX, XRD and optical properties by UV–Vis absorption spectroscopy. The XRD patterns showed the presence of anatase phase. The absorption spectrum of MWCNT/TiO2 revealed a redshift in the optical absorption edge due to carbon doping. For the first time, to evaluate the visible light photocatalytic activity, concentration reduction of CO2 and NO2 gases were measured by Ion Mobility Spectrometry(IMS) analyzer. The designed reactor indicated a high visible light photocatalytic activity for CO2 and NO2 degradation. The calculation of the Photocatalytic reaction by the Langmuir-Hinshelwood model showed that it followed the pseudo-first-order rate law.