Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation

Iodine doped tin oxide (SnO₂:I) nanoparticles were prepared by sol-gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO₂:I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO₂nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO₂nanoparticles under similar illumination conditions.