Simultaneous electrochemical determination of benzenediol compounds in environmental samples using nano architectures of hydrogen ammonium zinc molybdate layered double hydroxides integrated with carbon black modified electrode

Abstract

Phenolic compounds, such as benzenediol (BD), are toxic and exhibit poor biodegradability, posing a threat to human health and the environment, even at low concentrations. Therefore, the simultaneous detection of BD at low detection limits and a wide detection range is of significant interest for monitoring water quality and environmental remediation efforts. In this study, we developed a novel electrochemical sensor for BD based on a nanocomposite (NC) of hydrogen ammonium zinc molybdate layered double hydroxide (AZnMo-LDHs) and carbon black (CB) as a modification for the electrode. Various characterization methods were employed to verify the morphological, structural, and physical-chemical properties of AZnMo-LDHs/CB NC. The NC-modified electrode exhibited low electrical resistance, high electrocatalytic activity, and fast electron transport, thanks to the synergistic effects between AZnMo-LDHs and CB. Additionally, the NC-modified electrode demonstrated excellent electrochemical performance in selectively and simultaneously detecting hydroquinone (HQ), catechol (CC), and resorcinol (RC). Differential pulse voltammetric studies confirmed that AZnMo-LDHs/CB NC enabled the detection of HQ, CC, and RC within linear response ranges of 0.05–971 μM, 0.1–1036 μM, and 0.5–1408.5 μM, respectively, with detection limits of 0.0054 μM, 0.0018 μM, and 0.075 μM. To validate the sensor's practical application, we tested it with multiple environmental samples, including water and soil, and obtained excellent recovery rates for HQ, CC, and RC.