Efficient visible light photocatalytic heterostructure of nonstoichiometric bismuth oxyiodide and iodine intercalated Bi2O2CO3

Bismuth oxide based (BOB) materials display strong potentials in visible light photocatalytic applications, but are greatly restricted by the poor stability for organic degradation in aqueous solutions. Herein, a unique heterostructural photocatalyst, nonstoichiometric bismuth oxyiodide Bi2O3-xI2x(x=0.243) covered with iodine intercalated Bi2O2CO3, were developed through a treatment of Bi7O9I3 in urea solution and subsequent calcinations. The interesting formation chemistry of this heterostructure were revealed and their dramatically enhanced photoresponse properties were studied. The lower amount of iodine in Bi2O3-xI2x contributes a higher oxidation potential of photogenerated holes, while the presence of outlayer of iodine intercalated Bi2O2CO3 retards the transformation of inner bismuth oxyiodide. We anticipate this strategy can be generalized to tune iodine contents and to fabricate delicate BOB photocatalytic heterostructures with desirable performance for environmental applications. (C) 2015 Elsevier B.V. All rights reserved.