Affiliation:
1. Malaysia-Japan International Institute of Technology (MJIIT) Universiti Teknologi Malaysia Kuala Lumpur Malaysia
2. Department of Biological and Chemical Engineering Aarhus University Aabogade 40 8200 Aarhus Denmark
3. School of Medicine Technical University of Munich Munich Germany
Abstract
AbstractThe present study details a more environmentally friendly method for synthesizing iron oxide nanoparticles (Fe3O4‐NPs) utilizing Hibiscus sabdariffa (H. sabdariffa) leaf extract. The produced H. sabdariffa/Fe3O4‐NPs underwent characterization through VSM, XRD, FESEM‐EDX, TEM and FTIR analyses. The FESEM and TEM images revealed that the H. sabdariffa/Fe3O4‐NPs had a narrow distribution and an average particle size of 5±2 nm. Catalytic degradation studies of the synthesized Fe3O4‐NPs exhibited efficient reduction of methyl orange (MO) dye. The degradation of MO catalysed by H. sabdariffa/Fe3O4‐NPs follow the pseudo‐first order kinetics, with a rate constant of 0.0328 s−1 (R2=0.9866). Moreover, in electrochemical sensing studies, the anodic peak current of nitrite (NO2−) for H. sabdariffa/Fe3O4‐NPs/GCE showed a linear relationship with its concentration within the range of 0.5–7.5 mM, achieving a detection limit of 0.29 μM. These findings demonstrate that the modified electrode with Fe3O4‐NPs synthesized using H. sabdariffa leaf extract serve as a novel electrochemical sensor for determining NO2− with high sensitivity and reproducibility.