Iranian Journal of

Background and Objective: Formaldehyde is a toxic volatile organic compound, which its removal from polluted air is essential. One of the techniques available for removing such compounds is photocatalytic degradation. The aim of this study was to investigate the photocatalytic degradation of gaseous formaldehyde on TiO₂ nanoparticles coated on reduced graphene oxide

Materials and Methods: The synthesized reduced graphene oxide- TiO₂ nanocomposite was characterized using SEM, EDS, and FTIR spectra. The photocatalytic activity of prepared reduced graphene oxide- TiO₂ nanocomposite was investigated for degradation of gaseous toluene under different operational conditions such as different initial concentration, flow rate, and time.

Results: The photocatalytic degradation efficiency of the RGO-TiO₂ nanocomposite was much higher than P25 TiO₂. The photocatalytic degradation efficiency of the RGO-TiO₂ nanocomposite decreased by increasing the flow rate so the flow rate is a key factor for the use of RGO-TiO₂ nanocomposite as a photocatalyst. The results showed that the photocatalytic degradation rates decreased from 89 to 30% with increasing formaldehyde initial concentration from 0.1 to 1 ppm.

Conclusion: This research indicated that RGO-TiO₂ nanocomposite can be effectively used as suitable photocatalyst to remove gaseous pollutants. One of the advantages of the as-prepared composite was using visible light instead of UV to activate the oxidation process.