La0. 6Sr0.4FeO3-? and La0.6Sr0.4Co0.2Fe0. 8O3-? Perovskite Materials for H2O2 and Glucose Electrochemical Sensors

LaxSr1-xCoyFe1-yO3-d perovskites were investigated as electro-catalytic materials for H2O2 and glucose electrochemical sensors. La0.6Sr0.4FeO3-d and La0.6Sr0.4Co0.2Fe0.8O3-d formulations have been synthesized by citrate method and characterized by XRD and SEM. TPR and XPS analyses were performed to evaluate the oxidation states of metal ions and surface composition. The electrochemical performances of H2O2 and glucose sensors fabricated by modifying commercial screen printed carbon electrodes with perovskites, were evaluated by cyclic voltammetry and amperometry in alkaline medium. Results demonstrated that the substitution of Fe with Co ions in the ferrite structure enhance the electrocatalytical activity towards the oxidation of H2O2 and glucose.