Electrochemical preparation of poly (direct yellow 11) modified pencil graphite electrode sensor for catechol and hydroquinone in presence of resorcinol: A voltammetric study

Present study describes the fabrication of new electrochemical sensor by electropolymerization of direct yellow 11 on the surface of pencil graphite electrode (PGE) for the investigation of catechol (CC) and hydroquinone (HQ) in the presence of resorcinol (RS). The modified electrode surface was further characterized by Transmission electron microscopy (TEM) and Field Emission Scanning Electron Microscope (FESEM). After the modification of PGE, it exhibits an excellent electrochemical response for the analytes using cyclic voltammetry (CV) and differential pulse voltammetric (DPV) technique. Specific parameters including varying concentration of analytes, sweep rate and pH solution were optimized to the electrode. The kinetic property of a modified electrode was got to be both adsorption and diffusion controlled and it give lower detection limit for CC (0.11 mu M) and HQ (0.16 mu M) respectively. In the simultaneous electroanalysis, bare PGE was failed to depict the oxidation peaks, whereas modified electrode gives well separated three anodic peaks for CC, HQ and RS with superior enhancement in peak current. The proposed modified electrode was applied for the quantification of CC, HQ and RS in a tap water and obtained a consistent recovery in-between 96 and 100 %. The proposed sensor can be fabricated using a simple method with a low cost.