Comparative study of the photocatalytic decolorization of rhodamine B dye by AgI-Ag3PO4 prepared from co-precipitation and ion-exchange methods

AgI in the sample could adsorb RhB and also induce it to degrade through the N-deethylation process, leading the hypsochromic shift of maximum absorption band with increasing the irradiation time. The interaction between RhB molecules and photogenerated holes at the valence band of Ag3PO4 or Ag5I2PO4 is the cause of the cleavage of chromophore structure of RhB. The competition between these two pathways is strongly influenced by the ratio of AgI:Ag3PO4 in the prepared photocatalyst.113