Sensitive and selective electrochemical sensor for detecting 4-nitrophenole using novel gold nanoparticles/reduced graphene oxide/activated carbon nanocomposite

Abstract

4-Nitrophenole (4-NP) is a key hazardous pollutant that has a direct impact on humans and environment, and hence the development of efficient electrochemical sensors for the detection and monitoring with good sensitivity and selectivity is highly desirable. Herein, we report an efficient electrochemical detection of 4-NP based on AuNPs/rGO combined with biomass-derived activated carbon (AC) synthesized from the local date seeds. Such newly developed AuNPs/rGO/AC modified glassy carbon electrode (GCE) provided rich active centers with efficient electrochemical reductive activity that led to promote the adsorption and diffusion of 4-NP molecules onto the active surface electrode, enabling better electrochemical detection of the target analyte. With the amperometric technique, the current modified electrode is capable to detect the 4-NP with a low limit of detection (LOD) of 0.36 µM at (S/N=3), a high sensitivity of 0.03436 μAµM−1 in a wide linear dynamic range (LDR) of 18-592 µM, and a rapid response time <10 s. The present AuNPs/rGO/AC modified GCE exhibited excellent selectivity in the presence of various common interfering chemicals, good repeatability and reproducibility and sufficient storage stability. The current sensor electrode also exhibited satisfactory analytical recovery results of 4-NP from spiked real samples. The current developed AuNPs/rGO/AC nanocomposite can represent a promising active electrode material for efficient detection of various environmental pollutants by the electrochemical approach.