Graphene Modified ZnO/Polyaniline Electrode Material for Electrochemical Sensing of Phenol Compounds

This study was aimed at developing an electrochemical sensor for the detection of phenol, a harmful organic pollutant for both humans and the environment. The sensor was developed by investigating metal oxide and conductive polymer modifiers on graphene electrodes to enhance the sensitivity for the phenol detection. In this research, the production of an electrode is discussed that is very sensitive to phenolic compounds using a composite of zinc oxide and polyaniline modified graphene (Gr/ZnO@PANi). The Gr/ZnO nanocomposite synthesis was carried out using a simple hydrothermal method and modification of PANi on the electrode surface by the electropolymerization method. It was found that the Gr/ZnO@PANi composite electrode can detect phenol effectively, with an efficient electron transfer occurring at a low oxidation potential. Additionally, it was observed that the electrode sensitivity to the phenol concentration was remarkably linear within a range of 10^–6–10^–1 M, and its limit of detection was as low as 0.0515 μM. Furthermore, the Gr/ZnO@PANi composite electrode exhibited excellent stability in detecting phenolic compounds, as indicated by the low stability coefficients of the relative standard deviation for reproducibility (0.37%) and the randomized strategic demand reduction (1.02%). Those findings suggest that the new Gr/ZnO@ PANi composite electrode is a promising tool for the sensitive detection of phenol in the environment, which could contribute to mitigating its negative impacts on human health and ecosystems. Future studies could explore the potential applications of this sensor for detecting other types of pollutants as well.