Theoretical Study on Cobalt Ferrite ConFe3−nO4 (n = 1–2) Nanoparticles with Multi-enzyme Activities

Abstract

Through on the basis of density functional theory calculations (DFT), harmonic transition state theory and d-band center theory, the reaction mechanism and catalytic activity of Catalase, Superoxide dismutase and Peroxidase activities on the ConFe3−nO4 (n = 1–2) are systematically investigated. The results show that CoFe2O4 is the most stable catalyst with the best catalytic effect. For the simulated activity of catalase, we find that the path-3 (H* and HO* → H2O) is the best on CoFe2O4 and Co2FeO4. For the simulated activity of superoxide dismutase, the path HOO* + HOO → H2O2 + O2 is optimal on CoFe2O4 and Co2FeO4. For the simulated activity of peroxidase, the mechanism on CoFe2O4 and Co2FeO4 is OOH* + H* → H2O + O*, O* + TMB → OH* + oxTMB, OH* + TMB → H2O + oxTMB. The results of these methods are consistent. The results thus provide an in-depth insight into the reaction mechanism and activity of ConFe3−nO4 as catalase, superoxide dismutase and peroxidase mimics and may play a role in the application of nanoparticles as mimics.