Fabrication of a nichrome electrode coated with silver microcrystals, and its application to sensing hydrogen peroxide

Abstract

In this paper, a new kind of electrode for sensing hydrogen peroxide (H₂O₂) was reported. Silver microcrystals were initially deposited on a nichrome substrate by cyclic voltammetry and controlled potential electrolysis, respectively. Scanning electron microscopy was applied to characterize the morphology of the silver microparticles on the nichrome surface. The micron-silver nichrome electrode exhibits a sensitive electrochemical response to H₂O₂ in pH 4.5 buffer solution, and its catalytic activity is much higher than that of a pure silver electrode. Under the optimum conditions, the well-defined reduction peak current increases linearly with H₂O₂ concentration in the range of 9.8 × 10⁻⁵∼5.9 × 10⁻³ M, and the detection limit is 0.58 μM. The electrode can be applied to the voltammetric determination of H₂O₂, and recoveries of artificial samples are between 99.7%–107.0%.