Abstract
The catalytic activity of SrPdO3 perovskite, prepared by the sol-combustion citrate method, for the hydrazine oxidation has been investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The strong acidic condition is essential for the high catalyst performance, where five-protons mechanism is verified. The calculated value of the diffusion coefficient from kinetics data is 8.01x 10(-6) cm(2) s(-1). The proposed sensor exhibits a high sensitivity, 2.1x10(3) mu A mu mol(-1) L, excellent selectivity and reproducibility, high operating and storage stability. The calculated limit of detection (LOD) for hydrazine is 8.3 x 10(-2) nmol L-1. Impedance study showed that, in the presence of SrPdO3, the charge-transfer resistance (Re T ) is decreased by a factor of 100, compared to that of bare electrode, indicating the high catalytic activity of SrPdO3 for the hydrazine electro-oxidation. This can be attributed to the highly dispersed nano-palladium sites within the perovskite matrix. (C) 2018 The Electrochemical Society.