Bismuth oxyiodide heterojunctions in photocatalytic degradation of phenolic molecules

作者：Han Aijuan; Chian Siew Fung; Toy Xiu Yi; Sun Jiulong; Jaenicke Stephan; Chuah Gaik Khuan^*

来源：Research on Chemical Intermediates, 2015, 41(12): 9509-9520.

DOI：10.1007/s11164-015-1976-7

• Bismuth oxyiodides
• Composites
• Heterojunction
• Photocatalysts
• Phenolic

Bismuth oxyiodide composites were synthesized and tested as photocatalysts under visible light irradiation. Calcination of bismuth oxyiodide, BiOI, at 420 A degrees C for various lengths of time led to composites with varying compositions of Bi7O9I3 and alpha-Bi5O7I. The ease of forming iodide-poor bismuth oxyhalides can be attributed to ready loss of the strongly reducing iodide ion. Thermogravimetric measurements show that BiOI is not thermally stable above 350 A degrees C. The Bi7O9I3/alpha-Bi5O7I composites formed active visible-light photocatalysts for the degradation of phenol, p-chlorophenol, p-cresol, and 4-tert-butylphenol. Compared to BiOI, the rate constant for the photodegradation of phenol was 5-6 times higher over the Bi7O9I3/alpha-Bi5O7I composites. The excellent activity can be attributed to the efficient separation of photogenerated charge carriers at the intimately contacted heterojunctions of the in situ-generated composites.

• 出版日期2015-12