Novel photoelectrochemical hydrogen peroxide sensor based on hemin sensitized nanoporous NiO based photocathode

•A novel photocathode based on hemin sensitized nanoporous NiO (3D) was developed.•The photocathode exhibited enhanced cathodic photocurrent under visible light.•The cathodic photocurrent showed a sensitive and selective response toward H2O2.•The PEC sensor was also successfully applied to detect H2O2 in real samples.

In this paper, a novel, facile and self-operating photocathode based on hemin sensitized three-dimensional (3D) nanoporous NiO was developed. Compared with pure NiO nanomaterials, the as prepared hemin sensitized NiO photocathode showed enhanced cathodic photocurrent under visible-light irradiation (λ ≥ 400 nm). The cathodic photocurrent was sensitively and selectively enhanced upon the addition of H2O2. The common interferents such as ascorbic acid, dopamine, and glutathione, caused less than 10% of the photocurrent change compared with the photocurrent response of the same concentration (2.0 × 10− 5 mol/L) of H2O2 on ITO/NiO/hemin electrode, indicating good selectivity of the method. The ITO/NiO/hemin electrode showed a linear range of 0.5–500 μmol/L with a low detection limit of 0.1 μmol/L (S/N = 3) for the detection of H2O2. In addition, the method was also successfully applied to the detection of H2O2 in real samples.

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