A Novel Non-Enzymatic Efficient H2O2 Sensor Utilizing δ-FeOOH and Prussian Blue Anchoring on Carbon Felt Electrode

In this study, an efficient H2O2 sensor was developed based on electrochemical Prussian blue (PB) synthesized from the acid suspension of δ-FeOOH and K3[Fe(CN)6] using cyclic voltammetry (CV) and anchored on carbon felt (CF), yielding an enhanced CF/PB-FeOOH electrode for sensing of H2O2 in pH-neutral solution. CF/PB-FeOOH electrode construction was proved by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD), and electrochemical properties were verified by impedance electrochemical and CV. The synergy of δ-FeOOH and PB coupled to CF increases electrocatalytic activity toward H2O2, with the sensor showing a linear range of 1.2 to 300 μM and a limit of detection of 0.36 μM. Notably, the CF/PB-FeOOH electrode exhibited excellent selectivity for H2O2 detection in the presence of dopamine (DA), uric acid (UA), and ascorbic acid (AA). The calculated H2O2 recovery rates varied between 93% and 101% in fetal bovine serum diluted in PBS. This work underscores the potential of CF/PB-FeOOH electrodes in progressing electrochemical sensing technologies for various biological and environmental applications.