Carbon black as low-cost alternative for electrochemical sensing of phenolic compounds

Due to the toxicity and widespread presence of phenolic compounds in the environment, their accurate detection and monitoring is of great importance. The aim of this work was to find a viable low-cost alternative to expensive carbon nanomaterials such as carbon nanotubes and graphene. Carbon black, a conductive carbon nanomaterial that is produced in bulk quantities and is therefore cheap and readily available, was dropcoated onto glassy carbon electrode and used as electrochemical sensor to detect three phenolic compounds, catechol, p-cresol and p-nitrophenol. Compared to bare glassy carbon, the carbon black-modified electrode exhibited greatly enhanced current densities and lower oxidation potentials for all three phenols. Calibration curves of catechol and p-cresol showed good linear response with concentration in the micromolar range, and detection limits of 41 and 63 nM were found for catechol and p-cresol, respectively. These results demonstrate the potential of carbon black as a low-cost, high-performance material for electrochemical sensing applications.