Electroactive NiHCF/PANI hybrid films prepared by pulse potentiostatic method and its performance for H2O2 detection

Organic–inorganic hybrid films composed of nickel hexacyanoferrate/polyaniline (NiHCF/PANI) were successfully fabricated on a carbon nanotubes (CNTs) modified Pt substrate using pulse potentiostatic method (PPM). Morphologies and structures of the as-prepared hybrid films were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and energy dispersive X-ray spectroscopy (EDS). The amounts and structures of PANI and NiHCF were respectively tuned by adjusting the operation conditions in PPM, and the films with homogeneous cubic NiHCF/PANI hybrid nano-particles exhibit high electrocatalytic property and “insoluble” form of NiHCF were achieved. Due to the electrochemical oxidation effect of pulse potential, new functional groups such as hydroxyl, hydrogen sulfuric acid ester were introduced onto CNTs, which resulted in an acidic micro-environment for PANI to maintain its electroactivity in neutral aqueous solutions. Such hybrid films were applied for hydrogen peroxide (H2O2) detection, and a linear dependence on H2O2 concentration in the range of 1.25 × 10−6 to 2.95 × 10−3 M (r = 0.998) with a high sensitivity of 3119 mA M−1 cm−2 were obtained.