Pd nanoparticle-modified electrodes for nonenzymatic hydrogen peroxide detection

A hydrogen peroxide (H₂O₂) sensor based on Pd nanoparticles (NPs) and glassy carbon electrodes (GCEs) is fabricated. Pd NPs are deposited on GCEs by using a gas phase cluster beam deposition technique. The NP-deposited electrodes show enhanced electrocatalytic activity in reduction of H₂O₂. The electrode with an optimized NP coverage of 85 % has a high selective and stable nonenzymatic sensing ability of H₂O₂ with a low detection limit (3.4 × 10⁻⁷ M), high sensitivity (50.9 μA mM⁻¹), and a wide linear range (from 1.0 × 10⁻⁶ to 6.0 × 10⁻³ M). The reduction peak potential of the electrode is close to −0.12 V, which enables high selective amperometric detection of H₂O₂ at a low applied potential.