Engineering of core-shell Au nanorods@ZIF-8 electrocatalyst for sensitive voltammetric determination of 2-chlorophenol in aquaculture

Herein, polyvinylpyrrolidone-stabilized Au nanorods were controllably implanted into ZIF-8 to form a well-uniformed AuNRs@ZIF-8 electrocatalyst with a multicore-shell structure. After characterizing the chemical and physical properties, a novel electrochemical sensing platform was fabricated for 2-chlorophenol (2-CP) monitoring based on the AuNRs@ZIF-8 modified glassy carbon electrode. Due to the unique electrochemical property of AuNRs cores and ultra-porous architecture of ZIF-8 shell, the electrocatalyst would effectively accelerate the electron transfer and greatly improve the electrochemical response of 2-CP. Under the optimized experimental conditions, the oxidation peak current of 2-CP enhanced linearly with the increase of its concentration between 0.010 and 40 μM, and the limit of detection was 3.6 nM based on S/N = 3. Meanwhile, the prepared AuNRs@ZIF-8 electrode showed favorable stability, reproducibility, and selectivity, which could be applied to the accurate analysis of 2-CP in aquaculture with standard addition recovery ranging from 96.67% to 104.0%.