0D/2D dual Fenton α-Fe2O3/Fe-doped g-C3N4 photocatalyst and the synergistic photo-Fenton catalytic mechanism insight

A novel dual Photo-Fenton photocatalyst Fe2O3–Fe–CN with excellent Fe(III)/Fe(II) conversion efficiency and trace metal ion leaching rate has been fabricated by in-situ deposition of α-Fe2O3 quantum dots on ultrathin porous Fe-doped carbon nitride (Fe–CN) nanosheets. The iron species in Fe–CN and α-Fe2O3 QDs constitute a mutually reinforcing dual Photo-Fenton effect. The 4% Fe2O3–Fe–CN showed superior performance with kobs values 8.60 and 4.80 folders greater than pure CN and Fe–CN, respectively. The synergistic effect between α-Fe2O3 QDs and the ultrathin porous structure of Fe–CN is the primary reason for the outstanding catalytic performance exhibited by α-Fe2O3/Fe–CN. On one hand, the ultrathin porous structure of Fe–CN promotes the rapid transfer of photogenerated electrons. On the other hand, the efficient photogenerated charge separation at the α-Fe2O3/Fe–CN interface enables more photogenerated electrons to participate in the Fe3+/Fe2+ conversion and H2O2 activation. The trapping experiments demonstrate that •OH and •O2− are the primary active species in TC degradation. This work presents novel insights into the design of efficient heterogeneous Fenton catalysts for practical applications. © 2024