Phenol-photodegradation on ZrO2. Enhancement by semiconductors

On illumination with light of wavelength 365 nm phenol undergoes degradation on the surface of ZrO2. The rate of degradation enhances linearly with the concentration of phenol and also the light intensity but decreases with increase of pH. The photonic efficiency of degradation is higher with illumination at 254 nm than with 365 nm. The diffuse reflectance spectral study suggests phenol-sensitized activation of ZrO2 with 365 nm light. TiO2, Fe2O3, CuO, ZnO, ZnS, Nb2O5 and CdO particles enhance the photodegradation on ZrO2, indicating inter-particle charge-transfer. Determination of size of the particles under suspension, by light scattering technique, shows agglomeration of particles supporting the proposition of charge-transfer between particles.

Figure optionsDownload as PowerPoint slideHighlights
► Phenol-adsorbed ZrO2 absorbs UV-A light.
► Phenol degradation on ZrO2 is larger with UV-C light than with UV-A light.
► Particulate semiconductors enhance phenol photodegradation on ZrO2 particles.
► Particles agglomerate.