Simultaneous Determination of 1-Naphthol and 2-Naphthol in Waters by Electrochemical Sensor Based on Magnetite Porous Reduced Graphene Oxide/Carbon Nanotube Hybrid

Abstract

The waste aqueous solutions containing naphthol are treated by physical and chemical methods. However, naphthols are toxic to environment and human health. So it is very important to simultaneously detect them, will make contributions to both the manufacture and the environment management. Herein we developed a simple, cost effective, electrochemical sensor based on magnetite (Fe₃O₄ nanoparticles) porous reduced graphene oxide/carbon nanotubes (Fe₃O₄@prGO-CNT) nanocomposite for simultaneous detection of 1-naphthol and 2-naphthol. Voltammetric responses suggest dramatical improvement of electrocatalytic properties of naphthols by incorporating Fe₃O₄@prGO-CNT on carbon paste electrode (CPE). Differential pulse voltammetric (DPV) measurement depicts large potential separation of about 200 mV between naphthols, allows their simultaneous determination from binary mixture. Under optimized condition, Fe₃O₄@prGO-CNT/CPE manifested linear relationships of 1-naphthol and 2-naphthol in the range of 0.5–30 and 0.7–40 μM with detection limit (S/N = 3) of 76 and 82 nM respectively. Moreover, Fe₃O₄@prGO-CNT/CPE showed satisfactory response towards wastewaters and river waters for determining 1-naphthol and 2-naphthol concentrations.