The α-Fe2O3/g-C3N4 composite as an efficient heterogeneous catalyst with combined Fenton and photocatalytic effects

Integration of Fenton and photocatalytic processes in one reaction system may increase the degradation efficiency in wastewater treatments. In this work alpha- Fe2O3/g-C3N4 composites with different mass percentages of alpha-Fe2O3 have been prepared in order to catalyze the Fenton and photocatalytic reactions simultaneously. The catalytic efficiency is greatly boosted in the presence of H2O2 under visible-light irradiation compared with single Fenton or photocatalytic reactions. The composite with 0.38% alpha-Fe2O3 shows the best catalytic efficiency with a reaction rate constant of 0.10 min(-1) in the degradation of rhodamine B, which is about 8.4 and 3.7 times higher than that of pure alpha-Fe2O3 and pure g-C3N4 under the same conditions, respectively. This enhancement of the composites should be ascribed to a synergetic effect between alpha-Fe2O3 and g-C3N4. Moreover, a reasonable catalytic mechanism for the alpha-Fe2O3/g-C3N4 composite has been proposed.