Supramolecular photocatalyst of perylene bisimide decorated with α-Fe2O3: Efficient photo-Fenton degradation of organic pollutants

The composite of α-Fe2O3/PTCDI based on supramolecular photocatalyst of perylene bisimide (PTCDI) decorated with α-Fe2O3 was prepared via calcination of ferric nitrate with self-assembly PTCDI. The composite displayed an enhanced performance for the degradation of phenol pollutants and coking wastewater via photo-Fenton reaction relative to the single component, which owing to efficient charge transfer on the heterojunction and effective Fe3+/Fe2+ conversion. The degradation ratio of phenol by the composite catalyst was increased by 73 % and 17 % under photo-Fenton reaction compared with the constituent monomer of α-Fe2O3 and PTCDI respectively. For coking wastewater, the COD and TOC removal rates of α-Fe2O3/PTCDI were up to 66.7 % and 44.5 %. The enhanced degradation activity with photo-Fenton condition was attributed to the formed type II heterojunction between the two semiconductors, effectively inhibiting the recombination of e- and h+ and the injected electrons from PTCDI to α-Fe2O3 beneficial to the Fe3+/Fe2+ cycle, further promoting the Fenton reaction. This effective photo-Fenton degradation system shows potential application value in treatment of complex industrial wastewater.