Hierarchically ordered porous nitrogen doped carbon modified a glassy carbon electrode for voltammetry detection of quercetin

Porous structure, large surface area, and favorable electrical conductivity play crucial roles in enhancing electrochemical response for small molecule detection. Herein, hierarchically ordered porous nitrogen-doped carbon (HOPNC) was synthesized via one-step carbonization of the as-prepared precursor of hierarchically ordered porous ZIF-8. A glassy carbon electrode modified with the HOPNC was used as a sensor to detect quercetin (Qu) via cyclic voltammetry and differential pulse voltammetry measurements with an accumulation step. The 3D hierarchically ordered porous structure of the material was characterized by scanning electron microscope, high-resolution transmission electron microscope, nitrogen adsorption-desorption techniques. The orderly interconnected macro/meso/microporous can accelerate the mass transfer and offer a large surface area to adsorb more target molecules. Moreover, N doping introduced abundant defects into the carbon matrix, which will be used as adsorption sites and reaction sites to promote the affinity and activation of the sample toward Qu. As a result, the HOPNC/GCE exhibits enhanced electroanalytical performance: (a) Two linear response towards Qu at the range of 0.1–20 μM (R2 = 0.987, sensitivity of 4.56 μA/μM) and 20–120 μM (R2 = 0.991, sensitivity of 0.88 μA/μM); (b) detection limit of 0.03 μM (S/N = 3); (c) recoveries of 94.0 %–100 % in Ginkgo biloba extract tablet.