A nonenzymatic electrochemical H₂O₂ sensor based on macroporous carbon/polymer foam/PtNPs electrode

Herein, a nonenzymatic electrochemical H₂O₂ sensor was developed based on Pt nanoparticles (PtNPs)/Schiff base foam (SBF)/three-dimensional macroporous kenaf stem-derived carbon (TMKSDC). The SBF composed of thin SB layers with single atomic thickness was firstly grown on TMKSDC as a supporting matrix via hydrazine anhydrous–terephthalaldehyde amino-aldehyde condensation reaction. Subsequently, lots of electroactive nanosized PtNPs were electrodeposited on SBF/TMKSDC to form PtNPs/SBF/TMKSDC integrated electrode. The surface morphology and pore feature of PtNPs/SBF/TMKSDC integrated electrode were explored by scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, atomic force microscope and N₂ adsorption/desorption isotherms. Cyclic voltammetry and chronopotentiogram methods were used to study the electrochemical properties of PtNPs/SBF/TMKSDC integrated electrode for H₂O₂ sensing. Results showed that the nonenzymatic electrochemical H₂O₂ sensor based on PtNPs/SBF/TMKSDC integrated electrode had a good performance. The detection limit was about 0.022 μM, and the linear range was 0.065 μM–0.45 mM with a sensitivity of 760 μA mM⁻¹ cm⁻² and 0.45–1.775 mM with a sensitivity of 610 μA mM⁻¹ cm⁻². The good performances originated from the hierarchically porous structures, the large specific surface of PtNPs/SBF/TMKSDC and the super catalytic activity and distribution of nanosized PtNPs. It was noteworthy that the PtNPs/SBF/TMKSDC integrated electrode might also be applied in other fields.