Notice of Retraction: Effects of inorganic anions on TiO2 photocatalytic degradation of phenol

Abstract

The effects of various inorganic anions (SO42-, NO3-, H2PO4-, HCO3-, CO32-, F-, Cl-, Br- and I-) on the photocatalytic degradation of phenol were investigated under UV light irradiation. In present work, low initial pH value in the presence of H2PO4- increased the photocatalytic degradation efficiency of TiO2, high initial pH value in the presence of HCO3-, CO32- and F- decreased the photocatalytic degradation efficiency of TiO2, and no change of initial pH value in the presence of SO42- and NO3- had little effect on the photocatalytic degradation efficiency of TiO2. The results indicated that the effects of the inorganic anions on the photocatalytic degradation of phenol depended strongly on the pH, which was related with the adsorption of phenol on the surface of TiO2. No significant relationship between the initial pH and the photocatalytic degradation efficiency of TiO2 was observed in the experiment with the addition of Cl-, Br- or I-, indicating that inorganic anions inhibited the photocatalytic degradation efficiency of TiO2 by their trapping hydroxyl radicals (OH·).