Degradation of Methyl Orange and Congo Red dyes by using TiO 2 nanoparticles activated by the solar and the solar-like radiation

In this study we used TiO2 nanoparticles as semiconductor photocatalysts for the degradation of Methyl Orange (MO) and Congo Red (CR) dyes in an aqueous solution. Since TiO2 particles become photocatalytically active by UV radiation, two sources of UV-A radiation were used – natural solar radiation which contains 3–5% UV-A and artificial, solar-like radiation, created by using a lamp.