Influence of Ultraviolet Light on Photocatalytic TiO2 Materials

• Published in: Journal of materials in civil engineering 2013-07, Vol.25 (7), p.893-898
• Main Authors: Hanson, Shannon, Tikalsky, Paul
• Format: Article
• Language: English
• Subjects: Air pollution; Efficiency; Irradiance; Ozone; Photocatalysis; Pollutants; Technical Papers; Titanium dioxide; Ultraviolet
• ISSN: 0899-1561; 1943-5533
• DOI: 10.1061/(ASCE)MT.1943-5533.0000715

AbstractNOx gases affect the diurnal rise and fall of tropospheric ozone. By removing NOx gases through the use of titanium dioxide (TiO2) photocatalytic materials, tropospheric ozone concentrations could be reduced. Recent developments related to the photocatalytic pollution reduction capabilities of TiO2 have led a movement to understand the material properties required to create construction materials which have the potential to reduce NOx air pollutants. A research program was undertaken to isolate variables that impact the kinetics of TiO2 reaction. Six TiO2 materials were tested for NOx removal efficiencies. The productive TiO2 materials were then tested at multiple concentrations to determine the effect of ultraviolet (UV) irradiance on their efficiency to reduce NOx air pollutants. It was found that specific anatase TiO2 phases manufactured and sized to have high levels of photocatalytic activity could reduce NOx air pollutants at high efficiencies. The NOx removal efficiency was 2.4 times higher at a UV irradiance of 1,300  μW/cm2 than at 150  μW/cm2, equivalent to a sunny or shady surface, respectively.