In situ grown NiCo-LDH derived bimetallic nanoparticles on n-doped carbon nanorods for sensitive electrochemical sensing of chlorogenic acid

A highly sensitive electrochemical sensor for chlorogenic acid (CGA) detection has been developed using nitrogen-doped carbon nanorods loaded with NiCo bimetallic (NCNRs/NiCo). The composite material was synthesized through a pyrolysis strategy where NiCo-layered double hydroxide (LDH) was grown in situ on phenolic resin-derived carbon nanorods and subsequently carbonized. Material characterization confirmed the successful formation of uniformly dispersed NiCo nanoparticles anchored on nitrogen-doped carbon matrix, which provided abundant active sites. The NCNRs/NiCo-modified glassy carbon electrode (GCE) exhibited exceptional electrocatalytic activity toward CGA oxidation, achieving a wide linear detection range from 0.5 nM to 10 µM with an ultralow detection limit of 0.32 nM (S/ N  = 3). The sensor demonstrated excellent selectivity against common interferents, good reproducibility and repeatability. Practical application in food samples showed satisfactory recoveries (97.6-104.1%) in good agreement with the ultraviolet-visible (UV-Vis) reference method. The outstanding performance originates from the synergistic effects between nitrogen-doped carbon framework and bimetallic nanoparticles, offering a promising platform for natural antioxidant determination in food quality control. Graphical