Ultrasensitive Electrochemical Detection and Plasmon-Enhanced Photocatalytic Degradation of Rhodamine B Based on Dual-Functional, 3D, Hierarchical Ag/ZnO Nanoflowers

• Main Authors: Balram, D. (Author), Sebastian, N. (Author), Yu, W.-C (Author)
• Format: Article
• Language: English
• Published: MDPI 2022
• Subjects: Adverse side effects; Chemical detection; ELectrochemical detection; electrochemical sensor; Electrodes; High resolution transmission electron microscopy; II-VI semiconductors; Level detections; Light; Morphology; Nanocomposites; Nanomolar levels; Nanorods; Organic pollutants; photocatalysis; Photocatalysis; Photocatalytic degradation; Photodegradation; Rate constants; Reusability; Rhodamine-B; Rhodium compounds; Scanning electron microscopy; Screen-printed carbon electrodes; Sensitive detection; Silver nanoparticles; synthetic dye; Synthetic dyes; Ultrasensitive; voltammetry; zinc oxide; Zinc oxide
• Online Access: View Fulltext in Publisher

 The sensitive detection and degradation of synthetic dyes are pivotal to maintain safety owing to the adverse side effects they impart on living beings. In this work, we developed a sensitive electrochemical sensor for the nanomolar-level detection of rhodamine B (RhB) using a dual-functional, silver-decorated zinc oxide (Ag/ZnO) composite-modified, screen-printed carbon electrode. The plasmon-enhanced photocatalytic degradation of organic pollutant RhB was also performed using this nanocomposite prepared by embedding different weight percentages (1, 3, and 5 wt%) of Ag nanoparticles on the surface of a three-dimensional (3D), hierarchical ZnO nanostructure based on the photoreduction approach. The structure and morphology of an Ag/ZnO nanocomposite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental mapping, ultraviolet-visible (UV-vis) spectroscopy, and X-ray diffraction (XRD). The electrochemical sensor exhibited a very high sensitivity of 151.44 µAµM−1 cm−2 and low detection limit of 0.8 nM towards RhB detection. The selectivity, stability, repeatability, reproducibility, and practical feasibility were also analyzed to prove their reliability. Furthermore, the photocatalysis results revealed that 3 wt% of the Ag/ZnO hybrid nanostructure acquired immense photostability, reusability, and 90.5% degradation efficiency under visible light. Additionally, the pseudo-first-order rate constant of Ag-3/ZnO is 2.186 min−1 suggested promising activity in visible light photocatalysis. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.