Ultrathin polypyrrole-derived porous carbon nanosheets integrated with FeO nanoparticles for enhanced electrochemical detection of catechin.

The development of two-dimensional porous carbon nanosheets (mNPC) presents a promising solution to address the aggregation challenges of transition metal oxides in catalytic sensing applications. In this study, hierarchical porous carbon nanosheets were synthesized through a dual-template strategy employing octadecylamine and the block copolymer PEO-b-PS during pyrrole monomer polymerization under mild conditions, followed by controlled pyrolysis. Subsequent uniform dispersion of FeO nanoparticles on the carbon matrix yielded an advanced mNPC/FeO nanocomposite. Comprehensive characterization via field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed the successful formation of the hierarchical porous structure and homogeneous distribution of FeO. Electrochemical evaluation revealed that the mNPC/FeO modified glassy carbon electrode exhibited exceptional electrocatalytic performance for catechin detection, achieving an ultra-low detection limit of 0.36 nM (S/N = 3) with a broad linear response range from 0.1 nM to 1.1 μM under optimized conditions. The sensor demonstrated remarkable anti-interference in complex matrices. This work not only provides a novel strategy for food safety monitoring but also expands the application scope of conductive polymer-derived nanomaterials in electrochemical sensing platforms.