Dual modification of BiOIO3 via doping iodine and fabricating heterojunction with basic bismuth salt: Facile synthesis, superior performance for degradation of multiple refractory organics

An approach of simultaneous iodine doping and heterojunction fabricating with basic bismuth salt was proposed, Based on this, a novel I/BiOIO 3 /[Bi 6 O 6 (OH) 3 ](NO 3 ) 3 ∙1.5H 2 O (I/BiOIO 3 /BHN) photocatalyst was prepared. The photocatalytic activity was evaluated by the degradation of multiple refractory pollutants (rhodamine B, methyl orange, phenol , bisphenol A, bisphenol B, bisphenol Z) in water under solar light irradiation. Compared with single photocatalyst, the optimized sample displayed the reaction rate constant of 0.1606 min −1 , which was 69.8, 11.4 and 2.2 times of individual [Bi 6 O 6 (OH) 3 ](NO 3 ) 3 ∙1.5H 2 O, BiOI and BiOIO 3 , respectively. The performance improvement was attributed to the inhibition of charge carrier recombination by type II heterojunction formation and the expanded solar capture range caused by the springboard effect of iodine impurity level. The photocatalytic mechanism of I/BiOIO 3 /BHN was hole oxidation , followed by·OH oxidation. Besides, the I/BiOIO 3 /BHN photocatalyst in bulk structure with micrometer size and high-density could be easily separated and recovered by simple sedimentation, confirming its good application prospect in the wastewater treatment .