0D/2D dual Fenton α-FeO/Fe-doped g-CN photocatalyst and the synergistic photo-Fenton catalytic mechanism insight.

A novel dual Photo-Fenton photocatalyst FeO-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-FeO quantum dots on ultrathin porous Fe-doped carbon nitride (Fe-CN) nanosheets. The iron species in Fe-CN and α-FeO QDs constitute a mutually reinforcing dual Photo-Fenton effect. The 4% FeO-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-FeO QDs and the ultrathin porous structure of Fe-CN is the primary reason for the outstanding catalytic performance exhibited by α-FeO/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-FeO/Fe-CN interface enables more photogenerated electrons to participate in the Fe/Fe conversion and HO activation. The trapping experiments demonstrate that OH and O are the primary active species in TC degradation. This work presents novel insights into the design of efficient heterogeneous Fenton catalysts for practical applications.