Platinum 1,10-phenanthroline: Photosensitizer for photocatalytic degradation of 4-chlorophenol

Abstract

It is more economic to apply photodegradation of organic pollutants in presence of the visible light irradiation (sunlight) than applying more costfull ultraviolet lamps. Hence, platinum 1,10-phenanthroline complex has been prepared and tested as a photosensitizer for photodegrading 4-chlorophenol in water, which has been found almost completely achieved (98.5 %) after three hours of visible irradiation. Nevertheless, irradiation at 364 and 254 nm exhibits lower efficiencies. At visible irradiation, the platinum complex gives the highest activation of singlet state oxygen formation (¹O₂) compared to 364 and 254 nm irradiation as supported by electron para-magnetic resonance data. On the other hand, the behavior of formation and disappearance of photodegradation intermediates: hydroquinone, benzoquinone, hydroxybenzoquinone, using the platinum complex applying the three current irradiations are found to supports these findings. However, organic acids have accumulated as a function of irradiation time and hence considered to be rate-controlling.