Electrochemical Sensing Platform Based on Lotus Stem‐derived Porous Carbon for the Simultaneous Determination of Hydroquinone, Catechol and Nitrite.

A simple and highly selective electrochemical sensor based on carbonized lotus stem (CLS) was developed for the simultaneous determination of hydroquinone (HQ), catechol (CC), and nitrite (NT) by using cyclic voltammetry (CV) and amperometry (AMP) methods. The CLS was characterized by the methods including field emission scanning electron microscopy (FE‐SEM), Raman spectrum, FT‐IR spectrum and X‐ray diffraction (XRD). Brunauer‐Emmett‐Teller (BET) method was used to evaluate the pore structure and surface area of CLS. The oxidation peaks for HQ (116.2 mV), CC (220.1 mV), and NT (818.9 mV) were well separated under optimized conditions, which improved their simultaneous determination. The CLS modified electrode showed a good linear range between 1.0×10 −6 to 7.0×10 −4 M for HQ, and the detection limit was calculated as 0.15 μM. For CC the linear relationship was 1.0×10 −6 to 3.0×10 −3 M with the detection limit of 0.11 μM. For NT the linear relationship was 5.0×10 −7 to 4.0×10 −3 M with the detection limit of 0.09 μM. The results indicated that the intrinsic structure of natural biomass can be expected to design porous carbon for electrochemical sensors. [ABSTRACT FROM AUTHOR]