Bifunctional approach for electrochemical detection and catalytic degradation of Rhodamine B in environmental samples using a NiFe2O4@C/PPy catalyst: Kinetic and thermodynamic insights
M. Thomas, Sanjay Ballur Prasanna, Akash Ashokrao Jagtap, Gagankumar Sakleshpur Kumar, Yu-Chien Lin, Rajalakshmi Sakthivel, Ching‐Wei Tung, Ren‐Jei Chung
Abstract
Rhodamine B (RhB), a highly toxic dye commonly found in industrial effluents , is hazardous to both human health and aquatic life. To address this issue, we developed a NiFe 2 O 4 @C/polypyrrole (NFC/PPy) nanocomposite as a bifunctional catalyst for the sensitive detection and degradation of RhB in the presence of NaBH 4 . The catalyst was prepared using hydrothermal and in-situ oxidative polymerization methods. The prepared catalysts were characterized using various spectroscopic and analytical techniques. Several parameters, such as the initial dye concentration, adsorbent dosage, NaBH 4 concentration, and temperature, were evaluated during RhB degradation. Under optimal conditions, the NFC/PPy catalyst degraded 80 % of RhB (0.0186 min −1 ) in the sample within 100 min. Catalyst performance in dye-contaminated river and pond water samples was investigated, and the toxicity of the RhB solution before and after degradation was studied using mung bean germination. Furthermore, the NFC/PPy/GCE electrode was employed for RhB detection using cyclic voltammetry and differential pulse voltammetry . The fabricated sensor exhibits a good linear range of detection of 0.175–796.6 µM, a limit of detection of 1.13 nM, and a sensitivity of 0.304 µA µM −1 cm −2 . The constructed electrode exhibited excellent reproducibility, repeatability, and storage stability. Our study demonstrates the catalytic reduction and electrochemical properties of NFC/PPy, highlighting its potential as a bifunctional catalyst for RhB degradation.