3D nitrogen-doped porous graphene aerogel as high-performance electrocatalyst for determination of gallic acid

In this work, three-dimensional nitrogen-doped porous graphene aerogel (NPGA) was easily synthesized via one-step hydrothermal reduction by mixing graphene oxide (GO) with p-phenylenediamine (PPD) and ammonia solution and then followed by freeze-dried. The NPGA sample was studied by different techniques such as SEM, TEM, nitrogen adsorption-desorption isotherms, XRD, XPS, and electrochemical measurements. NPGA composite exhibits a microporous with 3D structure, a large specific surface area and exposes edge plane like-sites/defects which lead to high electrical conductivity and facilitate electrons transfer towards the probe. The appropriate experimental conditions such as supporting electrolyte, pH value and scan rate were optimized before applying NPGA electrode to determine gallic acid (GAL) using differential pulse voltammetry (DPV) method. NPGA electrode shows superior electrochemical performance compared to the previous studies with regard to the limit of detection (0.067 μmol/L) and linear range (2.5–1000 μmol/L). The NPGA electrode provides a new way for GAL concentration determination with high selectivity, excellent stability, and good reproducibility. In addition, it is highly suitable for the detection of GAL concentration in real samples with excellent reliability.