Fenton　and　Fenton-like　reactions　are　common　processes　that　usually　occur　during　the　oxidation　of　organic　substrates.　Unlike　the　Fe2+/H2O2　Fenton　system　of　which　the　catalytic　mechanisms　are　dominated　by　the　production　of　•OH,　that　of　FeIII　Fenton-like　system　are　to　date　still　confusing.　In　this　study,　the　activation　of　H2O2　was　investigated　by　employing　an　FeIII　based　layered　double　hydroxide　(MF-CO3)　as　the　catalyst　and　phenol　as　the　target.　It　reveals　that　the　catalytic　property　of　MF-CO3　is　much　superior　than　its　counterpart　of　MF-Na　synthesized　with　similar　procedure.　The　investigation　of　phase　structure　and　morphology　indicate　that　MF-CO3　possesses　higher　degree　of　crystallinity.　The　results　of　XPS,　IR　measurements　suggest　that　CO32–　content　in　MF-CO3　is　obviously　higher　than　that　in　MF-Na.　Furthermore,　the　tests　of　free　radicals　reveal　that　•OH　and　1O2　are　the　main　ROSs　generated　during　the　activation　process　with　HO2•/O2•-　non-detectable,　which　was　different　from　the　previously　reported　Fenton/Fenton-like　system　in　the　presence　of　HO2•/O2•-.　CO32–　assisted　hemolysis　of　H2O2　in　the　catalyst　is　proposed　herein　for　an　in-depth　understanding　of　the　interactions　between　surface　FeIII　and　H2O2.　It　is　suggested　that　the　oxidation　of　FeIII　intermediate　to　produce　·OH　is　possibly　one　of　the　essential　steps　of　activation.　It　is　firstly　reported　for　the　positive　impact　of　the　CO32–　on　the　activation　mechanism　of　FeIII　based　catalyst.　The　results　would　give　new　insights　for　comprehending　the　FeIII　Fenton-like　process　especially　with　the　existence　of　CO32–　which　is　a　major　inorganic　species　in　water　matrices.　©　2024