A novel α-Fe2O3@g-C3N4 catalyst: Synthesis derived from Fe-based MOF and its superior photo-Fenton performance

Fabricating heterojunction catalysts is a promising strategy for improving the performance in heterogeneous photo-Fenton reaction (PFR). Herein, a Z-scheme heterostructured alpha-Fe2O3@g-C3N4 catalyst was successfully synthesized through the co-calcination of melamine and Fe-based MOF. The characterization results demonstrated that alpha-Fe2O3 nanoparticles anchored on the surface of g-C3N4 successfully. The degradation of tetracycline (TC) in visible-light/H2O2 system was adopted to evaluate the photo-Fenton activity of the catalysts. About 92% of TC was degraded by the optimum composite FOCN-0.45 in 60 min; the degradation rate (0.042 min(-1)) of TC by the FOCN-0.45 is 6, 7 and 14 times higher than that by pristine MIL-53 (Fe) (0.007 min(-1)), alpha-Fe2O3 (0.006 min(-1)) and g-C3N4 (0.003 min(-1)), respectively. The prepared FOCN-0.45 composite exhibited excellent performance and high stability in a wide range of pH value. The promoted photo-Fenton catalytic efficiency benefited from the Z-scheme heterojunctions of alpha-Fe2O3@g-C3N4, which enhanced the separation ability of photo-generated charge carriers and increased the electrons that participated in Fe2+/Fe3+ cycle. The boosting (OH)-O-center dot radicals degraded organic pollutants as main reactive radicals. This work presents a feasible path to design and synthesize heterogeneous photo-Fenton catalysts for the removal of organic pollutants.