Removing lignin model pollutants with BiFeO 3 -g-C 3 N 4 compound as an efficient visible-light-heterogeneous Fenton-like catalyst.

BiFeO ₃ -g-C ₃ N ₄ nanoscaled composite was prepared with a hydrothermal method and evaluated as a highly efficient photo-Fenton like catalyst under visible light irradiation. The BiFeO ₃ -g-C ₃ N ₄ composite exhibited much stronger adsorption ability to lignin model pollutant (guaiacol) than that of BiFeO ₃ , which may be due to the higher specific surface area (BiFeO ₃ -g-C ₃ N ₄ : 35.59m ² /g>BiFeO ₃ : 7.42m ² /g) and the adsorption form of π-π stack between g-C ₃ N ₄ and guaiacol. The composite exhibited excellent visible light-Fenton like catalysis activity, being influenced by the solution pH value and the proportions of BiFeO ₃ and g-C ₃ N ₄ nanosheets. Under optimal conditions with visible light irradiation, the BiFeO ₃ -g-C ₃ N ₄ composite yielded fast degradation of guaiacol with an apparent rate constant of 0.0452min ^-1 , which were 5.21 and 6.80 folds of that achieved by using BiFeO ₃ and the mixture of BiFeO ₃ and g-C ₃ N ₄ nanosheets, respectively. The significantly enhanced visible light-Fenton like catalytic properties of the BiFeO ₃ -g-C ₃ N ₄ composite in comparison with that of BiFeO ₃ was attributed to a large surface area, much increased adsorption capacity and the semiconductor coupling effect between BiFeO ₃ and g-C ₃ N ₄ in the composite.
(Copyright © 2016. Published by Elsevier B.V.)