Oxygen vacancy modulated interface chemistry: identifying iron( iv ) in heterogeneous Fenton reaction

WO 3−x switched the reaction of Fe II with H 2 O 2 from the formation of Fe III towards the direct generation of Fe IV . Fe IV was reduced to Fe III /Fe II by electrons localized in the t 2g orbitals of WO 3−x , which favored the generation of ˙O 2 − , ˙OH, and 1 O 2 .