Switching the type of redox activity of colloidal nanoceria by Re3+ (Re = Y, Eu, Tb) doping

[Display omitted] •Surface structure determines the type of redox activity of nanoceria.•Nanoceria decomposes hydrogen peroxide without generation of hydroxyl radicals.•Presence of Ce3+-Vo-Ce3+ surface complexes provides nanoceria by enzyme-like action.•Ce3+-Vo-Re3+ complexes (Re = Y, Eu) provide Fenton-like HP decomposition.•Kinetics of HP decomposition by nanoceria is similar to kinetics of enzyme action. Nanoceria (CeO2-x) is well-known for its enzyme-like antioxidant activity determined by Ce3+↔Ce4+ redox cycles on the surface of nanoparticle during interaction with reactive oxygen species. We show the crucial role of the surface defect structure in the mechanisms of interaction of Re3+ (Re = Y, Eu, Tb) - doped nanoceria with hydrogen peroxide (HP) and hydroxyl radicals (•OH). Both catalase-like (for CeO2:Tb3+) and Fenton-like (for CeO2:Y3+ and CeO2:Eu3+) HP decomposition was observed for Re3+-doped ceria nanoparticles leading to antioxidant or prooxidant activity, respectively. Overall, the type of Re3+ ion determines the mechanism and efficiency of redox activity of nanoceria.