Electrochemical determination of ascorbic acid at Ag2S - CuO - ZnO ternary nanocomposite modified glassy carbon electrode

Abstract

In this work, a novel ternary nanocomposite electrochemical sensor based on Ag₂S-CuO-ZnO was developed and put to use for ascorbic acid (AA) electrochemical detection. By combining CuO-ZnO and AgNO₃ precursors, an easy-to-use and inexpensive homogeneous precipitation procedure was used to produce the Ag₂S-CuO-ZnO nanocomposite. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), and ultraviolet-visible (UV–VIS) spectroscopy were used to analyze the produced ternary nanocomposite. AA displayed an irreversible oxidation peak on the cyclic voltammograms (CVs) at Ag₂S-CuO-ZnO nanocomposite modified glassy carbon electrode (Ag₂S-CuO-ZnO/GCE). The enhanced sensitivity of AA detection at Ag₂S-CuO-ZnO/GCE was attributed to the ternary nanocomposite's synergistic effects and improved electron transfer efficiency. Using linear sweep voltammetry (LSV), the proposed electrochemical sensor demonstrated a linear range of 1 - 150 μM with a limit of detection (LOD) of 0.73 μM. The demonstrated sensor's practical applicability was successfully used to determine the amount of AA in an orange sample.