Design of a Co-Doped Carbon Backbone with Self-Grown AU Nanoparticles Via a ‘Triple Advantage’ Strategy for Sensitive Dopamine Detection

Abstract

In this study, a Co-doped polyhedral carbon skeleton (Co CN) was prepared by nitrogen carbonization using ZIF-67 as a precursor. The Co CN features a rough surface with excellent electrical conductivity, and the Co atoms exhibit unique catalytic properties. Based on these characteristics, we used Co CN as a carrier to load Au nanoparticles (NPs) onto its surface through the linkage and reduction effects of polyoxometalates (POMs). The resulting Au/POM/Co CN three-component composite nanoparticles demonstrated outstanding performance in dopamine detection, with a good linear response in the range of 0.4–298 μM and a limit of detection (LOD) as low as 0.198 μM. Additionally, the sensor showed excellent stability, anti-interference properties, and high recovery in experimental tests. This approach provides a novel concept for bimetallic catalysis and expands possibilities for dopamine detection.

Keywords: Dopamine, Co-doped polyhedral carbon skeleton, Polyoxometalates, Gold nanoparticles, Electrochemical sensor